Fall 2016 Bio 1 Midterm Exam Review

Enzymes affect the rate of a chemical reaction. Enzymes are biological catalysts that speed up the rate of chemical reactions by lowering the activation energy required for the reaction to occur. They do this by binding to the reactant molecules and facilitating the formation of the transition state, which then leads to the formation of products. Therefore, enzymes play a crucial role in increasing the rate at which chemical reactions proceed in biological systems.

The cell wall is not found in an animal cell. While both plant and bacterial cells have a cell wall, animal cells do not possess this feature. Animal cells are surrounded by a plasma membrane, which provides structure and protection to the cell. The cell wall, on the other hand, is a rigid layer found outside the plasma membrane in plant cells and some bacteria, providing additional support and protection.

The stage of mitosis illustrated on the right is telophase. This can be determined based on the characteristics of telophase, such as the formation of a nuclear envelope around each set of chromosomes, the decondensation of chromosomes, and the formation of a cleavage furrow or cell plate.

not-available-via-ai

The correct answer is cell -> tissue -> organ -> organ system. This sequence represents the progression from the least complex structure to the most complex structure. At the cellular level, individual cells are the basic building blocks of life. Tissues are formed when similar cells come together to perform a specific function. Organs are composed of different types of tissues working together to carry out specific functions. Finally, organ systems are made up of multiple organs working together to perform complex functions necessary for the survival of an organism.

Lysosomes contain enzymes that break down old cell parts. Lysosomes are membrane-bound organelles that function as the cell's recycling centers. They contain a variety of hydrolytic enzymes that are capable of breaking down various biological molecules, including proteins, nucleic acids, carbohydrates, and lipids. These enzymes are responsible for the degradation and recycling of cellular waste, as well as the breakdown of old or damaged organelles.

The correct answer is "regulate what goes in/out of a cell." The diagram likely depicts a cell membrane or a similar structure that controls the movement of substances into and out of the cell. This function is essential for maintaining homeostasis and allowing the cell to selectively transport molecules and ions across its boundary.

Binary fission is the most common form of reproduction among prokaryotes. In this process, a single prokaryotic cell divides into two identical daughter cells. It involves the replication of the genetic material and the splitting of the cell into two separate cells. This method of reproduction allows prokaryotes to rapidly increase their population and is an efficient way for them to reproduce in favorable conditions. Sexual reproduction, budding, and fragmentation are not as common among prokaryotes as binary fission.

Protein polymers are made of a series of amino acids. Amino acids are the building blocks of proteins and are linked together through peptide bonds to form long chains. These chains then fold into specific three-dimensional structures, which determine the function of the protein. Monosaccharides are the building blocks of carbohydrates, histones are proteins involved in DNA packaging, and DNA strands are nucleic acids that carry genetic information. Therefore, the correct answer is amino acids.

During anaphase, sister chromatids separate from each other and move towards opposite poles of the cell. This is facilitated by the shortening of microtubules attached to the kinetochores of each chromatid. As the microtubules shorten, the sister chromatids are pulled apart, ensuring that each daughter cell receives an identical set of chromosomes. Therefore, anaphase is the phase of mitosis in which sister chromatids separate from each other.

During metaphase, the chromosomes line up in the middle of the cell. This is a characteristic of metaphase because it is the stage of mitosis where the chromosomes, which have already replicated during interphase, align themselves along the equatorial plane of the cell. This alignment is crucial for ensuring that each daughter cell receives the correct number of chromosomes during cell division. The other options, such as the breakdown of the nuclear membrane, the separation of sister chromatids, or the splitting of the cytoplasm, occur during other stages of mitosis.

DNA and RNA are two types of nucleic acids. Nucleic acids are macromolecules that store and transmit genetic information in living organisms. DNA (deoxyribonucleic acid) is responsible for storing genetic information, while RNA (ribonucleic acid) plays a role in protein synthesis and gene expression. Proteins, carbohydrates, and lipids are other types of biomolecules, but they are not specifically related to storing and transmitting genetic information like nucleic acids.

The nucleus is the storehouse for most of a cell's genetic information. It contains the cell's DNA, which carries the instructions for the cell's functions and characteristics. The DNA is organized into structures called chromosomes, which are located within the nucleus. The nucleus also regulates the cell's activities and controls the expression of genes. Therefore, the nucleus is responsible for storing and controlling the cell's genetic information.

A membrane-bound sac that contains digestive enzymes is called a lysosome. Lysosomes are organelles found in animal cells that function as the cell's recycling center. They break down various macromolecules, such as proteins, nucleic acids, and carbohydrates, into smaller molecules that can be reused by the cell. The digestive enzymes within the lysosome are highly acidic and can break down a wide range of substances. Lysosomes also play a crucial role in the immune system by destroying foreign substances, such as bacteria and viruses, engulfed by the cell.

