chapter 34 google form

Sex determination in humans and other mammals is dictated by the presence of sex chromosomes. Are there different factors that determine the sex of other types of animals? A. No, the sex of an individual is only determined by the presence of sex chromosomes. B. Yes, temperature also determines the sex of an individual. C. Yes, humidity and temperature determine the sex of an individual. D. Yes, pH and humidity determine the sex of an individual.

B. Yes, temperature also determines the sex of an individual.

Which germ layer forms the skin cells? A. endoderm B. ectoderm C. mesoderm D. trophoblast

B. ectoderm

Gastrulation is the process in which the cells in the blastula rearrange themselves and form three layers of cells. Each layer will differentiate into a different organ system. At what point of development do the major organs begin to develop? A. fertilization B. first trimester C. second trimester D. third trimester

B. first trimester

In sexual reproduction, gametes with either an X or Y chromosome are formed in males, whereas gametes in females contain a single X chromosome. What is the nature of both male and female gametes? A. diploid B. haploid C. homozygous D. heterozygous

B. haploid

Which type of short-term contraceptive method is generally more effective than others? A. barrier B. hormonal implants C. natural family planning D. withdrawal

B. hormonal implants

Which part of the male reproductive system produces most of the semen? A. scrotum B. seminal vesicles C. seminiferous tubules D. prostate gland

B. seminal vesicles

How is an oocyte released from a human ovary so it can enter the oviduct? A. the beating action of the flagellum on the oocyte B. the force of the follicular ejection directing the oocyte into the oviduct C. the wavelike beating of cilia lining the oviduct D. muscular contraction of the ovaries

B. the force of the follicular ejection directing the oocyte into the oviduct

If a plant species with a diploid number of 32 is crossed with another plant species with a diploid number of 24, what will be the diploid number of the resulting first generation of offspring? After the zygote multiplies to form a mass of cells, what is the chromosome number of each cell? A. 32, 28 B. 24, 24 C. 28, 28 D. 28, 32

C. 28, 28

What is the nature of the oogonium and the secondary oocyte? Which process results in the formation of the secondary oocyte? A. A diploid oogonium forms a haploid oocyte by the process of mitosis. B. A haploid oogonium forms a diploid oocyte by the process of meiosis. C. A diploid oogonium forms a haploid oocyte by the process of meiosis. D. A haploid oogonium forms a haploid haploid oocyte by the process of meiosis.

C. A diploid oogonium forms a haploid oocyte by the process of meiosis.

Explain mechanisms which hormones from brain and ovaries interact, eventually leading to menstruation. A. After release of egg from follicle, corpus luteum formed, inhibits FSH and LH production, inhibits GnRH production, no other follicle to develop. When no fertilization, corpus luteum degenerates progesterone level declines, breakdown of myometrium and start of menstrual cycle. B. After release of egg from follicle, corpus luteum formed, inhibits FSH and LH production, inhibits GnRH production, no other follicle to develop. When no fertilization, corpus luteum degenerates progesterone level declines, breakdown of endometrium and start of menstrual cycle. C. After release of egg from follicle, corpus luteum formed, inhibits FSH and LH production, facilitates GnRH production, no other follicle to develop. When no fertilization, corpus luteum degenerates progesterone level declines, breakdown of endometrium and start

C. After release of egg from follicle, corpus luteum formed, inhibits FSH and LH production, facilitates GnRH production, no other follicle to develop. When no fertilization, corpus luteum degenerates progesterone level declines, breakdown of endometrium and start of menstrual cycle.

Compare and contrast spermatogenesis and oogenesis. A. Both are gametogenesis that takes place through mitosis. Spermatogenesis is the formation of four sperm in the testes in males. Formation of one ovum in the ovaries in females is called oogenesis. B. Both are gametogenesis that takes place through meiosis. Spermatogenesis is the formation of four sperm in the testes in males. Formation of four ova in the ovaries in females is called oogenesis. C. Both are gametogenesis that takes place through meiosis. Spermatogenesis is formation of four sperm in the testes in males. Formation of one ovum in the ovaries in females is called oogenesis. D. Both are gametogenesis that takes place through meiosis. Spermatogenesis is formation of one sperm in the testes in males, while formation of one ovum in the ovaries in females is called oogenesis.

