Biological Molecules Quiz Questions
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Using its antennae, the male moth finds female moths by following a trail of airborne chemicals, called pheromones, upwind from the female producing them. This is an example of...
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Reproduction
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Response to stimuli
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Grow
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Acquire nutrients
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Homeostasis
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This quiz explores fundamental concepts in biology and chemistry, focusing on molecular structures, chemical bonding, biological responses, organism traits, atomic structure, and homeostasis. It assesses understanding of how biological molecules function in various processes.
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- 2.
After you drink acidic lemonade, your body stays at the same pH. This is an example of...
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Maintaining homeostasis
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Growth
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Evolve in response to environment
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Behavior
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Maintain cellular organization
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Immunization to weak acids
Correct Answer
A. Maintaining homeostasisExplanation
The fact that your body stays at the same pH after drinking acidic lemonade suggests that it is maintaining homeostasis. Homeostasis refers to the body's ability to regulate and maintain a stable internal environment despite external changes. In this case, your body is able to balance the pH levels and keep it within a normal range, even after consuming an acidic substance like lemonade. This is an example of the body's ability to maintain homeostasis.Rate this question:
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- 3.
If an atom has a charge of +1 that means...
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It has 1 more neutron than protons and electron
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It has 1 more proton than electrons
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It has 1 more electron than protons
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It has same number of protons and electrons
Correct Answer
A. It has 1 more proton than electronsExplanation
If an atom has a charge of +1, it means that it has lost one electron. Since electrons have a negative charge, losing one electron would result in a net positive charge for the atom. Therefore, the atom would have one more proton than electrons, as protons have a positive charge.Rate this question:
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- 4.
Phosphorous has an atomic number of 15, in the first shell it has ________ electrons, second shell has ________ electrons, and third shell has ________ electrons.
Correct Answer
2, two
8, eight
5, fiveExplanation
Phosphorous has an atomic number of 15, which means it has 15 protons and 15 electrons. The electrons are distributed in different shells around the nucleus. The first shell can hold a maximum of 2 electrons, so it has 2 electrons. The second shell can hold a maximum of 8 electrons, so it has 8 electrons. The remaining 5 electrons are in the third shell. Therefore, the correct answer is 2, two, 8, eight, 5, five.Rate this question:
- 5.
Most biological bonds in the body are..
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Covalent
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Ionic
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Hydrogen
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Peptide
Correct Answer
A. CovalentExplanation
Most biological bonds in the body are covalent. Covalent bonds involve the sharing of electrons between atoms, resulting in a strong bond. In biological molecules such as proteins, nucleic acids, and carbohydrates, covalent bonds are essential for maintaining the structure and function of these molecules. These bonds are formed through the sharing of electrons in the outermost energy levels of atoms, creating stable and durable connections. Covalent bonds are crucial for the stability and integrity of biological systems, allowing for the formation of complex structures and the transmission of genetic information.Rate this question:
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- 6.
What does H-O-H represent?
Correct Answer
molecule of water, waterExplanation
H-O-H represents the chemical formula of water, which consists of two hydrogen atoms bonded to one oxygen atom. This arrangement forms a molecule of water, commonly known as water.Rate this question:
- 7.
The smallest units that still retain the characteristics of an element are called
Correct Answer
atoms, atomExplanation
Atoms are the smallest units that retain the properties and characteristics of an element. They are the building blocks of matter and cannot be broken down into smaller particles without losing their elemental properties. Each atom consists of a nucleus containing protons and neutrons, surrounded by electrons in energy levels. Atoms combine to form molecules and compounds, and their unique arrangements and interactions determine the properties and behavior of different substances. Therefore, atoms are the correct answer for the question.Rate this question:
- 8.
Which of the following is true of carbon?
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It can form polar and nonpolar bonds.
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It only forms polar molecules.
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It is highly electronegative.
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It can form a maximum of three covalent bonds with other elements.
Correct Answer
A. It can form polar and nonpolar bonds.Explanation
Carbon is a versatile element that can form both polar and nonpolar bonds. This is because carbon has four valence electrons, allowing it to form up to four covalent bonds with other elements. Depending on the atoms it bonds with and the arrangement of these bonds, carbon can form both polar and nonpolar molecules. The ability of carbon to form a variety of bonds is the basis for the vast diversity of organic compounds found in nature.Rate this question:
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- 9.