A solute is a substance that dissolves in a solvent. When a solute is added to a solvent, it disperses and becomes evenly distributed throughout the solvent, forming a solution. The solute particles become surrounded by solvent particles, breaking down the solute into individual molecules or ions. This process is known as dissolution. The solute can be a solid, liquid, or gas, and it can dissolve in various types of solvents, such as water, alcohol, or oil. The solute-solvent interaction is essential in many chemical and biological processes, as it allows for the transportation of substances and the formation of solutions.

The stage of mitosis illustrated on the right is prophase. Prophase is characterized by the condensation of chromatin into visible chromosomes, the breakdown of the nuclear membrane, and the formation of the mitotic spindle. In the image, these features can be observed, indicating that the cell is in prophase.

The structures labeled B would be made of protein because lipids are not typically involved in structural components, cellulose is a carbohydrate found in plant cell walls, and fatty acid chains are components of lipids rather than structural components themselves. Protein is known to be involved in the formation of various structural components in cells, such as the cytoskeleton and extracellular matrix.

The correct answer is anaphase because in the image on the right, the sister chromatids are separating and moving towards opposite poles of the cell. This is a characteristic feature of anaphase in mitosis.

G zero refers to the phase in the cell cycle where cells temporarily stop dividing and enter a non-dividing state. During this phase, cells may remain in a resting state or carry out specialized functions without undergoing mitosis. This phase is important for cells that have completed their division cycle or have reached a stage where they no longer need to divide. Thus, the correct answer is G zero.

Ribosomes can be found on the surface of the endoplasmic reticulum. This is because the endoplasmic reticulum is involved in protein synthesis, and ribosomes are the cellular structures responsible for protein synthesis. The endoplasmic reticulum provides a platform for ribosomes to attach and synthesize proteins, which can then be transported and modified within the cell. Therefore, ribosomes are the correct answer as they are directly associated with the endoplasmic reticulum.

During mitosis, the process of organizing and condensing DNA into its compact form takes place. Mitosis is the phase of the cell cycle where the cell divides into two identical daughter cells. This process involves several stages, including prophase, metaphase, anaphase, and telophase. In prophase, the DNA condenses into tightly coiled structures called chromosomes. These chromosomes are then aligned at the equator of the cell during metaphase. Therefore, mitosis is the correct answer as it specifically refers to the phase where DNA condensation occurs.

Chloroplasts are the correct answer because they are unique to plant cells and are responsible for photosynthesis, the process by which plants convert sunlight into energy. Chloroplasts contain chlorophyll, a pigment that gives plants their green color and allows them to absorb sunlight. They are not found in animal cells or other types of cells.

G1 phase is the first phase of the cell cycle, where the cell grows in size and carries out its normal functions. During this phase, the cell prepares for DNA replication and enters the S phase. However, the main characteristic of G1 phase is cell growth and normal function, as it is the time when the cell acquires the necessary nutrients and energy to support its growth and perform its regular activities.

A vesicle is a membrane-bound sac that is responsible for transporting substances into and out of cells. It acts as a small transport vehicle within the cell, allowing molecules to be moved from one location to another. Vesicles are involved in various cellular processes such as secretion, exocytosis, endocytosis, and intracellular transport. They play a crucial role in maintaining the homeostasis of the cell by regulating the movement of molecules and maintaining the integrity of the cell membrane.

Histones are the proteins that organize and condense long strands of DNA into tight coils. They play a crucial role in DNA packaging, helping to compact the DNA molecule and regulate gene expression. Histones form complexes called nucleosomes, around which the DNA wraps, creating a structure known as chromatin. This compact packaging allows for efficient storage and protection of DNA within the cell nucleus. Telomeres are repetitive DNA sequences at the ends of chromosomes, centromeres are regions of DNA that help in chromosome segregation during cell division, and chromatids are duplicated copies of a chromosome.

During the S phase of the cell cycle, DNA replication occurs. This means that the DNA molecule is duplicated, resulting in two identical copies. This is an essential process for cell division as each new cell needs to have a complete set of genetic information. The other options mentioned, such as cell growth and preparation for mitosis, and the reforming of the nuclear membrane, are not specific to the S phase and can occur during other stages of the cell cycle as well.

Chemical reactions involve the breaking and forming of chemical bonds, resulting in the transformation of substances into different substances. During a chemical reaction, the bonds between atoms in the reactants are broken, and new bonds are formed to create the products. This process can involve various types of reactions, such as synthesis, decomposition, combustion, and more. Therefore, it is through chemical reactions that substances undergo changes and are converted into different substances.

