A.P. Biology Chapter 5 (Macromolecules)
In this quiz which focuses on the scientific topic of biology, we’ll be taking a specific look at macromolecules – which are very large molecules commonly created by the polymerization of smaller subunits. An example of these macromolecules is protein, which is a biopolymer and shares the category with nucleic acids, carbohydrates and lipids. What else do you know about macromolecules? Take the quiz and we’ll find out!
Questions and Answers
- 1.
What is a monomer?
- A.
A single unit of macromolecules
- B.
Multiple units of macromolecules
- C.
A type of protein
- D.
An organic compound
Correct Answer
A. A single unit of macromoleculesExplanation
A monomer refers to a single unit of macromolecules. Macromolecules, such as proteins, nucleic acids, and carbohydrates, are composed of repeating units called monomers. These monomers join together through chemical bonds to form larger, more complex structures. Therefore, the correct answer is "A single unit of macromolecules."Rate this question:
-
- 2.
What is a polymer?
- A.
A single unit of macromolecules
- B.
Multiple units of macromolecules
- C.
A type of protein
- D.
An organic compound
Correct Answer
B. Multiple units of macromoleculesExplanation
A polymer is a large molecule made up of repeating subunits called monomers. These monomers join together to form a long chain, resulting in a macromolecule. Therefore, the correct answer is "Multiple units of macromolecules."Rate this question:
-
- 3.
How do you get from a monomer to a polymer?
- A.
Add water
- B.
Add carbon
- C.
Remove water
- D.
Remove carbon
Correct Answer
C. Remove waterExplanation
To form a polymer from a monomer, the process of dehydration synthesis is used. This involves removing a water molecule from between two monomers, which forms a covalent bond between them. This reaction allows the monomers to join together and create a larger molecule, known as a polymer. Therefore, the correct answer is "Remove water."Rate this question:
-
- 4.
How do you get from a polymer to a monomer?
- A.
Add water
- B.
Add carbon
- C.
Remove water
- D.
Remove carbon
Correct Answer
A. Add waterExplanation
When water is added to a polymer, it undergoes a process called hydrolysis. During hydrolysis, water molecules break the bonds between the monomers in the polymer chain, resulting in the formation of individual monomer units. This process is commonly used in the digestion of complex carbohydrates in our bodies, where enzymes break down polymers like starch into monosaccharides by adding water molecules. Therefore, adding water to a polymer is the correct way to break it down into its monomer units.Rate this question:
-
- 5.
What is a dehydration/condensation reaction?
- A.
The addition of water
- B.
The removal of water
- C.
How to get from a polymer to a monomer
- D.
How to get from a monomer to a polymer
- E.
A and C
- F.
B and D
Correct Answer
F. B and DExplanation
A dehydration/condensation reaction refers to the process of removing water molecules from a substance. In the context of polymers and monomers, it is the mechanism by which monomers combine to form polymers. This reaction involves the removal of a water molecule as a byproduct, resulting in the formation of a covalent bond between the monomers. Therefore, options B and D, which state "The removal of water" and "How to get from a monomer to a polymer," respectively, correctly describe a dehydration/condensation reaction.Rate this question:
-
- 6.
What is hydrolysis?
- A.
The addition of water
- B.
The removal of water
- C.
How to get from a polymer to a monomer
- D.
How to get from a monomer to a polymer
- E.
A and C
- F.
B and D
Correct Answer
E. A and CExplanation
Hydrolysis refers to the chemical reaction that involves the addition of water to break down a compound into its smaller components. In the context of polymers, hydrolysis is the process of breaking down a polymer into its monomer units by adding water. Therefore, options A and C, which state that hydrolysis is the addition of water and how to get from a polymer to a monomer, respectively, are both correct explanations for hydrolysis.Rate this question:
-
- 7.
What are carbohydrates?
- A.
Proteins
- B.
Fats, oils, etc..
- C.
Sugars, starches, etc..
- D.
The basis of genetics
Correct Answer
C. Sugars, starches, etc..Explanation
Carbohydrates are organic compounds that consist of sugars, starches, and fibers. They are one of the three macronutrients required by the body for energy production. Carbohydrates can be found in various foods such as grains, fruits, vegetables, and dairy products. They provide the body with a quick source of energy and play a crucial role in maintaining proper brain function. Additionally, carbohydrates are important for digestion and are essential for the synthesis of certain molecules in the body.Rate this question:
-
- 8.
