Biology EOC Practice-randomized & Timed
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A strand of DNA is made up of the bases CATAGCGTA. What is the complementary base sequence on the other strand of DNA?
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CATAGCGTA
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UTATCUCAT
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GTATCGCAT
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CAUAGCCUA
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38 questions; 45 minutes. This test randomly selects questions from quizzes that we have taken in class.
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- 2.
Which of the following structures serves as the cell’s boundary from its environment?
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Mitochondrion
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Cell Membrane
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Chloroplast
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Channel Proteins
Correct Answer
A. Cell MembraneExplanation
The cell membrane serves as the cell's boundary from its environment. It is a selectively permeable barrier that controls the movement of substances in and out of the cell. It allows essential molecules to enter the cell while keeping harmful substances out. The cell membrane also plays a role in maintaining the cell's shape and providing support. Mitochondria are responsible for energy production, chloroplasts are involved in photosynthesis, and channel proteins assist in the transport of specific molecules across the cell membrane.Rate this question:
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- 3.
The first trophic level of any ecosystem is occupied by organisms such as
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Lions, wolves, and snakes.
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Humans, bears, and pigs.
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Cows, horses, and caterpillars.
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Plants, bacteria, and algae.
Correct Answer
A. Plants, bacteria, and algae.Explanation
The first trophic level of any ecosystem is occupied by organisms that are capable of producing their own food through photosynthesis or chemosynthesis. Lions, wolves, snakes, humans, bears, pigs, cows, horses, and caterpillars are all consumers that rely on other organisms for food and therefore do not belong to the first trophic level. Plants, bacteria, and algae, on the other hand, are primary producers that convert energy from the sun or chemicals into organic matter, making them the correct answer for the first trophic level.Rate this question:
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- 4.
What characteristic of early autotrophs gave them an advantage over early heterotrophs?
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They ate heterotrophs.
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They produced spores.
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They made their own food.
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They reproduced asexually.
Correct Answer
A. They made their own food.Explanation
Early autotrophs had an advantage over early heterotrophs because they were able to produce their own food. Autotrophs are organisms that can synthesize organic compounds from inorganic substances, such as sunlight and carbon dioxide, through processes like photosynthesis. This ability allowed them to obtain energy directly from their environment, whereas heterotrophs had to rely on consuming other organisms for their energy needs. By being able to produce their own food, autotrophs had a more reliable and independent source of energy, giving them a competitive edge over heterotrophs.Rate this question:
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- 5.
The X and Y chromosomes are called the
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Extra chromosomes.
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Phenotypes.
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Sex chromosomes.
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Autosomes.
Correct Answer
A. Sex chromosomes.Explanation
The X and Y chromosomes are called sex chromosomes because they determine the sex of an individual. In humans, females have two X chromosomes (XX) and males have one X and one Y chromosome (XY). These chromosomes carry genes that are responsible for the development of sexual characteristics and reproductive functions. The term "sex chromosomes" is used to differentiate them from autosomes, which are non-sex chromosomes that carry genes for other traits.Rate this question:
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- 6.
A pigment is a light-absorbing molecule.
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True
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False
Correct Answer
A. TrueExplanation
A pigment is a substance that absorbs certain wavelengths of light and reflects others, resulting in the perception of color. This process occurs because pigments contain molecules that can absorb specific wavelengths of light, preventing them from passing through or being reflected. Therefore, it is correct to say that a pigment is a light-absorbing molecule.Rate this question:
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- 7.
The energy of the electrons passing along the electron transport chain is used to make
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Citric acid
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Alcohol
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Lactic acid
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ATP
Correct Answer
A. ATPExplanation
The energy of the electrons passing along the electron transport chain is used to make ATP. ATP (adenosine triphosphate) is a molecule that stores and releases energy for cellular processes. During cellular respiration, electrons from molecules like glucose are transferred along the electron transport chain, which generates a proton gradient. This gradient is used by ATP synthase to produce ATP from ADP and inorganic phosphate. Therefore, the correct answer is ATP.Rate this question:
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- 8.
