Exam 9 Multiple Choice Questions PDF

Memrizz Exam 9 Multiple Choice Questions What initiates the muscle contraction process? a) Contraction of the motor neuron. b) Release of calcium from the sarcoplasmic reticulum. c) Presence of ATP in muscle fibers. d) Release of potassium from muscle cells. Corr...

Memrizz Exam 9 Multiple Choice Questions What initiates the muscle contraction process? a) Contraction of the motor neuron. b) Release of calcium from the sarcoplasmic reticulum. c) Presence of ATP in muscle fibers. d) Release of potassium from muscle cells. Correct answer: Release of calcium from the sarcoplasmic reticulum. What role does troponin play in muscle contraction? a) Troponin releases ATP for energy. b) Troponin prevents muscle contraction. c) Troponin binds calcium and moves tropomyosin. d) Troponin binds directly to actin. Correct answer: Troponin binds calcium and moves tropomyosin. What happens to tropomyosin during muscle contraction? a) It binds more tightly to actin. b) It releases calcium back into the SR. c) It causes myosin to detach from actin. d) It moves away from myosin-binding sites on actin. Correct answer: It moves away from myosin-binding sites on actin. What constitutes the troponin-calcium complex? a) Myosin bound to actin filaments. b) Calcium bound to troponin protein. c) ATP interacting with actin. d) A signal from the motor neuron. Correct answer: Calcium bound to troponin protein. How are actin and myosin primarily regulated? a) By troponin and tropomyosin. b) By calcium and sodium levels. c) By ATP and creatine phosphate. d) By contraction of nearby muscles. Correct answer: By troponin and tropomyosin. What occurs if calcium does not bind to troponin? a) Muscle fibers will constantly contract. b) Muscles will become rigid immediately. c) Calcium will leak into the bloodstream. d) Actin and myosin cannot interact. Correct answer: Actin and myosin cannot interact. What is the neuromuscular junction? a) The point where calcium enters muscle cells. b) Where a motor neuron meets a muscle fiber. c) The region where actin and myosin interact. d) The area of delayed muscle relaxation. Correct answer: Where a motor neuron meets a muscle fiber. How does the neuromuscular junction contribute to muscle contraction? a) It triggers calcium release from sarcoplasmic reticulum. b) It serves as a storage site for calcium. c) It directly binds calcium to actin. d) It activates tropomyosin to contract muscles. Correct answer: It triggers calcium release from sarcoplasmic reticulum. Which protein covers the myosin-binding sites on actin at rest? a) Calcium. b) Troponin. c) Myosin. d) Tropomyosin. Correct answer: Tropomyosin. What results from the exposure of myosin-binding sites? a) Myosin will unlink from actin. b) Myosin binds to actin, leading to power stroke. c) Calcium will bind to tropomyosin. d) Tropomyosin will block the binding again. Correct answer: Myosin binds to actin, leading to power stroke. What is the key takeaway about muscle contraction? a) ATP is the only requirement for contraction. b) Calcium release leads to myosin-binding site exposure. c) Muscle contraction occurs without neural input. d) Myosin can bind to actin at rest. Correct answer: Calcium release leads to myosin-binding site exposure. What is the primary function of the Proximal Convoluted Tubule (PCT)? a) Reabsorption of water, ions, and nutrients. b) Filtration of blood through hydrostatic pressure. c) Secretion of hormones into the bloodstream. d) Storage of urine prior to excretion. Correct answer: Reabsorption of water, ions, and nutrients. What is the main role of the Distal Convoluted Tubule (DCT)? a) Initial filtration of blood particles. b) Final site for urine concentration. c) Absorption of nutrients and glucose. d) Selective reabsorption and secretion of ions. Correct answer: Selective reabsorption and secretion of ions. Where does the final reabsorption of water occur in the nephron? a) Proximal Convoluted Tubule. b) Collecting Duct. c) Glomerulus. d) Distal Convoluted Tubule. Correct answer: Collecting Duct. What