For an atom to achieve maximum stability and become chemically inert, what must occur?
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Electron pairs are shared.
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Its outermost energy shell must be filled with electrons.
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The number of electrons must equal the number of protons.
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Ionization occurs.
Correct Answer
A. Its outermost energy shell must be filled with electrons.Explanation
In order for an atom to achieve maximum stability and become chemically inert, its outermost energy shell must be filled with electrons. This is because the outermost energy shell, also known as the valence shell, determines the atom's reactivity. When the valence shell is completely filled with electrons, the atom is stable and less likely to react with other atoms. This stability is achieved by either gaining, losing, or sharing electrons with other atoms to fill the valence shell.Rate this question:
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- 10.
Which of the following statements is true for the class of biological molecules known as lipids?
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They are insoluble in water.
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They are soluble in water.
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They contain nitrogen.
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They are made of amino acids.
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They are made from glycerol, fatty acids, and phosphate
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They contain less energy than proteins and carbohydrates.
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They are made by dehydration reactions
Correct Answer
A. They are insoluble in water.Explanation
Lipids are a class of biological molecules that are insoluble in water. This is because they are hydrophobic, meaning they repel water molecules. Lipids have a nonpolar structure, which prevents them from forming hydrogen bonds with water molecules. Instead, lipids tend to aggregate together, forming structures such as cell membranes or fat droplets. Lipids play important roles in energy storage, insulation, and cell signaling.Rate this question:
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- 11.
Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?
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Starch
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Disaccharide
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Pentose
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Polysaccharide
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Monosaccharide
Correct Answer
A. DisaccharideExplanation
Lactose is classified as a disaccharide because it is composed of two sugar molecules, glucose and galactose, joined together by a glycosidic linkage. A disaccharide is a type of carbohydrate that consists of two monosaccharide units. Starch, pentose, and polysaccharide are not correct classifications for lactose because they refer to different types of carbohydrates. Monosaccharide is also not the correct classification because lactose is made up of two sugar molecules, not one.Rate this question:
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- 12.
The tertiary structure of a protein is the
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Order in which amino acids are joined in a polypeptide chain.
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Overall protein structure resulting from the aggregation of two or more polypeptide subunits.
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Unique three-dimensional shape of the fully folded polypeptide.
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Bonding together of several polypeptide chains by weak bonds.
Correct Answer
A. Unique three-dimensional shape of the fully folded polypeptide.Explanation
The tertiary structure of a protein refers to the unique three-dimensional shape that the fully folded polypeptide adopts. This structure is determined by the interactions between the amino acid side chains and the surrounding environment, including hydrogen bonds, disulfide bonds, hydrophobic interactions, and electrostatic interactions. The specific arrangement of these interactions gives the protein its characteristic shape, which is essential for its proper function.Rate this question:
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- 13.
Which of the following statements concerning saturated fats is not true?
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They are one of several factors that contribute to heart disease.
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They contain more hydrogen than unsaturated fats having the same number of carbon atoms.
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They generally solidify at room temperature.
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They have multiple double bonds in the carbon chains of their fatty acids.
Correct Answer
A. They have multiple double bonds in the carbon chains of their fatty acids.Explanation
Saturated fats are known to contribute to heart disease, contain more hydrogen than unsaturated fats with the same number of carbon atoms, and generally solidify at room temperature. However, they do not have multiple double bonds in the carbon chains of their fatty acids. Instead, saturated fats have single bonds between all carbon atoms, which is why they are "saturated" with hydrogen atoms. This lack of double bonds makes them less prone to oxidation and more stable.Rate this question:
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- 14.
Which bonds are created during the formation of the primary structure of a protein?
Correct Answer
peptide bonds, peptideExplanation
During the formation of the primary structure of a protein, peptide bonds are created. Peptide bonds are formed by a condensation reaction between the carboxyl group of one amino acid and the amino group of another amino acid. These bonds link the amino acids together in a linear chain, forming the backbone of the protein. The resulting chain of amino acids is called a peptide. Therefore, the correct answer is peptide bonds and peptide.Rate this question:
- 15.
If 14C-labeled uracil is added to the growth medium of cells, what macromolecules will be labeled?