A trisomy of chromosome 21 causes what condition?
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Albinism
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Dwarfism
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Down syndrome
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Color blindness
Correct Answer
A. Down syndromeExplanation
A trisomy of chromosome 21 causes Down syndrome. Down syndrome is a genetic disorder that occurs when an individual has three copies of chromosome 21 instead of the usual two. This extra genetic material leads to various physical and cognitive developmental delays and characteristics associated with the condition.Rate this question:
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- 9.
Since the allele for colorblindness is located on the X chromosome, colorblindness
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Cannot be inherited.
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Occurs only in adults.
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Is sex-linked.
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None of the above.
Correct Answer
A. Is sex-linked.Explanation
Colorblindness is a genetic disorder caused by an abnormality in the X chromosome. Since females have two X chromosomes and males have one X and one Y chromosome, the inheritance pattern of colorblindness is sex-linked. This means that the gene for colorblindness is more commonly passed from a carrier mother to her son, as the son inherits his X chromosome from his mother. Therefore, the correct answer is that colorblindness is sex-linked.Rate this question:
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- 10.
Organisms that have two identical alleles for a particular trait are said to be
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Hybrid.
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Heterozygous.
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Homozygous.
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Dominant.
Correct Answer
A. Homozygous.Explanation
Organisms that have two identical alleles for a particular trait are said to be homozygous. This means that both alleles for the trait are the same, either both dominant or both recessive. In contrast, heterozygous organisms have two different alleles for the trait, while hybrid refers to the offspring of two different species or varieties. Dominant refers to the allele that is expressed in the phenotype, regardless of whether the organism is homozygous or heterozygous for that allele.Rate this question:
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- 11.
Horse skeleton fossils indicate that the size of horses increased over time. Which statement best explains this fossil record?
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Smaller horses bred with larger horses, creating hybrids.
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Smaller horses were infected by a fatal virus early in their history.
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Larger horses consumed the food supply of the smaller horses.
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Larger horses produced a slightly greater number of surviving offspring.
Correct Answer
A. Larger horses produced a slightly greater number of surviving offspring.Explanation
The fossil record suggests that the size of horses increased over time, indicating a trend towards larger horses. The best explanation for this is that larger horses produced a slightly greater number of surviving offspring. This means that the genes for larger size were more successful in being passed on to the next generation, leading to an overall increase in the size of horses over time.Rate this question:
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- 12.
Which of the following is a function of the cell membrane?
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Breaks down lipids, carbohydrates, and proteins from foods
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Stores water, salt, proteins, and carbohydrates
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Keeps the cell wall in place
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Regulates which materials enter and leave the cell
Correct Answer
A. Regulates which materials enter and leave the cellExplanation
The cell membrane acts as a selective barrier, controlling the movement of substances into and out of the cell. It regulates the entry and exit of molecules, ions, and other materials, allowing essential nutrients to enter and waste products to exit. This function is vital for maintaining homeostasis and ensuring the cell's proper functioning. The other options mentioned, such as breaking down nutrients or storing substances, are not primarily associated with the cell membrane's role.Rate this question:
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- 13.
The process by which organisms keep their internal conditions fairly constant is called
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Metabolism.
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Homeostasis.
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Photosynthesis.
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Evolution.
Correct Answer
A. Homeostasis.Explanation
Homeostasis refers to the ability of organisms to maintain a stable internal environment despite external changes. It involves various physiological processes that regulate temperature, pH, blood sugar levels, and other vital parameters within a narrow range. Metabolism, on the other hand, refers to the chemical reactions that occur in the body to convert food into energy. Photosynthesis is the process by which plants convert sunlight into energy, while evolution refers to the gradual change in species over time. Therefore, homeostasis is the most appropriate answer as it directly relates to the concept of maintaining internal conditions.Rate this question:
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- 14.
