Q&A Hero

Q: What process involves the destruction of worn-out organelles by lysosomes? A. exocytosis B. pinocytosis C. autophagy D. None apply.

Q: A cell which is actively involved in the detoxification of chemicals would contain large quantities of A. ribosomes. B. mitochondria. C. peroxisomes. D. rough endoplasmic reticulum.

Q: The main function of the peroxisome is to release energy from food molecules and transform the energy into usable ATP.

Q: Membrane enclosed organelles containing oxidative enzymes that form hydrogen peroxide are A. lysosomes. B. centrosomes. C. peroxisomes. D. chromosomes.

Q: What enzyme is needed to prevent excessive accumulation of hydrogen peroxide from peroxisome activity? A. peroxidase B. catalase C. oxidate D. maltase

Q: Chemicals stored in cells are called kinesins.

Q: Which of the following is NOT an example of an inclusion? A. glycogen B. actin C. melanin D. triglycerides

Q: Which type of lysosome contains undigested wastes? A. secondary lysosome B. residual body C. primary lysosome D. tertiary body

Q: The centrosome is responsible for A. making cilia. B. making microtubules. All apply.

Q: All body cells have motile cilia with a "9+2" structure.

Q: Almost every body cell has a single nonmotile primary cilium with a "9+0" structure.

Q: Primary cilia may serve sensory functions such as vision.

Q: A flagellum has A. a "9+0" structure. B. a "9+2" structure. C. no microtubules. D. microvilli as its structure.

Q: Folds of the plasma membrane that increase surface area are called A. cilia. B. microvilli. C. flagella. D. vesicles.

Q: Cells with large numbers of microvilli on their apical surface are probably involved in A. movement of the body. B. reabsorption of molecules during production of urine. C. detoxification of chemicals. D. secretion of neurotransmitters.

Q: The cytoskeleton of a cell can serve as a railway that can transport organelles and molecules to different intracellular destinations.

Q: Microtubules and microfilaments are the primary components of the A. cytosol. B. nucleus. C. cytoskeleton. D. plasma membrane.

Q: Which of the following is NOT a molecular motor used to move substances along the cytoskeleton? A. melanin B. kinesin C. myosin D. dynein

Q: Phagocytosis differs from endocytosis in that with phagocytosis A. the plasma membrane invaginates to produce a furrow that pinches off inside the cell. B. the plasma membrane extends outwards with pseudopods to surround the substance. C. specific membrane receptors bind to the molecules to be brought into the cell. D. None apply.

Q: The only flagellated cells in humans are A. ova. B. sperm. C. goblet cells. D. tumor cells.

Q: Which of the following locations have ciliated cells? A. respiratory and digestive systems B. female reproductive and lymphatic systems C. respiratory and female reproductive systems D. digestive and lymphatic systems

Q: The backbone of a DNA molecule is a chain of A. alternating deoxyribose sugar and phosphate. B. alternating phosphate and nitrogen. C. alternating nitrogenous bases. D. alternating deoxyribose and ribose sugars.

Q: Which of the following is NOT a function of a purine-containing nucleotide? A. neurotransmitter B. hormone C. energy carrier D. coenzymes

Q: Receptor-mediated endocytosis would allow cells to selectively remove molecules from the extracellular fluid.

Q: Intake of a specific molecule from the extracellular compartment by a cell occurs through A. phagocytosis. B. exocytosis. C. receptor-mediated endocytosis. D. apoptosis.

Q: The process by which cells secrete cellular products into the extracellular environment is A. phagocytosis. B. endocytosis. C. exocytosis. D. pinocytosis.

Q: Release of neurotransmitters occurs via A. exocytosis. B. endocytosis. C. phagocytosis. D. pinocytosis.

Q: Pinocytosis is a type of exocytosis.

Q: Cholesterol and AIDS viruses are taken into cells by receptor-mediated endocytosis.

Q: The "spiral staircase" structure of DNA is referred to as the A. tertiary structure. B. spiral structure. C. the double helix. D. the twist of life.

Q: Which of the following is NOT one of the three types of RNA? A. dRNA B. tRNA C. rRNA D. mRNA

Q: The base that is NOT found in RNA is A. thymine. B. guanine. C. cytosine. D. uracil.

Q: Which of the following is NOT a difference between DNA and RNA? A. They have different sugars. B. RNA is a single strand, while DNA is a double strand. C. DNA has thymine, while RNA has uracil. D. They both can leave the nucleus to perform their functions.

Q: In DNA, cytosine forms a complementary base pair with adenine.

Q: The nitrogenous base adenine is a A. purine. B. pyrimidine. C. steroid. D. prostaglandin.

Q: Which of the following is NOT a component of DNA? A. phosphate B. deoxyribose sugar C. guanine D. uracil

Q: The human genome refers to A. all living human beings. B. the total variations in human cells. C. all of the genes in the cell. D. human mutations caused by gene defects.

Q: How many different amino acids are known? A. 10 B. 25 C. 30 D. 20

Q: What holds a protein in its tertiary structure? A. hydrogen bonds between nearby amino acids B. weak chemical bonds between widely spaced amino acids C. disulfide bonds between sulfur groups on cysteines D. Both weak chemical bonds between widely spaced amino acids and disulfide bonds between sulfur groups on cysteines are correct.

Q: How many amino acids are present for a polypeptide chain to be called a protein? A. 3 B. 30 C. 50 D. 100

Q: Proteins that combine with other molecules are said to be condensed.