What is the ratio of carbohydrate chemical formulas?
- A.
CHO3O
- B.
CH2O
- C.
CHO
- D.
CHO2
Correct Answer
B. CH2OExplanation
The correct answer is CH2O. This is because the ratio of carbohydrate chemical formulas is typically represented as CH2O, meaning that for every carbon atom, there are two hydrogen atoms and one oxygen atom. This ratio is consistent across most carbohydrates.Rate this question:
-
- 9.
How many calories are in 1g of carbohydrate?
- A.
1
- B.
4
- C.
9
- D.
15
Correct Answer
B. 4Explanation
Carbohydrates provide 4 calories per gram. This means that for every gram of carbohydrate consumed, the body receives 4 calories of energy. This is because carbohydrates are a macronutrient that the body breaks down and converts into glucose, which is then used as fuel for various bodily functions. Therefore, the correct answer is 4.Rate this question:
-
- 10.
What is the monomer of carbs?
- A.
Nucleotide
- B.
Amino Acid
- C.
Monosaccharide
- D.
Glycerol
Correct Answer
C. MonosaccharideExplanation
The monomer of carbs is a monosaccharide. Carbohydrates are made up of repeating units of monosaccharides, which are simple sugars such as glucose, fructose, and galactose. These monosaccharides can be joined together through glycosidic bonds to form larger carbohydrates like disaccharides (e.g. sucrose, lactose) and polysaccharides (e.g. starch, cellulose). Therefore, monosaccharides are the building blocks or monomers of carbohydrates.Rate this question:
-
- 11.
What are the 3 monosaccharides?
- A.
Glucose, Sucrose, Lactose
- B.
Maltose, Fructose, Galactose
- C.
Glucose, Fructose, Galactose
- D.
Maltose, Sucrose, Lactose
Correct Answer
C. Glucose, Fructose, GalactoseExplanation
The correct answer is glucose, fructose, and galactose. Monosaccharides are the simplest form of carbohydrates and cannot be broken down further. Glucose is the primary source of energy for the body, fructose is commonly found in fruits and is the sweetest of the three, and galactose is found in dairy products.Rate this question:
-
- 12.
What is the polymer of a carbohydrate?
- A.
Phospholipid
- B.
Disaccharide
- C.
DNA
- D.
Secondary Structure
Correct Answer
B. DisaccharideExplanation
A disaccharide is a type of carbohydrate made up of two monosaccharide units joined together through a glycosidic bond. It is considered a polymer of a carbohydrate because it is composed of repeating units (monosaccharides) linked together. Other options like phospholipid, DNA, and secondary structure are not polymers of carbohydrates. Phospholipids are a type of lipid, DNA is a nucleic acid, and secondary structure refers to the folding pattern of proteins.Rate this question:
-
- 13.
What holds 2 monosaccharides together?
- A.
Glycosidic linkage
- B.
Ester linkage
- C.
Phosphodiester linkage
- D.
Peptide bond
Correct Answer
A. Glycosidic linkageExplanation
A glycosidic linkage is the bond that holds two monosaccharides together. It is a type of covalent bond formed between the hydroxyl group of one monosaccharide and the anomeric carbon of another monosaccharide. This linkage is important in the formation of disaccharides, such as sucrose and lactose, as well as polysaccharides, such as starch and cellulose. Glycosidic linkages are crucial for the structural integrity and function of carbohydrates in living organisms.Rate this question:
-
- 14.
What does glucose+glucose give you?
- A.
Maltose
- B.
Sucrose
- C.
Lactose
- D.
Galactose
Correct Answer
A. MaltoseExplanation
Glucose + glucose gives you maltose. Maltose is a disaccharide composed of two glucose molecules joined together by a glycosidic bond.Rate this question:
-
- 15.
What does glucose+fructose give you?
- A.
Maltose
- B.
Sucrose
- C.
Lactose
- D.
Galactose
Correct Answer
B. SucroseExplanation
When glucose and fructose combine, they form sucrose. Sucrose is a disaccharide composed of one glucose molecule and one fructose molecule. It is commonly found in table sugar and is a common sweetener used in food and beverages.Rate this question:
-
- 16.