Cytokinesis is the final stage of the cell cycle, following mitosis or meiosis, in which the cytoplasm of a cell divides to form two daughter cells. It is responsible for completing the cell cycle and ensuring that each daughter cell receives a copy of the genetic material. Therefore, the statement "completes the cell cycle" is true for cytokinesis.

A pH of 12 would be considered a strong base. pH is a measure of the acidity or alkalinity of a solution, with values ranging from 0 to 14. A pH of 7 is considered neutral, below 7 is acidic, and above 7 is alkaline. The higher the pH value, the more alkaline the solution is. A pH of 12 indicates a highly alkaline solution, making it a strong base.

Cohesion refers to the attraction between substances of the same kind. This force allows molecules of the same substance to stick together, creating surface tension and forming droplets. It is responsible for the ability of water to form beads on a surface and for the movement of water through plants. Adhesion, on the other hand, refers to the attraction between different substances. Ionic bonding is a type of chemical bonding that occurs between ions with opposite charges. "Chemical friendship" is not a scientific term and does not accurately describe the concept of attraction between substances of the same kind.

A catalyst is a substance that lowers the activation energy required for a chemical reaction to occur. It does this by providing an alternative pathway with a lower energy barrier for the reaction to proceed. By decreasing the activation energy, a catalyst increases the rate of the reaction without being consumed in the process. Therefore, a catalyst is the correct answer because it effectively reduces the energy barrier and facilitates the reaction.

The term "metaphase plate" refers to the imaginary plane in the cell where chromosomes align during metaphase, which is a stage of cell division. This plate is crucial for ensuring that each daughter cell receives the correct number of chromosomes during cell division. The other options, such as "cell plate," "cleavage furrow," and "envelope," do not accurately describe the specific plane where chromosomes line up during metaphase.

The structure labeled C in Fig. 3.3 is the Endoplasmic Reticulum. The Endoplasmic Reticulum is a network of membranes found in the cytoplasm of eukaryotic cells. It plays a key role in the synthesis, folding, and transport of proteins, as well as lipid metabolism and detoxification of drugs and toxins. It can be classified into two types: rough endoplasmic reticulum (RER), which is studded with ribosomes and involved in protein synthesis, and smooth endoplasmic reticulum (SER), which lacks ribosomes and is involved in lipid synthesis and detoxification.

Cytokinesis is the final stage of cell division, where the cytoplasm of the parent cell divides into two daughter cells. This process ensures that each daughter cell receives the necessary organelles and cytoplasmic components to function independently. The nuclear membrane breaks down during prophase, chromosomes line up in the middle during metaphase, and sister chromatids are pulled to opposite sides during anaphase. However, it is during cytokinesis that the cytoplasm physically splits, allowing for the formation of two separate cells.

Water molecules are polar, meaning they have a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom. In a hydrogen bond, the positive region of one water molecule is attracted to the negative region of another water molecule. This attraction is due to the electrostatic forces between the partially positive hydrogen atom and the partially negative oxygen atom. Therefore, the correct answer is hydrogen bond.

A substance that releases protons (H+ ions) in solution is known as an acid. Acids are characterized by their ability to increase the concentration of H+ ions when dissolved in water. They typically have a sour taste and can react with metals, turn litmus paper red, and have a pH value less than 7. Examples of common acids include hydrochloric acid (HCl) and sulfuric acid (H2SO4).

Synthesis is not part of the M phase. The M phase, also known as the mitotic phase, is the phase of the cell cycle where cell division occurs. It consists of several stages including prophase, metaphase, anaphase, and telophase. During these stages, the cell undergoes processes such as condensation of chromosomes, alignment of chromosomes at the cell equator, separation of sister chromatids, and formation of two daughter cells. Synthesis, on the other hand, is part of the interphase, specifically the S phase, where DNA replication takes place.

A molecule is the smallest unit of a substance that retains all of its physical and chemical properties. It can be made up of a single element or multiple elements bonded together. This means that a molecule can exist as an individual entity or as a component of a larger substance.

An ionic bond forms through the electrical force between oppositely charged ions. In an ionic bond, one atom donates electrons to another atom, resulting in the formation of positively charged cations and negatively charged anions. These ions are held together by electrostatic attraction, creating a strong bond between them. Covalent bonds involve the sharing of electrons between atoms, hydrogen bonds are formed between a hydrogen atom and an electronegative atom, and James Bond is a fictional character unrelated to chemical bonding.

The structure labeled F in Fig. 3.3 is responsible for holding water. This means that it has the function of storing and retaining water within the organism or structure depicted in the figure.

A substance that removes protons (H+ ions) from a solution is a base. Bases are substances that can accept protons or donate pairs of electrons. They have a higher pH value and can neutralize acids by reacting with them to form water and a salt. By removing protons from a solution, bases increase the concentration of hydroxide ions (OH-) and decrease the concentration of hydrogen ions (H+), making the solution more basic.