C. Both are gametogenesis that takes place through meiosis. Spermatogenesis is formation of four sperm in the testes in males. Formation of one ovum in the ovaries in females is called oogenesis.

Which method produces genetically-unique offspring? A. parthenogenesis B. budding C. fragmentation D. sexual reproduction

D. sexual reproduction

Due to global climate change and pollution, a lake experiences changes in temperature and pH. The lake has many species, including sexually reproducing frogs, water fleas that multiply by parthenogenesis, hydra that multiply by budding, and sponges that multiply by fragmentation. Which of these species will most likely survive the changing conditions of the lake? A. hydra B. sponges C. water fleas D. sexually-reproducing frogs

D. sexually-reproducing frogs

The spermatheca, which is found in many insects, worms, and mollusks, is useful for _____. A. spermatogenesis B. sperm motility C. growth of embryos D. storing sperm and as a site for fertilization

D. storing sperm and as a site for fertilization

How many eggs are produced as a result of one meiotic series of cell divisions? A. 1 B. 2 C. 3 D. 4

A. 1

How does the feedback mechanism of hormones lead to muscular contractions during labor? A. A feedback relay occurs between the uterus, hypothalamus, and posterior pituitary to assure an adequate supply of oxytocin, which causes the contraction of smooth muscles of the uterus, leading to the birth of the baby. B. The posterior pituitary continuously produces oxytocin, which is sufficient for muscular contraction in the uterus, thereby causing the birth of the baby. C. A feedback relay occurs between the uterus, hypothalamus, and posterior pituitary to assure an adequate supply of prolactin, which causes the contraction of the smooth muscles of the uterus, leading to the birth of the baby. D. A feedback relay occurs between the uterus, hypothalamus, and posterior pituitary to assure an adequate supply of progesterone, which causes the contraction of the smooth muscles of the uterus, leading to the birth of the baby.

A. A feedback relay occurs between the uterus, hypothalamus, and posterior pituitary to assure an adequate supply of oxytocin, which causes the contraction of smooth muscles of the uterus, leading to the birth of the baby.

Which of the following statements best summarizes the factors controlling symmetry? A. Axis formation is genetically determined. B. Body symmetry is independent of genes. C. Body symmetry is determined at the blastula stage. D. Body symmetry is determined as the embryo grows in length.

A. Axis formation is genetically determined.

Multiple hormones work together to coordinate the female reproductive cycle. Which of these hormones is also responsible for the development of female secondary sexual characteristics, including breast development and hip widening? A. estrogen B. progesterone C. follicle stimulating hormone D. luteinizing hormone

A. estrogen

What happens to the number of cells during cleavage? A. increases B. decreases C. doubles with every cell division D. does not change significantly

A. increases

The blastula stage is a mass of specialized cells. Of the following, which forms the liver cells? A. inner cell mass B. trophoblast C. blastula D. blastomere

A. inner cell mass

The neural plate undergoes folding and movement of cells to form which structure? A. neural tube B. epidermis C. mesoderm D. neural cord

A. neural tube

Which term applies to egg development outside the female with nourishment derived from a yolk? A. oviparity B. viviparity C. ovoviparity D. ovovoparity

A. oviparity

Which hormone is primarily responsible for the contractions during labor? A. oxytocin B. estrogen C. β-HCG D. progesterone

A. oxytocin

Before pregnancy, progesterone is produced by the ovaries to thicken the endometrial lining and ensure pregnancy. During the third trimester of pregnancy, which organ produces progesterone? A. placenta B. endometrial lining C. chorion D. corpus luteum