Q: The specific shape of a protein determines its function.

Q: A protein that is combined with another type of molecule like a carbohydrate is A. conjugated. B. denatured. C. hydrolyzed. D. complemented.

Q: Which of the following is NOT a function of proteins in the body? A. carriers for membrane transport B. enzymes C. compose genes D. receptors for regulator molecules

Q: Keratin and collagen are considered _______ proteins. A. functional B. structural C. fibrous D. Both structural and fibrous are correct.

Q: All amino acids contain carboxyl and amino groups.

Q: The specific sequence of amino acids in a polypeptide is known as the primary protein structure.

Q: The white part of a cooked egg is due to denatured albumin proteins.

Q: _______________ is a structural protein found in tendons and ligaments. A. Collagen B. Keratin C. Myosin D. Fibrin

Q: Peptide bonds are formed by the process of A. ketosis. B. hydrolysis. C. dehydration synthesis. D. aromatization.

Q: The secondary structure of proteins is/are A. the linear arrangement of amino acids in the molecule. B. alpha helix coils and beta-pleated sheet folds of a protein strand. C. due to the interaction between protein subunits. D. stabilized when a protein is denatured.

Q: The primary structure of proteins is/are A. the linear arrangement of amino acids in the molecule. B. alpha helix coils and beta-pleated sheet folds of a protein strand. C. due to the interaction between protein subunits. D. stabilized when a protein is denatured.

Q: The subunit of protein is the A. fatty acid. B. nucleic acid. C. amino acid. D. carboxylic acid.

Q: What characteristic of phospholipids allows them to form the double layer seen in cell membranes? A. They are amphipathic. B. They are totally nonpolar. C. They are soluble in water. D. They are totally hydrophobic.

Q: Lipids containing glycerol would include _______________ and ____________. A. triglycerides, steroids B. prostaglandins, phospholipids C. triglycerides, phospholipids D. steroids, prostaglandins

Q: ________________ are liver synthesized derivatives of free fatty acids that can be used as an immediate source of energy by many organs. A. Glycerols B. Ketone bodies C. Steroids D. Cholesterols

Q: _____________ are fatty acids with a cyclic hydrocarbon group. A. Triglycerides B. Prostaglandins C. Proteins D. Carbohydrates

Q: A molecule that is part polar and part nonpolar is called A. an enantiomer. B. a ketone body. C. unsaturated. D. amphipathic.

Q: This group of organic compounds acts as surfactants: A. carbohydrates B. phospholipids C. nucleic acids D. prostaglandins

Q: In the formation of triglycerides, A. hydroxyl and carbonyl groups interact. B. amino and carbonyl groups interact. C. carboxyl and amino groups interact. D. carboxyl and hydroxyl groups interact.

Q: Which of the following is NOT true of unsaturated fatty acids? A. They contain one or more double bonds. B. They are usually liquid at room temperature. C. They contain a maximal number of hydrogen atoms. D. They contain less than the maximum number of hydrogen atoms.

Q: Which of the following is NOT true of phospholipids? A. They are glycolipids originally isolated from the prostate gland. B. They are major components of the cell membrane. C. They have a polar head and a nonpolar tail. D. They are amphipathic molecules.

Q: Ketosis A. occurs when stored fats are rapidly degraded by the body. B. stimulates an increased blood pH. C. may lead to alkalosis. D. occurs as the concentration of ketones in the urine decreases.

Q: Which of the following describes a trans-fat? A. Has carbon-carbon single bonds. B. Has carbon-carbon double bonds with hydrogens on opposite sides of the bonds. C. Has carbon-carbon double bonds with hydrogens on the same side of the bonds. D. The fatty acids form a bent chain.

Q: Which of the following is NOT true of steroids? A. They have three 6-carbon rings joined to one 5-carbon ring. B. They contain a variety of functional groups. C. They are derived from palmitate. D. They differ in the position of the double covalent bonds between the carbon atoms in the rings.

Q: Which of the following is NOT a derivative of cholesterol? A. corticosteroids B. vitamin D3 C. aldosterone D. lecithin

Q: Phospholipid molecules will form aggregates called ______ when placed in water. A. surfactants B. ketone bodies C. prostaglandins D. micelles

Q: In order to maintain proper health, total dietary fat intake should not exceed _______________ of total dietary energy intake. A. 10% B. 20% C. 30% D. 40%

Q: Which of the following is NOT a type of lipid? A. prostaglandins B. triglycerides C. cholesterol D. glycogen

Q: An example of a monosaccharide is A. maltose. B. sucrose. C. glucose. D. glycogen.

Q: Glucose is stored as a polysaccharide to prevent osmosis of water into the cells.

Q: Which of the following is NOT a disaccharide? A. fructose B. sucrose C. maltose D. lactose

Q: Which of the following polysaccharides cannot be digested by animals themselves? A. glycogen B. cellulose C. starch D. All apply.

Q: Unsaturated fatty acids contain more hydrogen atoms than saturated fatty acids of the same length.

Q: Rapid, uncontrolled hydrolysis of body fats can result in ketoacidosis.

Q: Corticosteroids are a type of lipid commonly found in cell membranes.

Q: Steroids are derived from cholesterol.

Q: Fructose is a ketone.

Q: _________ are molecules with the same ratio of atoms but different arrangements of atoms. A. Isotopes B. Structural isomers C. Stereoisomers D. Radioactive isotopes

Q: Covalent bonds are formed between monosaccharides through dehydration synthesis.