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DNA
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Both DNA and RNA
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RNA
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Proteins
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Phospholipids
Correct Answer
A. RNAExplanation
When 14C-labeled uracil is added to the growth medium of cells, the macromolecules that will be labeled are RNA. This is because uracil is a component of RNA, specifically in the form of ribonucleotides. DNA, on the other hand, does not contain uracil but instead contains thymine. Therefore, only RNA molecules will incorporate the labeled uracil and become labeled themselves.Rate this question:
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- 16.
The control group is the group without the changed variable and it forms baseline for comparisons.
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True
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False
Correct Answer
A. TrueExplanation
Experimental: group with the changed variable
Control: group without the changed variable, forms baseline for comparisons.Rate this question:
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- 17.
Atoms with unequal # of protons and electrons
Correct Answer
ion, ionsExplanation
Atoms with unequal numbers of protons and electrons are called ions. When an atom gains or loses electrons, it becomes electrically charged. If an atom gains electrons, it becomes negatively charged and is called an anion. On the other hand, if an atom loses electrons, it becomes positively charged and is called a cation. These charged atoms are referred to as ions.Rate this question:
- 18.
Chemical processes that occur within a living organism in order to maintain life
Correct Answer
metabolismExplanation
Metabolism refers to the chemical processes that take place within a living organism to maintain life. It involves the conversion of food into energy, the synthesis of molecules necessary for growth and repair, and the breakdown of waste products. Metabolism is essential for various biological functions such as digestion, respiration, and circulation. It allows organisms to obtain energy from nutrients and regulate their internal environment. Overall, metabolism is a vital process that sustains life by ensuring the proper functioning of cells and tissues.Rate this question:
- 19.
What makes fat hydrophobic?
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The fatty acid tail is nonpolar
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The fatty acid tail is polar
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Because of the nitrogen present
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Because of the oxygen present
Correct Answer
A. The fatty acid tail is nonpolarExplanation
The correct answer is that the fatty acid tail is nonpolar. This means that it does not have a charge and does not interact well with water molecules, which are polar. Hydrophobic substances, like fats, repel water because their nonpolar nature prevents them from forming favorable interactions with polar molecules.Rate this question:
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- 20.
Which is a type of steroid?
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Cholesterol
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Sugar
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Galactose
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Adenine
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Thymine
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Glycerine
Correct Answer
A. CholesterolExplanation
Cholesterol is a type of steroid. Steroids are a class of organic compounds that have a characteristic structure of four fused rings. Cholesterol is a sterol, which is a subgroup of steroids that have a hydroxyl group at the 3-position. It is an essential component of cell membranes and is also involved in the production of hormones, vitamin D, and bile acids. Cholesterol is mainly synthesized in the liver and is also obtained from dietary sources. High levels of cholesterol in the blood can increase the risk of heart disease.Rate this question:
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- 21.
Which of the following are disaccharides?
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Sucrose
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Lactose
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Maltose
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Starch
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Glucose
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Galactose
Correct Answer(s)
A. Sucrose
A. Lactose
A. MaltoseExplanation
Sucrose, lactose, and maltose are all examples of disaccharides. Disaccharides are carbohydrates composed of two monosaccharide units joined together by a glycosidic bond. Sucrose is made up of glucose and fructose, lactose is made up of glucose and galactose, and maltose is made up of two glucose molecules. Starch, glucose, and galactose are not disaccharides. Starch is a polysaccharide made up of many glucose units, while glucose and galactose are monosaccharides, which are single sugar units.Rate this question:
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- 22.
What determines a protein's function?
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Its shape
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The nucleotides
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The ribosomes
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Its polarity
Correct Answer
A. Its shapeExplanation
The shape of a protein determines its function. Proteins are made up of long chains of amino acids that fold into specific shapes. These shapes are crucial for the protein to interact with other molecules and perform its specific function in the body. Different shapes allow proteins to bind to specific targets, catalyze reactions, transport molecules, and carry out various cellular processes. Therefore, the shape of a protein is a critical factor in determining its function.Rate this question:
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- 23.
What is released every time amino acids bond?