A. placenta

What does a female contraceptive pill that inhibits the release of GnRH from the hypothalamus do? A. reduce the secretion of FSH and LH from the anterior pituitary gland B. initiate ovulation C. increase the flow phase of the menstrual cycle D. increase the production of estrogen and progesterone by the ovaries

A. reduce the secretion of FSH and LH from the anterior pituitary gland

Sea stars are broken apart by workers to save the clams they feed on, and then thrown back into the ocean. Often the numbers of sea stars are seen to double after this. Give the reason why this happens. A. regeneration B. fragmentation C. budding D. the presence of suitable conditions

A. regeneration

Which structure is only related to the male urinary system, as opposed to the male reproductive system? A. urinary bladder B. cowper's gland C. bulbourethral gland D. urethra

A. urinary bladder

Compare the specialization of reproductive structures found in different types of land animals. A. In birds cloaca is used to transfer sperm, in mammals the penis and vagina allow direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the testes and sperm maturing in the ovaries. B. In birds cloaca is used to transfer sperm, in mammals the penis and vagina allow direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes. C. In birds sperm are transferred via the spermatheca, in mammals the penis and vagina allow direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes. D. In birds cloaca is used to transfer sperm, in mammals penis and vagina allow direct delivery. Insects always use parthenogenesis.

B. In birds cloaca is used to transfer sperm, in mammals the penis and vagina allow direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes.

What stimulates Leydig cells in the testes to produce testosterone? A. FSH B. LH C. inhibin D. estrogen

B. LH

Which of the following statements about the menstrual cycle is TRUE? A. Estrogen levels rise during the luteal phase of the ovarian cycle and the secretory phase of the uterine cycle. B. Menstruation occurs much before LH and FSH levels peak. C. Menstruation occurs after progesterone levels rise. D. Progesterone levels rise before ovulation, while estrogen levels rise after.

B. Menstruation occurs much before LH and FSH levels peak.

What is the advantage of sexual reproduction? A. Sexual reproduction allows animals to conserve resources and reproduce only during optimal conditions. B. Sexual reproduction results in offspring with diverse phenotypes, which may enhance survival of a population in a changing environment. C. Sexual reproduction guarantees that both parents will provide parental care. D. Sexual reproduction yields more numerous offspring more rapidly than is possible with asexual reproduction.

B. Sexual reproduction results in offspring with diverse phenotypes, which may enhance survival of a population in a changing environment.

Which of the following statements regarding early embryonic stages is false? A. The endoderm, mesoderm, and ectoderm are germ layers. B. The trophoblast is a germ layer. C. The inner cell mass is a source of embryonic stem cells. D. The blastula is often a hollow ball of cells.

B. The trophoblast is a germ layer.

Which hormone prepares the endometrial lining of the uterus for potential implantation? A. testosterone B. estrogen C. GnRH D. progesterone

D. progesterone

What are the events that take place in a non-pregnant woman after ovulation? A. Bc fertilized egg not implanted in uterus, corpus luteum degenerates, levels of estrogen and progesterone decrease. Endometrium begins to degenerate as the progesterone level drops, next menstrual cycle. B. Bc fertilized egg not implanted in uterus, corpus luteum degenerates, levels of estrogen and progesterone increase. Endometrium begins to degenerate as the estrogen level increases, next menstrual cycle. C. Bc fertilized egg not implanted in uterus, corpus luteum degenerates, levels of estrogen and progesterone increase. Endometrium begins to degenerate as the progesterone level rises, next menstrual cycle. D. Bc fertilized egg not implanted in uterus, corpus luteum degenerates, levels of estrogen and progesterone decrease. Myometrium begins to degenerate as the progesterone level drops, next menstrual cycle.

A. Bc fertilized egg not implanted in uterus, corpus luteum degenerates, levels of estrogen and progesterone decrease. Endometrium begins to degenerate as the progesterone level drops, next menstrual cycle.

What occurs as a result of fertilization of an egg and sperm? A. Fertilization restores diploidy. B. Fertilization always results in a viable embryo. C. Fertilization merges two diploid cells into a haploid cell. D. Fertilization precedes ovulation.