What does glucose+galactose give you?
- A.
Maltose
- B.
Sucrose
- C.
Lactose
- D.
Sucrose
Correct Answer
C. LactoseExplanation
Glucose and galactose combine to form lactose. Lactose is a disaccharide sugar found in milk and dairy products. It is composed of one molecule of glucose and one molecule of galactose, linked together by a beta-1,4-glycosidic bond. Lactose is an important source of energy for infants and is broken down by the enzyme lactase in the small intestine to be absorbed into the bloodstream.Rate this question:
-
- 17.
What is starch?
- A.
A form of protein
- B.
A combination of many glucose molecules
- C.
A storage polysaccharide
- D.
Both B and C
Correct Answer
D. Both B and CExplanation
Starch is a storage polysaccharide that is made up of many glucose molecules. It is a complex carbohydrate that serves as a major energy source in many organisms. As a polysaccharide, starch is composed of long chains of glucose units, making it a combination of many glucose molecules. Therefore, the correct answer is both option B and C.Rate this question:
-
- 18.
What are the alpha glucoses?
- A.
Animal and Plant starch
- B.
Cellulose and chitin
- C.
Animal starch and chitin
- D.
Plant starch and cellulose
Correct Answer
A. Animal and Plant starchExplanation
The correct answer is plant starch and animal starch. Alpha glucoses are a type of glucose molecule that are linked together in a specific way. Plant starch, also known as amylose and amylopectin, is made up of alpha glucoses and is the main storage form of glucose in plants. Animal starch, also known as glycogen, is a highly branched polymer of alpha glucoses and is the main storage form of glucose in animals. Therefore, the correct answer includes both plant starch and animal starch as examples of alpha glucoses.Rate this question:
-
- 19.
What are the beta glucoses (structural polysaccharides?
- A.
Animal and Plant starch
- B.
Cellulose and chitin
- C.
Animal starch and chitin
- D.
Plant starch and cellulose
Correct Answer
B. Cellulose and chitinExplanation
Cellulose and chitin are both examples of beta glucoses, which are structural polysaccharides. Cellulose is the main component of plant cell walls and provides rigidity and strength to the structure. Chitin is found in the exoskeleton of arthropods and the cell walls of fungi, and it also provides support and protection. Animal and plant starch are not beta glucoses and do not have a structural role.Rate this question:
-
- 20.
What are the 2 plant starches?
- A.
Amylaose and Glycogen
- B.
Amylopectin and Glycogen
- C.
Amylose and Amylopectin
- D.
Glycogen and Glucose
Correct Answer
C. Amylose and AmylopectinExplanation
Amylose and amylopectin are two types of plant starches. Amylose is a linear polymer of glucose molecules, while amylopectin is a branched polymer. Both starches are made up of glucose units and serve as a storage form of energy in plants. Amylose and amylopectin are commonly found in grains, potatoes, and other starchy vegetables.Rate this question:
-
- 21.
What is animal starch called?
- A.
Amylopectin
- B.
Glucose
- C.
Amylose
- D.
Glycogen
Correct Answer
D. GlycogenExplanation
Glycogen is the correct answer because it is commonly known as animal starch. It is a complex carbohydrate that is stored in the liver and muscles of animals, including humans. Glycogen serves as a readily available source of energy and is broken down into glucose when needed by the body.Rate this question:
-
- 22.
What is cellulose used for?
- A.
Fungi and arthropod exoskeletons
- B.
Animal skeletons
- C.
Plant cell walls
- D.
Cell membranes
Correct Answer
C. Plant cell wallsExplanation
Cellulose is a complex carbohydrate that makes up the structural component of plant cell walls. It provides strength and rigidity to the cell, allowing plants to maintain their shape and withstand external pressures. Cellulose is not used in fungi and arthropod exoskeletons, animal skeletons, or cell membranes. Therefore, the correct answer is that cellulose is used for plant cell walls.Rate this question:
-
- 23.
What is chitin used for?
- A.
Fungi and arthropod exoskeletons
- B.
Animal skeletons
- C.
Plant cell walls
- D.