characterizes the Ascending Limb of the Loop of Henle? a) It primarily absorbs glucose. b) It is the main site of initial filtration. c) It is impermeable to water. d) It stores waste products prior to exit. Correct answer: It is impermeable to water. What is the function of Bowman's Capsule? a) Reabsorbs sodium and chloride ions. b) Stores urine before excretion. c) Concentrates urine before leaving the kidney. d) Encloses the glomerulus and initiates filtration. Correct answer: Encloses the glomerulus and initiates filtration. How is blood filtered at the renal corpuscle? a) By active transport of sodium. b) Through hydrostatic pressure. c) In response to hormone signals. d) Via passive diffusion of nutrients. Correct answer: Through hydrostatic pressure. What is the primary function of Bowman's Capsule? a) Reabsorption of essential nutrients. b) Formation of glucose and amino acids. c) Filtration of blood plasma and small molecules. d) Secretion of waste products into urine. Correct answer: Filtration of blood plasma and small molecules. Which of the following is NOT a component of the filtrate? a) Water. b) Proteins. c) Ions. d) Waste products. Correct answer: Proteins. Where does the majority of reabsorption occur in the nephron? a) Collecting Duct. b) Proximal Convoluted Tubule (PCT). c) Loop of Henle. d) Distal Convoluted Tubule. Correct answer: Proximal Convoluted Tubule (PCT). What type of substances are typically removed during reabsorption? a) Undesired waste products. b) Excess water only. c) Hormones and enzymes. d) Substances the body needs from the filtrate. Correct answer: Substances the body needs from the filtrate. What is the zygote? a) The final stage of embryonic development. b) A solid ball of cells. c) A single fertilized cell. d) The blastula stage. Correct answer: A single fertilized cell. In which embryonic stage does the morula occur? a) 16-cell stage. b) After the blastula stage. c) Before the implantation stage. d) The final stage of development. Correct answer: 16-cell stage. Which layer is NOT part of the inner cell mass? a) Epiblast. b) Trophoblast. c) Hypoblast. d) Endoderm. Correct answer: Trophoblast. What characterizes the gastrula stage? a) It is the 16-cell solid ball stage. b) The final stage in early embryonic development. c) It exclusively focuses on reabsorption. d) It involves the filtration process. Correct answer: The final stage in early embryonic development. Which limb of the Loop of Henle is involved in reabsorption? a) Descending limb. b) Collecting duct. c) Ascending limb. d) Proximal convoluted tubule. Correct answer: Ascending limb. What does the term 'reabsorption' refer to in renal physiology? a) Adding waste products to urine. b) Concentrating urine for excretion. c) Removing substances needed by the body from filtrate. d) Filtrating blood for toxins. Correct answer: Removing substances needed by the body from filtrate. What is the first stage of embryogenesis in mammals? a) Morula b) Zygote c) Blastula d) Gastrula Correct answer: Zygote At what stage does the embryo become a solid ball of cells? a) Zygote Stage b) Blastula Stage c) Morula Stage d) Gastrula Stage Correct answer: Morula Stage What characterizes the blastula stage? a) Solid ball of cells b) Three germ layers c) Zygote formation d) Formation of a hollow structure Correct answer: Formation of a hollow structure Which stage follows the morula in embryogenesis? a) Blastula Stage b) Zygote Stage c) Gastrula Stage d) Cleavage Stage Correct answer: Blastula Stage What is the significance of the inner cell mass during gastrulation? a) It forms the embryonic sac b) It differentiates into three germ layers c) It creates the zygote d) It produces blastomeres Correct answer: It differentiates into three germ layers What are epiblast and hypoblast? a) Two layers of the inner cell mass b) Stages of embryo development c) Types of germ layers d) Forms of the zygote Correct answer: Two layers of the inner cell mass What is a blastomere? a) A stage in embryogenesis b) A type of germ layer c) The zygote structure d) An