The active site of an enzyme is
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Where the reactant fits into the enzyme
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Where the enzymes and molecule bond together
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When the balance of living organisms affects the enzyme
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The same shape in all enzymes
Correct Answer
A. Where the reactant fits into the enzymeExplanation
The active site of an enzyme is where the reactant fits into the enzyme. Enzymes are proteins that catalyze chemical reactions in living organisms. The active site is a specific region on the enzyme where the reactant, also known as the substrate, binds and undergoes a chemical reaction. This binding is highly specific and complementary, like a lock and key, allowing the enzyme to perform its catalytic function. The active site provides a favorable environment for the reaction to occur, stabilizes the transition state, and promotes the formation of the product.Rate this question:
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- 15.
In the Punnett square shown in Figure 11–1, which of the following is true about the offspring resulting from the cross?
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About half are expected to be short.
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All are expected to be short.
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About half are expected to be tall.
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All are expected to be tall.
Correct Answer
A. All are expected to be tall.Explanation
Based on the Punnett square shown in Figure 11-1, it can be inferred that all offspring resulting from the cross will be tall. This is because both parents in the cross are homozygous dominant for the tall trait, meaning they only carry the dominant allele for tallness. As a result, all of their offspring will inherit the dominant allele and express the tall phenotype.Rate this question:
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- 16.
During which phase of mitosis do spindle fibers separate (pull apart) sister chromatids?
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Anaphase
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Metaphase
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Prophase
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Telophase
Correct Answer
A. AnaphaseExplanation
Anaphase pulls apart sister chromatids.Rate this question:
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- 17.
Which of the following characteristics of living things best explains why birds fly south for the winter?
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Living things are based on a universal genetic code.
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Living things are made up of units called cells.
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Living things respond to their environment.
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Living things maintain internal balance.
Correct Answer
A. Living things respond to their environment.Explanation
Birds flying south for the winter is a behavior that demonstrates how living things respond to their environment. In response to changes in temperature and food availability, birds instinctively migrate to more favorable conditions. This behavior allows them to survive and thrive in different environments throughout the year.Rate this question:
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- 18.
A flagellated protozoan lives within the intestines of a termite and helps it digest wood. What type of relationship most likely exists between the protozoan and the termite?
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Competitive
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Mutualistic
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Parasitic
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Predatory
Correct Answer
A. MutualisticExplanation
The termite and the flagellated protozoan have a mutualistic relationship. This means that both organisms benefit from their interaction. The protozoan helps the termite digest wood, which is its main source of nutrition, while the termite provides a suitable environment and a constant food supply for the protozoan. Both organisms rely on each other for survival, making their relationship mutualistic.Rate this question:
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- 19.
Unlike DNA, RNA contains
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Adenine
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Uracil
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Phosphate groups
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Thymine
Correct Answer
A. UracilExplanation
RNA is a nucleic acid similar to DNA, but it contains uracil instead of thymine. Uracil is one of the four nitrogenous bases found in RNA, along with adenine, guanine, and cytosine. Thymine, on the other hand, is found exclusively in DNA. The presence of uracil in RNA allows it to pair with adenine during transcription and translation processes, forming RNA molecules that are crucial for protein synthesis. Therefore, uracil is a characteristic feature of RNA that distinguishes it from DNA.Rate this question:
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- 20.
These diagrams represent different stages of animal cell division. From start to finish, what is the correct order of the stages?
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2, 4, 3, 1
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2, 3, 4, 1
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3, 2, 1, 4
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3, 1, 2, 4
Correct Answer
A. 2, 4, 3, 1Explanation
Prophase (chromosomes condense & nuclear membrane disappears)
Metaphase (chromosomes line up in the MIDDLE)
Anaphase (chromosomes are pulled APART)
Telophase (2 nuclear membranes form & cytokinesis occursRate this question:
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- 21.
Which of the following has the stages of the cell cycle in the correct sequence?