Correct Answer
water, H2O, h2oExplanation
When amino acids bond, a process called dehydration synthesis occurs, where a water molecule is released. This happens because one amino acid donates a hydrogen atom (H) and the other donates a hydroxyl group (OH), resulting in the formation of a covalent bond between the two amino acids. The hydrogen atom and hydroxyl group combine to form a water molecule (H2O), which is released as a byproduct of the bonding process.Rate this question:
- 24.
Characteristics of RNA:
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Ribose sugar
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Adenine
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Uracil
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Cytosine
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Thymine
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Guanine
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Has one more oxygen (hydroxyl group)
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Single strands
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Double strands
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Has one less oxygen (hydroxyl group)
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Deoxyribose sugar
Correct Answer(s)
A. Ribose sugar
A. Adenine
A. Uracil
A. Cytosine
A. Guanine
A. Has one more oxygen (hydroxyl group)
A. Single strandsExplanation
RNA is a type of nucleic acid that contains ribose sugar, which is one of its characteristic features. It also consists of the nitrogenous bases adenine, uracil, cytosine, and guanine. Unlike DNA, RNA has one more oxygen (hydroxyl group) attached to its ribose sugar, giving it a slightly different structure. Another characteristic of RNA is that it typically exists as single strands, whereas DNA can form double strands. Therefore, the given answer correctly identifies the characteristics of RNA.Rate this question:
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- 25.
DNA Strand: Single Strand DNA sequence = AGCTAACTGGDNA complementary strand = ________mRNA strand = ________
Correct Answer(s)
TCGATTGACC
UCGAUUGACCExplanation
The given DNA strand is AGCTAACTGG. To find the complementary strand, we need to replace each nucleotide with its complementary base. A pairs with T, G pairs with C, C pairs with G, and T pairs with A. Therefore, the complementary strand is TCGATTGACC. To find the mRNA strand, we need to replace each T with U. So, the mRNA strand is UCGAUUGACC.Rate this question:
- 26.
Biggest difference between prokaryotic cells and eukaryotic cells
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Membrane bound organelles
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Plasma membrane
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Selective permeability
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Containing DNA
Correct Answer
A. Membrane bound organellesExplanation
The biggest difference between prokaryotic cells and eukaryotic cells is the presence of membrane-bound organelles. Prokaryotic cells lack membrane-bound organelles, while eukaryotic cells have various membrane-bound organelles such as mitochondria, endoplasmic reticulum, and Golgi apparatus. These organelles perform specific functions within the cell, allowing for compartmentalization and specialization of cellular processes. This distinction in cellular organization is a fundamental characteristic that sets prokaryotic and eukaryotic cells apart.Rate this question:
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- 27.
The function of the endomembrane system?
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Regulates protein traffic and performs metabolic functions in the cell.
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Powerhouse of the cell
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Stores DNA
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Stores water
Correct Answer
A. Regulates protein traffic and performs metabolic functions in the cell.Explanation
The endomembrane system in a cell is responsible for regulating protein traffic and performing metabolic functions. It consists of various organelles such as the endoplasmic reticulum, Golgi apparatus, lysosomes, and vesicles. These organelles work together to synthesize, modify, package, and transport proteins within the cell. They also play a role in lipid metabolism, detoxification, and calcium storage. Therefore, the correct answer is that the endomembrane system regulates protein traffic and performs metabolic functions in the cell.Rate this question:
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- 28.
Simple carbohydrates are the main source of immediate ________.
Correct Answer
energyExplanation
Simple carbohydrates (sugar, glucose, fructose etc) are the main source of immediate energy. That is, they are metabolized easily and quickly. All our cells can use glucose for energy, so once it is metabolized and reaches the blood stream it can travel to other cells and tissues.Rate this question:
- 29.
Fatty acids are formed by dehydration reactions.
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True
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False
Correct Answer
A. FalseExplanation
Fatty acids are not formed by dehydration reactions. Dehydration reactions involve the removal of water molecules to form larger molecules. Fatty acids, on the other hand, are typically formed through the process of hydrolysis, which involves the addition of water molecules to break down larger molecules into smaller ones. Therefore, the statement that fatty acids are formed by dehydration reactions is false.Rate this question:
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- 30.
How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long?
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10
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5
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6
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11
Correct Answer
A. 10Explanation
To completely hydrolyze a polymer that is 11 monomers long, each monomer needs to be broken down by a water molecule. Since there are 11 monomers, we need 11 water molecules to fully hydrolyze the polymer. Therefore, the correct answer is 11.Rate this question:
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- 31.