Cell membranes
Correct Answer
A. Fungi and arthropod exoskeletonsExplanation
Chitin is a structural polysaccharide that is primarily found in the cell walls of fungi and the exoskeletons of arthropods. It provides strength and rigidity to these organisms, allowing them to maintain their shape and protect their internal structures. Chitin is not used in animal skeletons, plant cell walls, or cell membranes.Rate this question:
-
- 24.
What are lipids?
- A.
Proteins
- B.
The basis for genetics
- C.
Sugars, starches ,etc..
- D.
Fats, oils, etc...
Correct Answer
D. Fats, oils, etc...Explanation
Lipids are organic molecules that include fats, oils, and other similar substances. They are characterized by their insolubility in water and their solubility in organic solvents. Lipids serve as a source of energy, insulation, and protection for organs. They also play a crucial role in the structure and function of cell membranes. Therefore, the correct answer is "Fats, oils, etc..." as lipids encompass these substances.Rate this question:
-
- 25.
What are lipids made with?
- A.
Glycerol and Glucose
- B.
Phosphate and Glucose
- C.
Glycerol and Fatty Acid
- D.
Phosphate and Fatty Acid
Correct Answer
C. Glycerol and Fatty AcidExplanation
Lipids are made with glycerol and fatty acids. Glycerol is a three-carbon alcohol molecule, while fatty acids are long hydrocarbon chains with a carboxyl group at one end. These two molecules combine through a dehydration reaction, where the hydroxyl group of glycerol reacts with the carboxyl group of the fatty acid, forming an ester bond. This process is called esterification and results in the formation of a lipid molecule, such as a triglyceride. Lipids play important roles in storing energy, insulating the body, and acting as structural components of cell membranes.Rate this question:
-
- 26.
How many carbons do fatty acids have?
- A.
14-16
- B.
16-18
- C.
18-20
- D.
20-22
Correct Answer
B. 16-18Explanation
Fatty acids are organic compounds that consist of a long hydrocarbon chain with a carboxyl group at one end. The number of carbons in a fatty acid can vary, but the most common range is 16-18 carbons. This range includes fatty acids such as palmitic acid (16 carbons) and stearic acid (18 carbons). Fatty acids with fewer than 16 carbons are considered short-chain fatty acids, while those with more than 18 carbons are considered long-chain fatty acids.Rate this question:
-
- 27.
What links fatty acids with glycerol?
- A.
Phosphodiester linkage
- B.
Peptide bond
- C.
Glycosidic linkage
- D.
Ester linkage
Correct Answer
D. Ester linkageExplanation
Fatty acids are linked to glycerol through ester linkages. Ester linkages are formed when a hydroxyl group of glycerol reacts with a carboxyl group of a fatty acid, resulting in the formation of an ester bond. This linkage is commonly found in triglycerides, which are the main components of fats and oils. The ester linkage allows for the storage and release of energy in the form of fatty acids, making it a crucial connection between fatty acids and glycerol.Rate this question:
-
- 28.
What is a monoglyceride?
- A.
1 glycercol + 1 fatty acid
- B.
Monomer of a protein
- C.
Monomer of a carbohydrate
- D.
A type of nucleic acid
Correct Answer
A. 1 glycercol + 1 fatty acidExplanation
A monoglyceride is formed by the esterification of one molecule of glycerol with one molecule of fatty acid. This reaction results in the formation of a single ester bond between the glycerol and fatty acid, producing a monoglyceride. Monoglycerides are commonly found in food as emulsifiers and are also important intermediates in lipid metabolism.Rate this question:
-
- 29.
What is a diglyceride?
- A.
1 glycercol + 2 fatty acids
- B.
Monomer of a protein
- C.
Monomer of a carbohydrate
- D.
A type of nucleic acid
Correct Answer
A. 1 glycercol + 2 fatty acidsExplanation
A diglyceride is a molecule composed of one glycerol molecule and two fatty acid molecules. Glycerol is a three-carbon alcohol, and fatty acids are long hydrocarbon chains with a carboxyl group at one end. When the glycerol molecule forms ester bonds with two fatty acid molecules, a diglyceride is formed. This molecule is commonly found in biological systems and is an important component of lipids, which are essential for energy storage and cell membrane structure.Rate this question:
-
- 30.