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G1, G2, S, Prophase, Anaphase, Metaphase, Telophase, Cytokinesis
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G1, S, G2, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis
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G1, S, G2, Cytokinesis, Prophase, Metaphase, Anaphase, Telophase
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S, G1, G2, Metaphase, Anaphase, Telophase, Prophase, Cytokinesis
Correct Answer
A. G1, S, G2, Prophase, Metaphase, Anaphase, Telophase, CytokinesisExplanation
I = Interphase (G1, S, G2)
Play = Prophase
My = Metaphase
Accordion = Anaphase
To = Telophase
Cats = CytokinesisRate this question:
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- 22.
The idea that life can come from non-living matter is called ___.
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Evolution
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Spontaneous generation
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Autotrophism
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Biogenesis
Correct Answer
A. Spontaneous generationExplanation
Spontaneous generation refers to the belief that living organisms can arise from non-living matter. This concept was widely accepted in ancient times but was later disproven by experiments conducted by Louis Pasteur in the 19th century. Pasteur's experiments showed that life only arises from pre-existing life, a principle known as biogenesis. Therefore, the correct answer is spontaneous generation.Rate this question:
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- 23.
In an experiment, a scientist filled 2 open flasks, as shown in the figures, with broth and boiled the broth until it became clear. He then left the flasks open for several days. Which results showed that spontaneous generation did not occur? {C}{C}
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The broth in Flask A became cloudy, and the broth in Flask B remained clear.
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The broth in Flask A remained clear, and the broth in Flask B became cloudy.
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The broth in both Flasks A and B became cloudy.
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The broth in both Flasks A and B remained clear.
Correct Answer
A. The broth in Flask A became cloudy, and the broth in Flask B remained clear.Explanation
The correct answer indicates that spontaneous generation did not occur because the broth in Flask A became cloudy, suggesting the growth of microorganisms, while the broth in Flask B remained clear, indicating the absence of any spontaneous generation. This result supports the idea that microorganisms were present in the environment and contaminated Flask A, rather than being spontaneously generated.Rate this question:
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- 24.
Which structure in the cell is responsible for providing the cell with energy through the process of cellular respiration?
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Chloroplast
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Mitochondria
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Lysosome
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Vacuole
Correct Answer
A. MitochondriaExplanation
Mitochondria are responsible for providing the cell with energy through the process of cellular respiration. This organelle is often referred to as the "powerhouse" of the cell because it produces the majority of the cell's energy in the form of adenosine triphosphate (ATP). Mitochondria have their own DNA and are capable of carrying out aerobic respiration, a process that involves breaking down glucose and other organic molecules to generate ATP. This energy is then used by the cell to perform various functions and maintain its overall metabolic activities.Rate this question:
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- 25.
What is the term used to describe the energy needed to get a reaction started?
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Adhesion energy
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Activation energy
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Cohesion energy
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Chemical energy
Correct Answer
A. Activation energyExplanation
Activation energy is the term used to describe the energy needed to get a reaction started. It is the minimum amount of energy required for a chemical reaction to occur. Activation energy is necessary to break the bonds between reactant molecules and initiate the formation of new bonds in the products. Without sufficient activation energy, the reaction will not proceed. Adhesion energy refers to the energy required to separate two different substances, cohesion energy is the energy required to separate similar substances, and chemical energy refers to the potential energy stored in chemical bonds.Rate this question:
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- 26.
In the food web above, which is a correct sequence for the flow of energy in a food chain containing the leopard seal?
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Phytoplankton --> krill --> penguin --> leopard seal
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Smaller toothed whales --> leopard seal --> fish --> krill
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Other birds --> leopard seal --> other seals --> baleen whale
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Carnivorous zooplankton --> other seals --> leopard seal --> smaller toothed whales
Correct Answer
A. Phytoplankton --> krill --> penguin --> leopard sealExplanation
The correct sequence for the flow of energy in a food chain containing the leopard seal is phytoplankton --> krill --> penguin --> leopard seal. This sequence follows the typical pattern of energy transfer in a food chain, where energy flows from producers (phytoplankton) to primary consumers (krill) to secondary consumers (penguins) and finally to tertiary consumers (leopard seals).Rate this question:
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- 27.