Which polymer contains nitrogen?
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Chitin
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Cellulose
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Starch
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Glycogen
Correct Answer
A. ChitinExplanation
Chitin is the correct answer because it is a polymer that contains nitrogen. Chitin is a structural polysaccharide found in the exoskeletons of arthropods and the cell walls of fungi. It is composed of repeating units of N-acetylglucosamine, which contains nitrogen. Cellulose, starch, and glycogen are all polysaccharides but do not contain nitrogen.Rate this question:
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- 32.
What maintains the secondary structure of a protein?
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Hydrogen bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond
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Covalent bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond
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Ionic bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond
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Peptide bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond
Correct Answer
A. Hydrogen bonds between the amino group of one peptide bond and the carboxyl group of another peptide bondExplanation
Hydrogen bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond maintain the secondary structure of a protein. These hydrogen bonds form between the peptide backbone atoms, specifically between the nitrogen atom of one amino acid and the oxygen atom of another amino acid. These bonds stabilize the folding of the protein into secondary structures such as alpha helices and beta sheets. Covalent bonds and ionic bonds do not play a significant role in maintaining the secondary structure, while peptide bonds are responsible for connecting amino acids in the primary structure of a protein.Rate this question:
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- 33.
Of the following is true of both starch and cellulose?
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They are both polymers of glucose.
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They are cis-trans isomers of each other.
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They can both be digested by humans.
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They are both used for energy storage in plants.
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They are both structural components of the plant cell wall.
Correct Answer
A. They are both polymers of glucose.Explanation
Both starch and cellulose are polymers of glucose. Starch is a polysaccharide composed of glucose units and serves as a storage form of energy in plants. It is easily digested by humans. Cellulose, on the other hand, is also a polysaccharide made up of glucose units but has a different arrangement, making it indigestible for humans. Cellulose functions as a structural component of the plant cell wall, providing rigidity and support.Rate this question:
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- 34.
Humans can digest starch but not cellulose because
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The monomer of starch is glucose, while the monomer of cellulose is galactose.
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Humans have enzymes that can hydrolyze the β glycosidic linkages of starch but not the α glycosidic linkages of cellulose.
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Humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.
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humans harbor starch-digesting bacteria in the digestive tract.
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The monomer of starch is glucose, while the monomer of cellulose is glucose with a nitrogen-containing group.
Correct Answer
A. Humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.Explanation
The correct answer is that humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose. This is because the enzymes in our digestive system, such as amylase, are specifically designed to break down the α glycosidic linkages found in starch. However, we lack the enzymes necessary to break down the β glycosidic linkages in cellulose. Therefore, while we can digest starch and obtain energy from it, we cannot digest cellulose and it passes through our digestive system as dietary fiber.Rate this question:
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- 35.
Which type of interaction stabilizes the α helix and the β pleated sheet structures of proteins?
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Hydrogen bonds
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Ionic bonds
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Peptide bonds
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Covalent bonds
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Disulfide bonds
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Hydrophobic interactions
Correct Answer
A. Hydrogen bondsExplanation
Hydrogen bonds are responsible for stabilizing the α helix and β pleated sheet structures of proteins. These bonds occur between the hydrogen atom of one amino acid and the oxygen or nitrogen atom of another amino acid. The hydrogen bond is a relatively weak bond, but when many hydrogen bonds are present in a protein structure, they collectively provide stability and help maintain the secondary structure of the protein.Rate this question:
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- 36.
Misfolding of polypeptides is a serious problem in cells. Which of the following diseases are associated with an accumulation of misfolded polypeptides?
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Alzheimer's and Parkinson's only
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Parkinson's
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Alzheimer's
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Alzheimer's, Parkinson's, and diabetes mellitus
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Diabetes mellitus only
Correct Answer
A. Alzheimer's and Parkinson's onlyExplanation
Alzheimer's and Parkinson's diseases are both neurodegenerative disorders characterized by the accumulation of misfolded proteins in the brain. In Alzheimer's disease, beta-amyloid plaques and tau tangles form due to the misfolding of amyloid beta and tau proteins, respectively. In Parkinson's disease, misfolded alpha-synuclein protein aggregates form Lewy bodies, which are found in neurons. Diabetes mellitus is not directly associated with the accumulation of misfolded polypeptides.Rate this question:
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- 37.