individual cell from cleavage divisions Correct answer: An individual cell from cleavage divisions What results from the cleavage divisions of the embryo? a) Development of the morula b) Creation of the gastrula c) Formation of the blastocyst d) Formation of the zygote Correct answer: Formation of the blastocyst At which stage does the embryo consist of about 16 cells? a) Zygote Stage b) Morula Stage c) Blastula Stage d) Gastrula Stage Correct answer: Morula Stage During which stage does cell differentiation primarily occur? a) Gastrula Stage b) Zygote Stage c) Morula Stage d) Blastula Stage Correct answer: Gastrula Stage What function do one-way valves serve in the lymphatic system? a) Facilitate bidirectional flow of lymph fluid. b) Absorb dietary fats from the bloodstream. c) Prevent backflow of lymph fluid towards circulatory system. d) Promote the growth of lymphocytes. Correct answer: Prevent backflow of lymph fluid towards circulatory system. How does the lymphatic system aid in fluid drainage? a) It filters out toxins from the bloodstream. b) It returns escaped fluid from blood vessels to circulation. c) It increases blood volume by producing lymph. d) It transports oxygen to body tissues. Correct answer: It returns escaped fluid from blood vessels to circulation. What mechanism aids in the propulsion of lymph through its vessels? a) Pumping by the heart muscle. b) Gravity pulling lymph downward. c) Absorption via blood capillaries. d) Contraction of adjacent skeletal muscles and smooth muscle. Correct answer: Contraction of adjacent skeletal muscles and smooth muscle. What types of cells does the lymphatic system produce for immune defense? a) Red blood cells and macrophages. b) Platelets and dendritic cells. c) B and T cells. d) Neutrophils and basophils. Correct answer: B and T cells. Where do B cells mature in the lymphatic system? a) In the thymus gland. b) In the lymph nodes. c) In the spleen. d) In the bone marrow. Correct answer: In the bone marrow. What are lacteals primarily responsible for? a) Transporting oxygen to body tissues. b) Absorbing dietary fats from the digestive system. c) Filtering toxins from blood. d) Producing red blood cells. Correct answer: Absorbing dietary fats from the digestive system. Which part of the small intestine contains lacteals? a) Duodenum. b) Ileum. c) Colon. d) Villi. Correct answer: Villi. What is a primary role of the lymphatic system? a) Regulate body temperature. b) Collect interstitial fluid and return it to circulation. c) Produce insulin for blood sugar levels. d) Create energy from nutrients. Correct answer: Collect interstitial fluid and return it to circulation. What is one of the immune functions of the lymphatic system? a) Producing digestive enzymes. b) Regulating hormonal levels in the body. c) Storing excess blood for emergencies. d) Supporting the production and maturation of lymphocytes. Correct answer: Supporting the production and maturation of lymphocytes. What are blastomeres? a) Cells that form the placenta. b) Cells that produce muscle tissue. c) Individual cells formed during early embryonic development. d) Cells found in the mature embryo. Correct answer: Individual cells formed during early embryonic development. At which stage does an embryo become a morula? a) When it reaches the 16 to 32-cell stage. b) When it forms a blastocoel. c) At 128-cell stage of development. d) Right after fertilization occurs. Correct answer: When it reaches the 16 to 32-cell stage. What characterizes the blastula stage of embryogenesis? a) Development of three germ layers. b) Formation of individual blastomeres. c) Presence of a primitive streak. d) Formation of a blastocoel, a hollow cavity. Correct answer: Formation of a blastocoel, a hollow cavity. What happens during the gastrula stage? a) Invagination of the epiblast into the primitive streak. b) Formation of blastomeres. c) Conversion of morula to blastula. d) Development of the circulatory system. Correct answer: Invagination of the epiblast into the primitive streak. What is the main function of the taxonomic