What characteristic of early autotrophs gave them an advantage over early heterotrophs?
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They ate heterotrophs.
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They produced spores.
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They made their own food.
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They reproduced asexually.
Correct Answer
A. They made their own food.Explanation
Early autotrophs had an advantage over early heterotrophs because they were capable of producing their own food through processes like photosynthesis. This ability allowed them to convert sunlight and simple inorganic molecules into energy-rich organic compounds, providing them with a constant source of nutrition. In contrast, early heterotrophs relied on consuming other organisms for sustenance, making them dependent on the availability of prey. The ability to produce their own food gave autotrophs a greater independence and survival advantage in environments where food sources were scarce or unpredictable.Rate this question:
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- 28.
The organisms of what kingdom possess these traits?
- Eukaryotic cells
- Photosynthetic
- Cellulose cell walls
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Eubacteria
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Fungi
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Plantae
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Monera
Correct Answer
A. PlantaeExplanation
The organisms that possess these traits are from the Plantae kingdom. They have eukaryotic cells, which means their cells have a nucleus and other membrane-bound organelles. They are also photosynthetic, meaning they can convert sunlight into energy through the process of photosynthesis. Additionally, they have cellulose cell walls, which provide structural support and protection for the cells.Rate this question:
- 29.
Lions and tigers both belong to genus Panthera. Cheetahs belong to the genus Acinonyx. Scientists group these 3 types of cats together at the next taxonomic level. What is the most specific taxonomic level tat lions, cheetahs, and tigers share?
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Class
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Family
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Kingdom
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Order
Correct Answer
A. FamilyExplanation
Lions, cheetahs, and tigers share the most specific taxonomic level of Family. This is because they all belong to the same family called Felidae, which includes all the big cats. The family level is more specific than Kingdom, Phylum, Class, and Order, as it groups organisms that are more closely related to each other.Rate this question:
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- 30.
Without enzymes, the chemical reactions in the body would
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Happen too fast
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Occur at much the same rate as they do with enzymes
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Require a different pH
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Occur too slowly to support life processes
Correct Answer
A. Occur too slowly to support life processesExplanation
Enzymes are biological catalysts that speed up chemical reactions in the body. Without enzymes, these reactions would occur too slowly to support life processes. Enzymes lower the activation energy required for a reaction to occur, allowing it to happen at a faster rate. Therefore, the absence of enzymes would result in a significant decrease in the speed of reactions, which would be insufficient to sustain vital life processes.Rate this question:
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- 31.
A scientist places a cell in a solution, and over time the cell gains mass and swells. What is the most likely explanation for the cell’s gain in mass?
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The solution is hypertonic to the cell
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The solution and the cell have equal concentrations of solutes
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The solution is hypotonic to the cell
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The solution and the cell have equal concentrations of water
Correct Answer
A. The solution is hypotonic to the cellExplanation
The cell gains mass and swells because the solution is hypotonic to the cell. In a hypotonic solution, there is a lower concentration of solutes outside the cell compared to inside the cell. This concentration gradient causes water to move into the cell through osmosis, resulting in an increase in the cell's mass and causing it to swell.Rate this question:
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- 32.
What animals eat both producers and consumers?
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Herbivores
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Omnivores
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Carnivores
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Autotrophs
Correct Answer
A. OmnivoresExplanation
Omnivores are animals that have the ability to eat both producers (plants) and consumers (other animals). They have a diverse diet that includes both plant matter and meat. This makes them adaptable and able to obtain nutrients from a variety of sources. Some examples of omnivores include bears, raccoons, and humans.Rate this question:
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- 33.