One of the primary functions of RNA molecules is to
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Function in the synthesis of proteins.
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Transmit genetic information to offspring.
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Make a copy of itself, thus ensuring genetic continuity.
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Act as a pattern or blueprint to form DNA.
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Form the genes of higher organisms.
Correct Answer
A. Function in the synthesis of proteins.Explanation
RNA molecules play a crucial role in protein synthesis. They act as messengers, carrying the genetic information from DNA to the ribosomes, where proteins are synthesized. RNA molecules are transcribed from DNA and then translated into proteins. This process is known as gene expression. Therefore, one of the primary functions of RNA molecules is to function in the synthesis of proteins.Rate this question:
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- 38.
Which of the following is an example of hydrolysis?
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The reaction of two monosaccharides, forming a disaccharide with the release of water
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The synthesis of two amino acids, forming a peptide with the release of water
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The reaction of a fat, forming glycerol and fatty acids with the release of water
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The reaction of a fat, forming glycerol and fatty acids with the consumption of water
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The synthesis of a nucleotide from a phosphate, a pentose sugar, and a nitrogenous base with the production of a molecule of water
Correct Answer
A. The reaction of a fat, forming glycerol and fatty acids with the consumption of water -
- 39.
What is this?
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Saturated fatty acid
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Unsaturated fatty acid
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Protein
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Amino acid
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Carbohydrate
Correct Answer
A. Saturated fatty acidExplanation
A saturated fatty acid is a type of fat molecule that contains only single bonds between carbon atoms and is saturated with hydrogen atoms. This means that all carbon atoms in the fatty acid chain are bonded to the maximum number of hydrogen atoms possible. Saturated fatty acids are typically solid at room temperature and are commonly found in animal products such as meat and dairy. They are known to contribute to an increased risk of heart disease when consumed in excess.Rate this question:
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- 40.
A substance with specific properties that can not be broken down or converted to another substance is a(n):
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Element
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Compound
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Molecule
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Protein
Correct Answer
A. ElementExplanation
An element is a substance with specific properties that cannot be broken down or converted into another substance. Elements are made up of only one type of atom and cannot be further simplified. Unlike compounds, which are made up of two or more different elements, elements exist on their own. Molecules, on the other hand, can be made up of either one element or multiple elements. Proteins, while they are made up of atoms, are not considered elements as they can be broken down into smaller components called amino acids.Rate this question:
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- 41.
The type of bonds present in a molecule determine its properties. Which type of bond is associated with molecules that are soluble in water (i.e., molecules that do not precipitate)
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Strong ionic bond
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Polar covalent bond
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Nonpolar covalent bond
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Hydrophobic interaction (force between hydrophobic molecules that causes oil to separate from vinegar solutions)
Correct Answer
A. Polar covalent bondExplanation
Polar covalent bonds are associated with molecules that are soluble in water. In a polar covalent bond, electrons are shared unequally between atoms, creating partial positive and negative charges. Water is a polar molecule, with a slightly positive hydrogen end and a slightly negative oxygen end. When a molecule with polar covalent bonds comes into contact with water, the positive end of water attracts the negative end of the molecule and vice versa. This allows the molecule to dissolve in water, making it soluble and preventing it from precipitating.Rate this question:
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- 42.
What do you call elements with the same number of protons but different atomic masses?
Correct Answer
isotope, isotopes, an isotopeExplanation
Isotopes are elements that have the same number of protons but differ in their atomic masses. This is because isotopes have different numbers of neutrons in their nuclei. The variation in the number of neutrons results in different atomic masses for the same element. Isotopes can have slightly different physical and chemical properties due to the variation in atomic mass, but they still belong to the same element because they have the same number of protons.Rate this question:
- 43.
What is the chemical reaction mechanism by which cells make polymers from monomers?
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The formation of disulfide bridges between monomer
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Phosphodiester linkages
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Ionic bonding of monomers
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Dehydration reactions
Correct Answer
A. Dehydration reactionsExplanation
Dehydration reactions involve the removal of water molecules from monomers, allowing them to form covalent bonds and create polymers. This process is commonly seen in the synthesis of biological macromolecules such as proteins, nucleic acids, and carbohydrates. By eliminating water, cells can link monomers together and form larger, more complex structures necessary for various cellular functions.Rate this question:
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- 44.