What is a triglyceride?
- A.
1 glycercol + 3 fatty acids
- B.
Monomer of a protein
- C.
Monomer of a carbohydrate
- D.
A type of nucleic acid
Correct Answer
A. 1 glycercol + 3 fatty acidsExplanation
A triglyceride is composed of one glycerol molecule and three fatty acid molecules. Glycerol is a type of alcohol with three hydroxyl groups, and fatty acids are long chains of carbon and hydrogen atoms with a carboxyl group at one end. When these components combine, they form a triglyceride molecule, which is a type of lipid and serves as a major source of energy in the body.Rate this question:
-
- 31.
What is another name for a triglyeride?
- A.
Sugar
- B.
Protein
- C.
Fat
- D.
DNA
Correct Answer
C. FatExplanation
A triglyceride is a type of fat molecule that is composed of three fatty acids attached to a glycerol molecule. It is the main form of fat storage in the body and is found in foods such as oils, butter, and animal fats. Therefore, "fat" is another name for a triglyceride.Rate this question:
-
- 32.
How many calories are in 1g of fat?
- A.
1
- B.
4
- C.
9
- D.
15
Correct Answer
C. 9Explanation
Each gram of fat contains 9 calories. Fat is a concentrated source of energy, providing more than double the calories per gram compared to carbohydrates or protein. This is why high-fat foods tend to be calorie-dense and can contribute to weight gain if consumed in excess.Rate this question:
-
- 33.
What does fat do?
- A.
Stores energy
- B.
Insulates heat and electricity
- C.
Absorbs shock
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
Fat serves multiple functions in the body. It stores energy in the form of adipose tissue, which can be used as fuel when needed. Additionally, fat acts as an insulator, helping to regulate body temperature and protect organs from extreme temperatures. It also provides insulation against electrical impulses in the nervous system. Furthermore, fat acts as a cushion, absorbing shock and protecting vital organs from injury. Therefore, all of the given options accurately describe what fat does in the body.Rate this question:
-
- 34.
What is a saturated fat?
- A.
A fat maxed out with hydrogens, which is bad
- B.
A fat maxed out with carbons, which is bad
- C.
A fat maxed out with hydrogens, which is good
- D.
A fat maxed out with carbons, which is good
Correct Answer
A. A fat maxed out with hydrogens, which is badExplanation
A saturated fat is a fat maxed out with hydrogens, which is bad. Saturated fats are considered less healthy because they are associated with an increased risk of heart disease when consumed in excess. They are characterized by having all available carbon bonds saturated with hydrogen atoms, resulting in a more solid or "saturated" state at room temperature. Common sources of saturated fats include red meat, full-fat dairy products, and certain tropical oils like coconut oil and palm oil.Rate this question:
-
- 35.
Are saturated fats straight or bent?
- A.
Straight
- B.
Bent
- C.
Neither
Correct Answer
A. StraightExplanation
Saturated fats are straight because they consist of single bonds between carbon atoms in their fatty acid chains. This straight structure allows saturated fats to pack tightly together, resulting in a solid or semi-solid state at room temperature. In contrast, unsaturated fats have double bonds between carbon atoms, causing a bend or kink in their fatty acid chains. This bent structure prevents unsaturated fats from packing tightly together, resulting in a liquid state at room temperature.Rate this question:
-
- 36.
Are unsaturated fats straight or bent?
- A.
Straight
- B.
Bent
- C.
Neither
Correct Answer
B. BentExplanation
Unsaturated fats are bent. Unsaturated fats have double bonds in their carbon chains, causing a kink or bend in the molecule. This double bond creates a rigid structure, preventing the fatty acid chains from packing tightly together. As a result, unsaturated fats are usually liquid at room temperature. On the other hand, saturated fats have single bonds in their carbon chains, allowing the fatty acid chains to pack tightly together and form a straight structure. Saturated fats are typically solid at room temperature.Rate this question:
-
- 37.
Name a quality of saturated fats
- A.
They are diglycerides
- B.
Bent molecule
- C.
Solid at room temp.
- D.
Liquid at room temp.