Dr. Romero is raising 3 types of damselfishes in separate aquariums: 2 from the Atlantic Ocean and 1 from the Pacific Ocean. This table summarizes the information she gathered through observations and breeding experiments. Based on the most commonly accepted definition of a species, how many different species of damselfishes is Dr. Romero raising, and which fish are they?
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1 species: Fish A, B, and C are all members of a single species
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2 species: Fish A and B are a single species; Fish C is a separate species
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2 species: Fish A and C are a single species; Fish B is a separate species
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3 species: Fish A, B, and C are all members of separate species
Correct Answer
A. 2 species: Fish A and C are a single species; Fish B is a separate speciesExplanation
Dr. Romero is raising two different species of damselfishes. Fish A and C are classified as the same species, while Fish B is considered a separate species. This conclusion is based on the most commonly accepted definition of a species, which states that members of the same species can interbreed and produce fertile offspring, while members of different species cannot. Therefore, since Fish A and C can interbreed and produce fertile offspring, they are considered the same species, while Fish B cannot interbreed with them and is therefore a separate species.Rate this question:
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- 34.
An animal has these characteristics:
- Many more than 8 jointed legs on a segmented body
- 2 pairs of legs attached to each body segment
- Lacks biting jaws
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Dragonfly
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Millipede
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Sea Star
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Slug
Correct Answer
A. MillipedeExplanation
A millipede fits the given characteristics because it has many more than 8 jointed legs on a segmented body, with 2 pairs of legs attached to each body segment. Additionally, millipedes lack biting jaws, which distinguishes them from other options like the dragonfly, sea star, and slug.Rate this question:
- 35.
In a DNA molecule, what base is paired with cytosine?
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Thymine
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Guanine
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Adenine
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Uracil
Correct Answer
A. GuanineExplanation
Cytosine is one of the four bases found in DNA. It forms a base pair with guanine. In DNA, cytosine always pairs with guanine through hydrogen bonding. This pairing is essential for maintaining the structure and stability of the DNA molecule. The complementary base pairing between cytosine and guanine is a fundamental aspect of DNA replication and transcription processes.Rate this question:
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- 36.
Which of the following is the best explanation for the observation that females rarely get the disease hemophilia?
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Large quantities of male hormones are necessary in order for the allele carrying the disease to be expressed.
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Female fetuses that carry the allele for the disease die before birth.
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A female could get the disease only by having a mother who is a carrier and a father who has the disease. Since most males with the disease do not survive to reproductive age, this is an extremely unlikely event.
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A female could get the disease only by having parents who are both carriers of the disease. Because females cannot be carriers, this is an impossible event.
Correct Answer
A. A female could get the disease only by having a mother who is a carrier and a father who has the disease. Since most males with the disease do not survive to reproductive age, this is an extremely unlikely event.Explanation
Hemophilia is an X-linked recessive disorder, which means it is carried on the X chromosome. Females have two X chromosomes, so in order for them to get the disease, they would need to inherit the allele from both parents. Since most males with the disease do not survive to reproductive age, it is unlikely for a female to have a father with hemophilia. Therefore, the best explanation is that a female could get the disease only by having a mother who is a carrier and a father who has the disease.Rate this question:
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- 37.
Lazzaro Spallanzani and Louis Pasteur both performed experiments hoping to disprove spontaneous generation. What conditions existed in Pasteur’s experiment that did not exist in Spallanzani’s?
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Neither air nor microoganisms could enter the flasks.
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Air could enter the flasks, but no microorganisms could enter.
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Both air and microorganisms could enter the flasks.
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No air could enter the flasks, but microorganisms could enter.
Correct Answer
A. Air could enter the flasks, but no microorganisms could enter.Explanation
In Pasteur's experiment, air could enter the flasks, but no microorganisms could enter. This condition was different from Spallanzani's experiment, where neither air nor microorganisms could enter the flasks. By allowing air to enter the flasks, Pasteur was able to demonstrate that it was not the air itself that caused spontaneous generation, but rather the presence of microorganisms in the air. This helped to disprove the theory of spontaneous generation and support the concept of biogenesis.Rate this question:
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- 38.