A. Fertilization restores diploidy.

In both males and females, the hormones FSH and LH play a critical role in the reproductive phase. What regulates the secretion of these hormones? A. GnRH B. estrogen C. progesterone D. inhibin

A. GnRH

The endocrine system incorporates feedback mechanisms that maintain homeostasis. Which of the following mechanisms demonstrates negative feedback by the reproductive system in mammals? A. Increasing levels of testosterone inhibit the production of GnRH, LH, and FSH by the hypothalamus and pituitary. B. LH and FSH stimulate the interstitial cells of Leydig to release testosterone. C. The growing follicle starts releasing estrogen in increasing amounts. D. The corpus luteum releases progesterone after ovulation.

A. Increasing levels of testosterone inhibit the production of GnRH, LH, and FSH by the hypothalamus and pituitary.

Spawning is often triggered by a signal such as water temperature or day length. What is an advantage of using this type of signal versus using individual courtship behaviors? A. It allows many individuals to spawn simultaneously without males and females having to choose individual mates. B. It is the only way that males and females can time gamete release simultaneously. C. These are the only types of signals that can be used. D. It increases the distance that gametes can travel.

A. It allows many individuals to spawn simultaneously without males and females having to choose individual mates.

In sexual reproduction, two cells of a species combine to form another cell. Why is this useful? A. It produces new combination of genes, which enables offspring to survive during environmental changes. B. It results in the production of many offspring in a short period of time. C. It does not involve gamete formation and requires less energy. D. It allows immobile organisms to reproduce in the absence of a mate.

A. It produces new combination of genes, which enables offspring to survive during environmental changes.

What do the rising levels of FSH and LH in the follicular phase cause? A. The follicles on the surface of the ovary start growing in preparation for ovulation. B. The endometrium starts to thicken. C. The corpus luteum starts secreting progesterone. D. One of the mature follicles bursts, releasing the egg.

A. The follicles on the surface of the ovary start growing in preparation for ovulation.

After the blastula is formed, where do the embryonic stem cells and germ layers originate? A. The inner cell mass contains embryonic stem cells, which arrange themselves into the three germ layers. B. The trophoblast in the blastula contains embryonic stem cells, which arrange themselves into three germ layers. C. The inner cell mass contains embryonic stem cells, whereas the germ cells originate from the trophoblast. D. The embryonic stem cells and germ layers originate from the blastocoel present inside the blastula.

A. The inner cell mass contains embryonic stem cells, which arrange themselves into the three germ layers.

What characterizes the acrosomal reactions? A. The sperm degrades the outermost layer of the egg to penetrate it. B. motility of the sperm C. fusion of the egg and sperm D. breakdown of the envelope covering the sperm head

A. The sperm degrades the outermost layer of the egg to penetrate it.

How are the offspring of viviparous animals different from the offspring of oviparous animals? A. They are protected from the external environment. B. They are produced in higher numbers. C. They can live longer. D. They can utilize nutrients better.

A. They are protected from the external environment.

What happens before the baby and placenta are expelled? A. Thinning and dilation of the cervix take place. B. There is increased blood flow to the baby. C. Enlargement of the uterus takes place. D. Increased production of estrogen occurs.

A. Thinning and dilation of the cervix take place.

Which of the following events activate the germ cells at puberty to produce spermatozoa? A. activation by gonadotropin-releasing hormone B. activation by increased hair growth C. increase in blood volume D. increase of secretion of testosterone

A. activation by gonadotropin-releasing hormone

External fertilization most commonly occurs in which type of environment? A. aquatic B. forests C. savanna D. steppe

A. aquatic

Which method of reproduction produces identical offspring and is most successful in a stable environment? A. asexual reproduction B. sexual C. conjugation D. inbreeding

A. asexual reproduction

How does a reproductive hormone that is secreted directly from the anterior pituitary stimulate the reproductive organs to produce hormones? A. by traveling through the blood to reach the target organs B. by binding with proteins to reach the reproductive organs C. by sending a chemical messenger to activate the reproductive organs D. by converting into an active form before targeting the reproductive organs