Correct Answer
C. Solid at room temp.Explanation
Saturated fats are solid at room temperature. This is because their molecular structure lacks double bonds, making them tightly packed and solid. In contrast, unsaturated fats have double bonds, which create kinks in their structure and keep them in a liquid state at room temperature. Therefore, the quality of being solid at room temperature is characteristic of saturated fats.Rate this question:
-
- 38.
Name a quality of unsaturated fats
- A.
They are diglycerides
- B.
Straight molecule
- C.
Solid at room temp.
- D.
Liquid at room temp.
Correct Answer
D. Liquid at room temp.Explanation
Unsaturated fats are liquid at room temperature. This is because they have double bonds in their carbon chain, which cause the molecules to have a kink or bend. This kink prevents the molecules from packing tightly together, resulting in a liquid state. In contrast, saturated fats do not have double bonds and have a straight carbon chain, allowing them to pack tightly together and be solid at room temperature.Rate this question:
-
- 39.
What does it mean if an unsaturated fat is bent?
- A.
It takes up more space, thus keeping membrane fluid
- B.
It takes up less space, thus keeping membrane fluid
- C.
It takes up more space, thus keeping membrane closed
- D.
It takes up less space, thus keeping membrane closed
Correct Answer
A. It takes up more space, thus keeping membrane fluidExplanation
When an unsaturated fat is bent, it takes up more space. This means that the fatty acid chains in the fat molecule are not packed tightly together, creating kinks or bends in the structure. This increased space between the fatty acid chains allows for more movement and flexibility, keeping the membrane fluid. A fluid membrane is important for various cellular processes, such as the movement of molecules and proteins across the membrane.Rate this question:
-
- 40.
What is a polyunsaturated fat?
- A.
An unsaturated fat that has many bent carbons
- B.
An unsaturated fat that is as close to being saturated as possible
- C.
An unsaturated fat that has been unsaturated many times
- D.
Nothing, no such term exists
Correct Answer
C. An unsaturated fat that has been unsaturated many timesExplanation
A polyunsaturated fat is an unsaturated fat that has been unsaturated many times. This means that it contains multiple double bonds between carbon atoms in its chemical structure. These double bonds cause the fat molecule to have a bent or kinked shape. Polyunsaturated fats are typically found in plant-based oils and are considered to be healthy fats when consumed in moderation. They are known to have beneficial effects on heart health and can help lower bad cholesterol levels in the body.Rate this question:
-
- 41.
How do phospholips form?
- A.
Phosphate attaches to one of the carbons of a lipid
- B.
Phosphorus attaches to one of the carbons of a lipid
- C.
Phosphate attaches to one of the oxygens of a lipid
- D.
Phosphorus attaches to one of the oxygens of a lipid
Correct Answer
A. Phosphate attaches to one of the carbons of a lipidExplanation
Phospholipids form when a phosphate group attaches to one of the carbons of a lipid molecule. This attachment creates a polar "head" region, while the lipid "tail" remains nonpolar. This unique structure allows phospholipids to form the basic building blocks of cell membranes, with the polar heads facing outward towards the watery environment and the nonpolar tails facing inward, creating a barrier between the inside and outside of the cell.Rate this question:
-
- 42.
What do phospholips do?
- A.
Make up cell walls
- B.
Give cells energy
- C.
Make up cell membranes
- D.
Carry out photosynthesis
Correct Answer
C. Make up cell membranesExplanation
Phospholipids are a type of lipid molecule that make up the cell membrane. They have a hydrophilic (water-loving) head and hydrophobic (water-fearing) tails, which arrange themselves in a bilayer to form the cell membrane. This structure provides a barrier that separates the inside of the cell from its external environment, controlling the movement of substances in and out of the cell. Therefore, phospholipids play a crucial role in making up cell membranes.Rate this question:
-
- 43.
What is the polar/hydrophyllic part of the phospholipid?
- A.
Phosphate part
- B.
Lipid part
- C.
Both
- D.
Neither
Correct Answer
A. Phosphate partExplanation
The polar/hydrophilic part of a phospholipid is the phosphate part. This is because the phosphate group contains a negatively charged oxygen atom, making it attracted to water molecules and allowing it to interact with the aqueous environment. The lipid part of the phospholipid, on the other hand, is hydrophobic and repels water. Therefore, the correct answer is the phosphate part.Rate this question:
-
- 44.