A substance that accelerates the rate of a chemical reaction is called a(an)
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Catalyst
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Lipid
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Molecule
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Protein
Correct Answer
A. CatalystExplanation
A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It works by providing an alternative pathway for the reaction to occur with lower activation energy. This allows the reaction to proceed faster and more efficiently. Catalysts are commonly used in various industries and biological systems to speed up reactions and save energy.Rate this question:
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- 39.
Enzymes affect the reactions in living cells by changing the
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Products of the reaction
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Speed of the reaction
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Temperature of the reaction
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PH of the reaction
Correct Answer
A. Speed of the reactionExplanation
Enzymes affect the reactions in living cells by changing the speed of the reaction. Enzymes are biological catalysts that speed up chemical reactions by lowering the activation energy required for the reaction to occur. They do not alter the products of the reaction, the temperature, or the pH of the reaction. Instead, enzymes provide an alternative pathway for the reaction to proceed more quickly, allowing biological processes to occur at a faster rate.Rate this question:
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- 40.
Which of the following is the best definition for a substrate?
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A reactant that an enzyme binds with to carry out a reaction
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An enzyme that has an active site
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A reactant that an active site acts on
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None of the answer choices are correct
Correct Answer
A. A reactant that an enzyme binds with to carry out a reactionExplanation
A substrate is defined as a reactant that an enzyme binds with to carry out a reaction. Enzymes are biological catalysts that facilitate chemical reactions by binding to specific substrates at their active sites. The enzyme-substrate complex formed allows the enzyme to lower the activation energy required for the reaction to occur, thus speeding up the reaction. Therefore, the best definition for a substrate is a reactant that an enzyme binds with to carry out a reaction.Rate this question:
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- 41.
Genes are sections of DNA that contain instructions for assembling
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Purines
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Nucleosomes
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Proteins
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Pyrimidines
Correct Answer
A. ProteinsExplanation
Genes are sections of DNA that contain instructions for assembling proteins. Proteins are crucial molecules that perform various functions in the body, such as enzymes for biochemical reactions, structural components for cells and tissues, and signaling molecules for communication between cells. Therefore, genes provide the necessary information for the synthesis of proteins, which are essential for the proper functioning and development of organisms. Purines and pyrimidines are types of nucleotides that make up DNA, while nucleosomes are structures formed by DNA and proteins. However, it is proteins that are directly encoded by genes.Rate this question:
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- 42.
In humans, pigmented skin is dominant to non-pigmented skin (albinism). What is the genotype of an individual with albinism?
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Carrier
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Heterozygous
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Homozygous dominant
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Homozygous recessive
Correct Answer
A. Homozygous recessiveExplanation
An individual with albinism has a genotype of homozygous recessive. This means that both of their alleles for the pigmented skin trait are recessive, resulting in the absence of pigmentation in their skin. Albinism is a genetic condition that is inherited when both parents pass on the recessive allele for non-pigmented skin.Rate this question:
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- 43.
Based on their taxonomic classification, which 2 organisms share the most recent common ancestor?
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Squid and octopus (same class)
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Lobster and eel (same kingdom)
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Chimpanzee and gorilla (same family)
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Iguana and mouse (same phylum)
Correct Answer
A. Chimpanzee and gorilla (same family)Explanation
Chimpanzees and gorillas belong to the same family, which indicates that they share a more recent common ancestor compared to the other pairs mentioned. Taxonomic classification is based on evolutionary relationships, and organisms in the same family are more closely related than those in the same class, kingdom, or phylum. Therefore, chimpanzees and gorillas are the two organisms that share the most recent common ancestor among the given options.Rate this question:
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- 44.
How do enzymes speed up chemical reactions?