hierarchy? a) To determine the evolutionary history. b) To describe embryonic stages of development. c) To classify organisms from broad to specific levels. d) To analyze genetic similarities among species. Correct answer: To classify organisms from broad to specific levels. Which classification levels are most closely related? a) Kingdom and Phylum. b) Order and Class. c) Species and Domain. d) Family and Genus. Correct answer: Family and Genus. Which mnemonic helps remember the taxonomic levels? a) Every Kid Plays With Good Toys. b) Dear King Philip Come Over For Good Soup. c) Animals Fight Predators During the Game. d) All Students Study Topics for Success. Correct answer: Dear King Philip Come Over For Good Soup. The family Felidae includes which of the following genera? a) Panthera and Felis. b) Canis and Ursus. c) Lynx and Vulpes. d) Equus and Bos. Correct answer: Panthera and Felis. What distinguishes Kingdom and Phylum in taxonomy? a) Both levels are equally broad. b) Phylum includes only animals. c) Kingdom encompasses diverse organisms, phylum is more specific. d) Kingdom consists of specific species. Correct answer: Kingdom encompasses diverse organisms, phylum is more specific. What is the primary outcome of meiosis? a) Two diploid daughter cells b) Five haploid daughter cells c) Four haploid daughter cells (gametes) d) Three diploid daughter cells Correct answer: Four haploid daughter cells (gametes) Which phases are included in Meiosis I? a) Prophase, Anaphase, Metaphase, Cytokinesis b) Prophase I, Metaphase I, Anaphase I, Telophase I c) Prophase II, Metaphase II, Anaphase II, Telophase II d) Interphase, Prophase, Anaphase, Telophase Correct answer: Prophase I, Metaphase I, Anaphase I, Telophase I During which stage do homologous chromosomes pair up? a) Metaphase I b) Anaphase I c) Telophase II d) Prophase I Correct answer: Prophase I What happens during crossing over? a) Separation of sister chromatids b) Formation of tetrads c) Exchange of genetic material between homologous chromosomes d) Replication of DNA Correct answer: Exchange of genetic material between homologous chromosomes What aligns along the metaphase plate during Metaphase I? a) Sister chromatids b) Tetrads (paired homologous chromosomes) c) Single chromosomes d) Diploid cells Correct answer: Tetrads (paired homologous chromosomes) What is the result of Telophase I and Cytokinesis? a) Formation of four diploid cells b) Replication of sister chromatids c) Separation of homologous chromosomes d) Formation of two haploid cells Correct answer: Formation of two haploid cells What marks the beginning of Meiosis II? a) Formation of tetrads b) Condensation of DNA into chromosomes again c) Duplication of chromosome pairs d) Disappearance of sister chromatids Correct answer: Condensation of DNA into chromosomes again During which phase do sister chromatids separate? a) Telophase I b) Anaphase II c) Prophase I d) Metaphase I Correct answer: Anaphase II What is a key reason for meiosis in sexual reproduction? a) Increases the total number of chromosomes b) Duplicates every chromosome c) Transmits identical genetic information d) Ensures gametes have half the chromosome number Correct answer: Ensures gametes have half the chromosome number What process increases genetic diversity during meiosis? a) Mitosis b) Crossing over c) DNA replication d) Cell differentiation Correct answer: Crossing over What is the primary result of meiosis? a) Replication of somatic cells b) Formation of gametes c) Production of stem cells d) Development of zygotes Correct answer: Formation of gametes During Prophase I, what happens to chromatin? a) It duplicates b) It condenses into chromosomes c) It becomes cytoplasm d) It remains unaltered Correct answer: It condenses into chromosomes What key event occurs during Prophase I of meiosis? a) Sister chromatids separate b) Tetrads line up c) Chromosomes disperse randomly d) Homologous chromosomes undergo crossing over Correct answer: Homologous chromosomes undergo crossing over What aligns along the metaphase plate in Metaphase