Cytokinesis is the stage of the cell cycle where the cytoplasm of the cell divides, resulting in the formation of two daughter cells. In this stage, the nuclear material has already been divided during the previous stage, called telophase. The image or context of the question may not be available, but based on the given options, cytokinesis is the stage that specifically involves the division of the cytoplasm, which is the correct answer.

When atoms in molecules form a covalent bond, they share pairs of electrons. This type of bond occurs when atoms have similar electronegativities and are able to share electrons to achieve a stable electron configuration. In a covalent bond, the shared electrons are attracted to both nuclei, creating a strong bond between the atoms. Ionic bonds involve the transfer of electrons, hydrogen bonds are weaker interactions between molecules, and polymers are large molecules composed of repeating subunits.

Totipotent stem cells have the ability to differentiate into any type of cell in the body, including both embryonic and extraembryonic cells. This means that they can give rise to all cell types in an organism, including the cells of the placenta and other supporting tissues. Totipotent stem cells are the earliest stage of development and are found in the fertilized egg or zygote. They have the highest level of potency and are capable of generating a complete organism.

Adhesion refers to the attraction between different substances. It is the ability of different substances to stick or cling to each other. This phenomenon occurs due to the intermolecular forces between molecules of different substances. Adhesion is commonly observed when water molecules adhere to the surface of a solid, such as when water sticks to the sides of a glass or when a raindrop sticks to a leaf.

During prophase, the nuclear membrane breaks down, allowing the chromosomes to become visible. This is an important step in cell division as it allows the chromosomes to be properly organized and prepared for separation. The breakdown of the nuclear membrane also allows for the movement of other cellular components during cell division. Therefore, the characteristic of prophase mentioned in the answer is accurate.

Mitosis is the process of cell division, where a single cell divides into two identical daughter cells. During mitosis, the nucleus of the cell also divides, ensuring that each daughter cell receives a complete set of genetic material. Therefore, the term "mitosis" refers to the division of the nucleus, not the division of the entire cell or the cytoplasm. The replication of DNA occurs before mitosis, during the S phase of the cell cycle.

The rough endoplasmic reticulum is responsible for making membranes and proteins. It contains ribosomes on its surface, which are responsible for protein synthesis. The rough endoplasmic reticulum plays a crucial role in the production, folding, and modification of proteins. Additionally, it is involved in the synthesis of lipids and the transport of proteins to other parts of the cell or to the cell membrane. The smooth endoplasmic reticulum, Golgi apparatus, and chloroplasts have other functions within the cell and are not primarily responsible for making membranes and proteins.

Centrioles are cylindrical structures found only in animal cells. They play a crucial role in cell division by organizing the microtubules that form the spindle apparatus. This helps in the separation of chromosomes during cell division. Plant cells do not contain centrioles, making it a feature exclusive to animal cells. The other options, such as central vacuole, mitochondria, and nucleus, are found in both animal and plant cells.

G2 phase is the third phase of the cell cycle, following the S phase where DNA is replicated. During G2 phase, the cell continues to grow and prepares for mitosis, which is the process of cell division. This includes synthesizing the necessary proteins and organelles for cell division, as well as checking for any errors in DNA replication. Therefore, the characteristic of G2 phase is cell growth and preparation for mitosis.

The ability of a normal cell to express only certain genes allows it to differentiate and specialize. This means that the cell can develop into a specific type of cell with a specific function. Through gene expression, different cells in the body can acquire different characteristics and perform different tasks, leading to the specialization of cells in various tissues and organs. This differentiation is crucial for the proper functioning of the body and the maintenance of homeostasis.

If an organic molecule model contains carbon atoms arranged in a long chain, it is probably a model of a lipid. Lipids are organic molecules that are characterized by long chains of carbon atoms bonded together. They are an important component of cell membranes and serve as a source of energy in the body.

Telophase is the final stage of mitosis where the nuclear membrane reforms around the separated chromosomes. During this stage, the chromosomes reach the opposite poles of the cell, and a new nuclear envelope starts to form around each set of chromosomes. This reformation of the nuclear membrane marks the completion of cell division and the beginning of cytokinesis, where the cytoplasm divides into two daughter cells. Cell growth and preparation for mitosis occur in earlier stages of the cell cycle, while DNA replication takes place during the S phase of interphase.

Stem cells are important to multicellular organisms because of their capacity to differentiate. This means that they have the ability to develop into different types of cells with specific functions, such as muscle cells, nerve cells, or blood cells. This differentiation process is crucial for the growth, development, and repair of tissues and organs in the body. Without the capacity to differentiate, stem cells would not be able to fulfill their role in maintaining and regenerating the various cell types needed for the proper functioning of the organism.