A. by traveling through the blood to reach the target organs

Which female organ has the same embryonic origin as the penis? A. clitoris B. labia majora C. greater vestibular glands D. vagina

A. clitoris

Which of the following structures is involved in mating in birds? A. cloaca B. spermatheca C. uterus D. coelom

A. cloaca

Describe the possible event that would occur if the corpus luteum did not produce increasing amounts of progesterone. A. The implanted zygote will not be able to derive sufficient nutrition from the endometrium. B. Even if fertilization is successful, the zygote may not be able to implant successfully. If it does manage to implant, it will not be able to derive sufficient nutrition from the myometrium. C. Even if fertilization is successful, the zygote may not be able to implant successfully. If it does manage to implant, it will not be able to derive sufficient nutrition from the endometrium. D. The contraction of the uterus during childbirth and lactation will not take place, causing problems and complications in the mother.

C. Even if fertilization is successful, the zygote may not be able to implant successfully. If it does manage to implant, it will not be able to derive sufficient nutrition from the endometrium.

With the onset of menopause, the follicles stop responding to which of the following hormones? A. estradiol and progesterone B. progesterone and estrogen C. FSH and LH D. FSH and GnRH

C. FSH and LH

Explain the fate of the newly released secondary oocyte after ovulation. A. If it fuses with a sperm, the resulting zygote enters the cervix for implantation. If it is not fertilized, it will return to the oviduct. B. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will return to oviduct. C. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will degrade and exit the body. D. If it fuses with a sperm, the resulting zygote enters the cervix for implantation. If it is not fertilized, it will degrade and exit the body.

C. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will degrade and exit the body.

What are some advantages of internal compared with external fertilization? A. Internal fertilization leads to more genetic variations and increases the survival rates of offsprings. B. Internal fertilization increases the survival rates of offspring, and large numbers of offspring are produced. C. Internal fertilization increases the survival rates of offspring, and the chance of fertilization with a specific partner also increases. D. Internal fertilization increases the survival rates of offspring and decreases the chance of fertilization with a specific partner.

C. Internal fertilization increases the survival rates of offspring, and the chance of fertilization with a specific partner also increases.

Why is sexual reproduction useful when only half the individuals reproduce and two cells must combine to form a new cell? A. It completes in a very short period of time. B. It results in the rapid production of many offspring. C. It increases genetic diversity, allowing organisms to survive in an unpredictable environment. D. It requires less energy and leads to genetic variation in the offspring.

C. It increases genetic diversity, allowing organisms to survive in an unpredictable environment.

Why is broadcast spawning considered advantageous? A. Production of many eggs increases the chance of fertilization. B. Production of many sperm increases the chance of fertilization. C. It results in mixing of genes and greater genetic diversity. D. Animals that are motile carry out this process.

C. It results in mixing of genes and greater genetic diversity.

Which hormone is released by the anterior pituitary as a part of the positive feedback loop between it and the ovary? A. Progesterone B. GnRH C. LH D. Estradiol

C. LH

What is necessary for normal human fertilization to occur? A. Many eggs must be released. B. The uterus must be enlarged. C. One sperm needs to penetrate one egg. D. Secretion of pituitary FSH and LH must decrease.

C. One sperm needs to penetrate one egg.

Which of the following statements is false? A. Budding is a method of asexual reproduction. B. Fragmentation is a method of asexual reproduction. C. Parthenogenesis is a type of sexual reproduction that produces diverse offspring. D. Binary fission is a method of asexual reproduction.

C. Parthenogenesis is a type of sexual reproduction that produces diverse offspring.

Which of the following statements about hormone regulation of the female reproductive cycle is true? A. LH and FSH are produced in the ovaries, and estradiol and progesterone are produced in the pituitary. B. Estradiol and progesterone secreted from the corpus luteum cause the myometrium to thicken. C. Progesterone is produced by the corpus luteum. D. Secretion of GnRH by the hypothalamus is inhibited by high levels of estradiol, but stimulated by low levels of estradiol.