What is the non-polar/hydrophobic part of the phospholipid?
- A.
Phosphate part
- B.
Lipid part
- C.
Both
- D.
Neither
Correct Answer
B. Lipid partExplanation
The non-polar/hydrophobic part of a phospholipid is the lipid part. Phospholipids consist of a hydrophilic phosphate head and two hydrophobic lipid tails. The lipid part is composed of fatty acid chains, which are non-polar and repel water. This hydrophobic region is responsible for the phospholipid bilayer's structure, as it forms a barrier that prevents water-soluble molecules from freely crossing the membrane.Rate this question:
-
- 45.
What are cell membranes made of?
- A.
Chitin
- B.
Cellulose
- C.
Phospholipid Bilayer
- D.
None of the above
Correct Answer
C. Phospholipid BilayerExplanation
Cell membranes are made of a phospholipid bilayer. Phospholipids have a hydrophilic (water-loving) head and a hydrophobic (water-repelling) tail. In the bilayer arrangement, the hydrophilic heads face outward towards the watery environment both inside and outside the cell, while the hydrophobic tails face inward, creating a barrier that separates the cell's internal contents from the external environment. This structure allows the cell membrane to regulate the movement of substances in and out of the cell, maintaining cellular homeostasis.Rate this question:
-
- 46.
What is the head of a phospholipd?
- A.
Glycerol and phosphate
- B.
Fatty acids
- C.
Neither
- D.
Both
Correct Answer
A. Glycerol and phosphateExplanation
The head of a phospholipid is composed of glycerol and phosphate. Phospholipids are a type of lipid molecule that make up the cell membrane. They have a hydrophilic (water-loving) head made up of glycerol and phosphate, which is attracted to water. This head region is polar and interacts with the aqueous environment inside and outside of the cell. The fatty acid tails, on the other hand, are hydrophobic (water-hating) and make up the nonpolar tail region of the phospholipid.Rate this question:
-
- 47.
What is are the tails of a phospholipid?
- A.
Glycerol and phosphate
- B.
Fatty acids
- C.
Neither
- D.
Both
Correct Answer
B. Fatty acidsExplanation
The tails of a phospholipid are composed of fatty acids. Phospholipids are a type of lipid molecule that make up the cell membrane. They consist of a hydrophilic (water-loving) head made up of glycerol and phosphate, and hydrophobic (water-repelling) tails made up of fatty acids. The fatty acid tails are responsible for the phospholipid's ability to form a bilayer in the cell membrane, with the hydrophilic heads facing outward towards the watery environment and the hydrophobic tails facing inward, away from the water.Rate this question:
-
- 48.
What is cholesterol?
- A.
A steroid lipid with 5 fused rings
- B.
A phospholipid with 5 fused rings
- C.
A steroid lipid with 4 fused rings
- D.
A phospholipid with 4 fused rings
Correct Answer
C. A steroid lipid with 4 fused ringsExplanation
Cholesterol is a steroid lipid with 4 fused rings. Steroid lipids are a type of lipid molecule that have a structure consisting of four interconnected rings. Cholesterol is an essential component of cell membranes and is also involved in the production of hormones, vitamin D, and bile acids. Its structure consists of four rings, making it a steroid lipid.Rate this question:
-
- 49.
How much of the human body's dry weight is composed of protein?
- A.
30-50%
- B.
40-50%
- C.
50-75%
- D.
60-75%
Correct Answer
C. 50-75%Explanation
Approximately 50-75% of the human body's dry weight is made up of proteins. This includes enzymes, structural proteins like collagen, transport proteins, and many others that perform various functions in the body. It's worth noting, however, that this percentage can vary based on factors such as age, gender, and overall health.Rate this question:
-
- 50.
What is the monomer of protein?
- A.
Monosaccharide
- B.
Glycerol
- C.
Nucleotide
- D.
Amino acid
Correct Answer
D. Amino acidExplanation
Proteins are made up of long chains of amino acids, which are the monomers of proteins. Amino acids are organic compounds that contain an amino group (-NH2) and a carboxyl group (-COOH). They are the building blocks of proteins and are linked together through peptide bonds to form polypeptide chains. Therefore, the correct answer is amino acid.Rate this question:
-
Back to top