I? a) Chromatids b) Chromatin c) Sister chromosomes d) Tetrads Correct answer: Tetrads What occurs during Anaphase II? a) Sister chromatids are separated b) Homologous chromosomes pair up c) Chromatin condenses d) Tetrads are formed Correct answer: Sister chromatids are separated What condition can arise from blood type incompatibility? a) Hemophilia b) Erythroblastosis fetalis c) Thalassemia d) Anemia Correct answer: Erythroblastosis fetalis What blood type combination can lead to erythroblastosis fetalis? a) Rh+ mother with Rh- baby b) Rh- mother with Rh- baby c) Rh+ mother with Rh+ baby d) Rh- mother with Rh+ baby Correct answer: Rh+ mother with Rh- baby Why does Rh- mother with Rh+ baby cause complications? a) If the mother is sensitized b) If the mother is Rh+ c) If the baby is Rh- d) If the mother is O type Correct answer: If the mother is sensitized Which blood type pairing typically does NOT cause issues? a) Rh- mother with Rh- baby b) Rh+ mother with Rh+ baby c) Rh+ mother with Rh- baby d) Rh- mother with Rh+ baby Correct answer: Rh- mother with Rh- baby What is important to understand in preventing erythroblastosis fetalis? a) Fetal development stages b) Maternal age factors c) Blood type compatibility d) Genetic mutations Correct answer: Blood type compatibility What rank separates Phylum and Order in taxonomy? a) Class b) Genus c) Species d) Family Correct answer: Class What ranks separate Order and Species in taxonomy? a) Class and Phylum b) Family and Genus c) Phylum and Kingdom d) Domain and Kingdom Correct answer: Family and Genus Which rank precedes Genus in taxonomy? a) Order b) Species c) Class d) Family Correct answer: Family What is the most specific taxonomic classification? a) Genus b) Species c) Family d) Domain Correct answer: Species What is the correct order of taxonomic classification from least to most specific? a) Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species b) Kingdom, Phylum, Domain c) Species, Genus, Family d) Class, Order, Phylum Correct answer: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species In meiosis, what occurs during the first event? a) Chromosomes of diploid cells condense. b) Sister chromatids are segregated c) Tetrads line up at midplate d) Homologous chromosomes cross over Correct answer: Chromosomes of diploid cells condense. What occurs during Prophase I of Meiosis? a) Sister chromatids separate b) DNA condenses into chromosomes. c) Homologous chromosomes line up d) Tetrads form Correct answer: DNA condenses into chromosomes. During which stage do homologous chromosomes line up at the plate? a) Anaphase I b) Prophase I c) Metaphase I d) Telophase I Correct answer: Metaphase I What happens in Anaphase I? a) Sister chromatids separate b) Homologous chromosomes are separated. c) Chromosomes condense d) DNA duplicates Correct answer: Homologous chromosomes are separated. What occurs at the end of Telophase I and Cytokinesis? a) DNA condenses into chromosomes b) Sister chromatids are separated c) Homologous chromosomes pair up d) Forms two haploid cells. Correct answer: Forms two haploid cells. What happens during Prophase II? a) Tetrads line up b) Cytoplasm divides c) Homologous chromosomes pair d) Chromosomes prepare for separation. Correct answer: Chromosomes prepare for separation. Which phase corresponds to the separation of sister chromatids? a) Metaphase I b) Anaphase II c) Telophase I d) Prophase I Correct answer: Anaphase II What occurs in Telophase II? a) Cytoplasm divides, forming haploid cells. b) Chromosomes condense into chromatin c) Sister chromatids pair up d) DNA replicates Correct answer: Cytoplasm divides, forming haploid cells. What is the Rhesus factor? a) A protein on the surface of red blood cells. b) A type of white blood cell c) A hormone produced in the brain d) An enzyme involved in digestion Correct answer: A protein on the surface of red blood cells. How can the Rhesus factor be present? a) It can only be positive. b) It can be present (+) or absent (-). c) It appears only during pregnancy. d) It varies with blood temperature. Correct