C. Progesterone is produced by the corpus luteum.

How does the hypothalamus regulate the secretion of reproductive hormones in males? A. The hypothalamus releases FSH and LH at puberty by secreting of GnRH. FSH stimulates the Leydig cells in the testes and LH stimulates the Sertoli cells to synthesize and secrete testosterone. B. The hypothalamus releases FSH and LH at puberty by the secretion of GHRH. FSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone. C. The hypothalamus stimulates the release of FSH and LH at puberty by secreting of GnRH. FSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone. D. The hypothalamus releases TSH and LH at puberty by the secretion of GnRH. TSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone.

C. The hypothalamus stimulates the release of FSH and LH at puberty by secreting of GnRH. FSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone.

Explain what the mesoderm is and what it eventually differentiates into. A. The mesoderm, located on either side of the vertebrate neural tube, develops into connective tissues reorganized into groups of cells called somites, which develop into facial cartilage, ribs, and lungs. B. The mesoderm, located at the border of the neural plate and the non-neural ectoderm, develops into various connective tissues such as the ribs, lungs, segmental muscle, and the notochord, which forms the central axis of the animal body. C. The mesoderm, located on either side of the vertebrate neural tube, develops into various connective tissues reorganized into groups of cells called somites, which develop into ribs, lungs, segmental muscle, and the notochord. D. The mesoderm, located at the border of the neural plate and the non-neural ectoderm, develops into various connective tissues such as the facial cartilage, ribs, and lungs.

C. The mesoderm, located on either side of the vertebrate neural tube, develops into various connective tissues reorganized into groups of cells called somites, which develop into ribs, lungs, segmental muscle, and the notochord.

Discuss the positive feedback mechanisms by LH and FSH during the follicular and ovulation phase of the ovarian cycle. A. The stimulation of the anterior pituitary by GHRH secretes the hormones LH and FSH. Increasing amts stimulate many follicles in the ovary to start growing, but only one matures to release the egg. B. The stimulation of the anterior pituitary by GnRH secretes the hormones LH and TSH. Increasing amts stimulate many follicles in the ovary to start growing, but only one matures to release the egg. C. The stimulation of the anterior pituitary by GnRH triggers the secretion of the hormones LH and FSH. Increasing amts stimulate many follicles in the ovary to start growing, but only one matures to release the egg. D. The stimulation of the anterior pituitary by GHRH secretes the hormones LH and TSH. Increasing amts stimulate many follicles in the ovary to growing, but only one matures to release the egg.

C. The stimulation of the anterior pituitary by GnRH triggers the secretion of the hormones LH and FSH. Increasing amts stimulate many follicles in the ovary to start growing, but only one matures to release the egg.

What determines whether a zygote will undergo total or partial cleavage? A. Total cleavage takes place in eggs having a large amount of yolk, whereas partial cleavage occurs in eggs having very little or no yolk. B. Total cleavage occurs when eggs possess equal concentration of yolk at both poles, whereas partial cleavage occurs when the yolk is not equally distributed. C. Total cleavage takes place in eggs having little or no yolk, whereas partial cleavage occurs in eggs having a large amount of yolk. D. Total cleavage occurs when divisions of the blastomeres are separate, whereas partial cleavage occurs when blastomeres stay partially connected.

C. Total cleavage takes place in eggs having little or no yolk, whereas partial cleavage occurs in eggs having a large amount of yolk.