Which level of protein structure do the α helix and the β pleated sheet represent?
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Secondary
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Primary
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Quarternary
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Tertiary
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All of the above
Correct Answer
A. SecondaryExplanation
The α helix and β pleated sheet represent the secondary level of protein structure. Secondary structure refers to the local folding patterns of the polypeptide chain, specifically the regular repeating structures formed by hydrogen bonding between the amino acid residues. The α helix is a coiled structure, while the β pleated sheet consists of strands of the polypeptide chain lying side by side, forming a sheet-like structure. The primary structure refers to the linear sequence of amino acids, while the tertiary and quaternary structures involve the overall 3D folding and interactions between multiple polypeptide chains, respectively.Rate this question:
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- 45.
Which of the following is not a monomer/polymer pairing?
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Triglyceride/phospholipid bilayer
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Deoxyribonucleotide/DNA
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Amino acid/protein
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Ribonucleotide/RNA
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Monosaccharide/polysaccharide
Correct Answer
A. Triglyceride/phospholipid bilayerExplanation
The correct answer is triglyceride/phospholipid bilayer. Triglyceride is a type of lipid composed of three fatty acids and glycerol, while a phospholipid bilayer is a type of lipid that forms the cell membrane. Although both triglycerides and phospholipids are lipids, they have different structures and functions. Triglycerides are used for energy storage, while phospholipids are essential for cell structure and function. Therefore, triglyceride/phospholipid bilayer is not a monomer/polymer pairing.Rate this question:
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- 46.
All of the following are TRUE about living organisms EXCEPT...
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Reproduce themselves
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Grow into multicellular organisms
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Have an active metabolism
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Are made of cells
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Respond to stimuli
Correct Answer
A. Grow into multicellular organismsExplanation
Living organisms can grow into multicellular organisms, so this statement is not true. All living organisms have the ability to reproduce, have an active metabolism, are made of cells, and respond to stimuli. However, not all living organisms grow into multicellular organisms. Some organisms, such as bacteria and single-celled protists, remain as single cells throughout their life cycle. Therefore, the statement "grow into multicellular organisms" is not true for all living organisms.Rate this question:
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- 47.
The element present in all organic molecules is
Correct Answer
CarbonExplanation
Carbon is the element that is present in all organic molecules. This is because carbon has the unique ability to form covalent bonds with other carbon atoms and a variety of other elements, allowing for the formation of complex and diverse organic compounds. Organic molecules are defined as compounds that contain carbon atoms bonded to hydrogen atoms, along with other elements such as oxygen, nitrogen, and sulfur. Therefore, carbon is the fundamental element in organic chemistry and is essential for the existence of life as we know it.Rate this question:
- 48.
The structural formula for a certain molecule includes a group symbolized -O. The dash next to the oxygen atom means that a single bond exists to another atom, such as a carbon. Based on the valence of oxygen and the number of bonds it normally forms, what is the charge on the oxygen atom in this case?
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-2
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-1
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+1
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+2
Correct Answer
A. -1Explanation
The dash next to the oxygen atom indicates that it is bonded to another atom, such as carbon, through a single bond. Oxygen typically forms two bonds, so in this case, it has one bond remaining. Since oxygen has six valence electrons, and it needs eight to have a full octet, it will gain one electron to achieve stability. Gaining an electron results in a negative charge, so the charge on the oxygen atom in this case is -1.Rate this question:
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- 49.
When the atoms involved in a covalent bond have the same electronegativity, what type of bond results?
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Ionic bond
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Polar covalent bond
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Nonpolar covalent bond
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Hydrogen bond
Correct Answer
A. Nonpolar covalent bondExplanation
When the atoms involved in a covalent bond have the same electronegativity, it means that they have an equal pull for the shared electrons. This results in a nonpolar covalent bond, where the electrons are shared equally between the atoms. In this type of bond, there is no separation of charge and the molecule is symmetrical.Rate this question:
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Jan 23, 2023Quiz Edited by
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Apr 16, 2016Quiz Created by
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