answer: It can be present (+) or absent (-). What causes erythroblastosis fetalis? a) Maternal blood type produces extra platelets. b) Fetal blood causes stress in the mother. c) Maternal allergies affect fetal health. d) Maternal anti-Rh antibodies attack fetal erythrocytes. Correct answer: Maternal anti-Rh antibodies attack fetal erythrocytes. What conditions are required for erythroblastosis fetalis to occur? a) Rh+ mother with previous Rh- child. b) Rh- mother with prior Rh+ child. c) Rh- mother with another Rh- child. d) Rh+ mother with two Rh+ children. Correct answer: Rh- mother with prior Rh+ child. What happens when an Rh- mother has an Rh+ child? a) She remains immune to Rh factors. b) She protects against all blood types. c) She produces anti-Rh antibodies after exposure. d) She generates more red blood cells. Correct answer: She produces anti-Rh antibodies after exposure. What is the antibody response in an Rh+ mother with an Rh- baby? a) She produces excess anti-Rh antibodies. b) She does not produce anti-Rh antibodies. c) She produces anti-Rh antibodies attacking herself. d) She develops an immune reaction. Correct answer: She does not produce anti-Rh antibodies. What is the outcome for an Rh- mother with an Rh- baby? a) The mother rejects the baby immediately. b) Anti-Rh antibodies are produced. c) No antibodies are produced against Rh antigens. d) The baby is more vulnerable to diseases. Correct answer: No antibodies are produced against Rh antigens. When can erythroblastosis fetalis occur? a) With one Rh- child before two Rh+ children. b) After two pregnancies with Rh+ children. c) Only in the first pregnancy. d) If the mother has high blood pressure. Correct answer: After two pregnancies with Rh+ children. What is the key takeaway about Rh- mothers? a) They can never have Rh+ children. b) They should avoid having children altogether. c) Rh- mothers are immune to Rh+ children. d) They risk erythroblastosis fetalis with two Rh+ children. Correct answer: They risk erythroblastosis fetalis with two Rh+ children. Which kingdom includes organisms like tigers and ants? a) Fungi b) Plantae c) Animalia d) Bacteria Correct answer: Animalia What is a key characteristic of Rotifera? a) Large terrestrial animals b) Microscopic and aquatic zooplankton c) Photosynthetic organisms d) Bacterial pathogens Correct answer: Microscopic and aquatic zooplankton Which organisms belong to the kingdom Fungi? a) Algae and shrubs b) E. coli and streptococcus c) Protozoa and diatoms d) Yeasts, mushrooms, and Penicillin mold Correct answer: Yeasts, mushrooms, and Penicillin mold What type of organisms are included in Plantae? a) Euglena and slime molds b) Methanogens and halophiles c) Yeasts and Penicillin mold d) Shrubs, flowers, and algae Correct answer: Shrubs, flowers, and algae Which of the following is a group within Protista? a) Mold and mushrooms b) Ants and tigers c) E. coli and cyanobacteria d) Diatoms and slime molds Correct answer: Diatoms and slime molds What type of extremophiles do Archaea include? a) Fungi and protozoa b) Methanogens, thermophiles, and halophiles c) Diatoms and algae d) Echinoderms and arthropods Correct answer: Methanogens, thermophiles, and halophiles Which example belongs to the kingdom Bacteria? a) Yeast b) E. coli c) Euglena d) Tiger Correct answer: E. coli What mnemonic can help remember the phyla of Animalia? a) Easy Ways to Understand Fungi b) Privileged Children Play Nicely Rapidly And Maturely, Arthur Ensures Cooperation c) Kingdoms are Fun and Diverse d) Learning about Plants and Animals Correct answer: Privileged Children Play Nicely Rapidly And Maturely, Arthur Ensures Cooperation Which phylum is represented by 'Children' in the mnemonic? a) Chordata b) Porifera c) Cnidaria d) Echinodermata Correct answer: Cnidaria What does 'Maturely' refer to in the Animalia mnemonic? a) Mollusca b) Nematoda c) Annelida d) Arthropoda Correct answer: Mollusca Which phylum corresponds to 'Ensures' in the mnemonic? a) Arthropoda b) Porifera c) Echinodermata d) Platyhelminthes Correct answer: Echinodermata