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By reducing activation energy
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By reducing the energy produced by the reaction
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By increasing activation energy
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By increasing energy produced by the reaction
Correct Answer
A. By reducing activation energyExplanation
Enzymes speed up chemical reactions by reducing activation energy. Activation energy is the amount of energy required to start a chemical reaction. Enzymes lower this energy barrier, allowing reactions to occur more easily and quickly. They do this by binding to the reactant molecules and bringing them closer together, facilitating the formation of new bonds and the breaking of existing ones. This lowers the energy needed for the reaction to proceed, making it more favorable and efficient.Rate this question:
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- 45.
Biochemists have created an artificial cell membrane that they hope to insert into artificial red blood cells for future dehydration and transportation into outer space. When scientists stain natural cell membranes with a heavy metal, they can view the membranes with an electron microscope. The heavy metal stains the polar hydrophilic heads of phospholipid membranes. If the artificial membranes resemble natural membranes, what area(s), when viewed under a microscope, would appear stained? (Note: Shading represents stains.)
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A
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B
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C
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D
Correct Answer
A. CExplanation
The correct answer is C because if the artificial membranes resemble natural membranes, the polar hydrophilic heads of phospholipid membranes would appear stained when viewed under a microscope. This is because the heavy metal stains the polar hydrophilic heads of phospholipid membranes in natural cell membranes.Rate this question:
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- 46.
The presence of what cellular structure distinguishes a plant cell from an animal cell?
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Cell membrane
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Chloroplast
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Mitochondrion
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Nucleus
Correct Answer
A. ChloroplastExplanation
Chloroplasts are the organelles found in plant cells that are responsible for photosynthesis. They contain chlorophyll, which allows plants to convert sunlight into energy. Animal cells do not have chloroplasts, so the presence of chloroplasts distinguishes plant cells from animal cells.Rate this question:
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- 47.
During which phase of mitosis do the chromosomes line up along the equator (middle) of the dividing cell?
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Metaphase
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Telophase
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Anaphase
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Prophase
Correct Answer
A. MetaphaseExplanation
Chromosomes are pulled to the equator (middle) of the cell during metaphase. Metaphase = MiddleRate this question:
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- 48.
Which of the following factors affects enzyme activity?
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Environmental factors
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Cofactors (Coenzymes)
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Enzyme Inhibitors
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All of the answer choices are correct
Correct Answer
A. All of the answer choices are correctExplanation
All of the answer choices are correct because all the factors listed - environmental factors, cofactors (coenzymes), and enzyme inhibitors - can affect enzyme activity. Environmental factors such as temperature and pH can alter the shape and function of enzymes. Cofactors, like vitamins and minerals, are necessary for some enzymes to function properly. Enzyme inhibitors can bind to enzymes and prevent them from carrying out their normal catalytic activity. Therefore, all of these factors can have an impact on enzyme activity.Rate this question:
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- 49.
Megan examines a liver cell and observes an organelle with many smooth-sided channels. Which activity would identify this organelle as the Golgi apparatus?
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Digestion of macromolecules and old organelles
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Detoxification of poisonous molecules within the cell
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Harvesting of energy from organic molecules to make ATP
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Processing and packaging of cellular materials prior to export
Correct Answer
A. Processing and packaging of cellular materials prior to exportExplanation
The Golgi apparatus is responsible for processing and packaging cellular materials prior to export. It contains smooth-sided channels, which are involved in modifying, sorting, and packaging proteins and lipids into vesicles for transport to other parts of the cell or for secretion outside the cell. This activity of the Golgi apparatus is essential for maintaining the proper functioning and organization of the cell.Rate this question:
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.png "Biochemists have created an artificial cell membrane that they hope to insert into artificial red blood cells for future dehydration and transportation into outer space.
When scientists stain natural cell membranes with a heavy metal, they can view the membranes with an electron microscope. The heavy metal stains the polar hydrophilic heads of phospholipid membranes. If the artificial membranes resemble natural membranes, what area(s), when viewed under a microscope, would appear stained? (Note: Shading represents stains.)")
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Mar 21, 2023Quiz Edited by
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Apr 23, 2013Quiz Created by
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