Which form of reproduction might be utilized by a sexually reproducing animal that has limited mobility? A. fragmentation B. budding C. hermaphroditism D. parthenogenesis

C. hermaphroditism

Which of the following best indicates that a female is ovulating? A. slight decrease in body temperature B. decrease in cervical volume C. more pliable cervical secretions D. change in breast size

C. more pliable cervical secretions

During childbirth, the hormone oxytocin causes contraction of the uterine wall muscles. As muscular contractions increase, more oxytocin is released from the pituitary, leading to more contractions. This is an example of which mechanism? A. end product inhibition B. negative feedback mechanism C. positive feedback mechanism D. feedback inhibition

C. positive feedback mechanism

After ovulation, increasing amounts of _____ cause the endometrium to start to thicken. A. fluid B. LH C. progesterone D. GnRH

C. progesterone

Which of the following does not describe axes of symmetry in animals? A. anterior-posterior B. dorsal-ventral C. upper-lower D. lateral-median

C. upper-lower

What are the three phases of embryonic development in chronological order? A. blastula → gastrula → cleavage B. blastula → cleavage → gastrula C. cleavage → gastrula → blastula D. cleavage → blastula → gastrula

D. cleavage → blastula → gastrula

Fertility is generally unaffected by_____. A. sexually transmitted diseases B. obstruction of reproductive tubes C. drug use D. genetic factors

D. genetic factors

Explain the similarities and differences in sexual response in males and females. A. Both males and females show specific arousal, but the sexual response differs in intensity and duration. B. Both males and females show specific arousal. In males, breathing rate and heart rate are increased. In females, there is a decrease in breathing rate and heart rate. C. Vasodilation occurs in both males and females, allowing blood to engorge erectile tissue in the nipples, clitoris, labia, vagina, and penis. In males, breathing rate and heart rate are increased. In females, there is a decrease in breathing rate and heart rate. D. Both males and females show an increase in heart rate, breathing rate, and blood pressure during phase one and phase two. However, sexual response differs in intensity and duration in males and females. Also, males show specific arousal, while females show non-specific arousal.

D. Both males and females show an increase in heart rate, breathing rate, and blood pressure during phase one and phase two. However, sexual response differs in intensity and duration in males and females. Also, males show specific arousal, while females show non-specific arousal.

Why are the diploid zygotes produced after fertilization of sperm cells produced by spermatogenesis not similar? A. Their chromosome numbers are not the same. B. The size of the sperm produced are different. C. Some sperm may have a tail, whereas others may not. D. Crossing over occurs during spermatogenesis.

D. Crossing over occurs during spermatogenesis.

What occurs in the procedure known as in vitro fertilization (IVF)? A. A sperm is injected into the egg externally. B. An egg is fertilized by the sperm internally in the oviduct. C. Eggs and sperm are combined externally and then implanted. D. Egg and sperm are combined externally and the resulting embryo is implanted.

D. Egg and sperm are combined externally and the resulting embryo is implanted.

Compare and contrast sex determination in birds and mammals. A. In mammals, sex is determined by XX (homozygous) in males and XY (heterozygous) in females, while in birds, sex is determined by ZZ (homozygous) in females and ZW (heterozygous) in males. B. In mammals, sex is determined by the presence of XX (homozygous) in males and XY (heterozygous) in females, while in birds, sex is determined by the presence of ZW (heterozygous) in females and ZZ (homozygous) in males. C. In mammals, sex is determined by the presence of XX (homozygous) in females and XY (heterozygous) in males, while in birds, sex is determined by the presence of ZZ (homozygous) in females and ZW (heterozygous) in males. D. In mammals, sex is determined by the presence of XX (homozygous) in females and XY (heterozygous) in males, while in birds, sex is determined by the presence of ZW (heterozygous) in females and ZZ (homozygous) in males.

D. In mammals, sex is determined by the presence of XX (homozygous) in females and XY (heterozygous) in males, while in birds, sex is determined by the presence of ZW (heterozygous) in females and ZZ (homozygous) in males.

What are the mechanisms that protect and nurture the embryo in oviparous animals? A. The hard leathery exterior of bird eggs and the hard calcium covering of reptile eggs provides protection to the growing embryo. Nourishment is provided by yolk in the eggs. B. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by endosperm in the eggs. C. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by placenta in the eggs. D. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by yolk in the eggs.

D. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by yolk in the eggs.