Reproduction and Development

Not form a placenta

A blastocyst without a trophoblast would

The lack of genetic variability puts them at risk in changing environments

A disadvantage of asexual reproduction is that

Cleavage

A fertilized egg undergoes cell division without further growth in the process called

Lower temperature

A functional advantage of having human testes in the scrotum rather than in the abdomen is

hCG; trophoblast

A pregnancy test is based on the production of ___ by the ____.

Males produce many more sperm than females produce eggs

A single egg is evolutionarily more precious than a single sperm because

Increase the evolutionary fitness of the species

According to the grandmother hypothesis, human women live beyond their reproductive years to

Differentiates into the corpus luteum

After ovulation, the ruptured follicle

B. Since an unborn infant gets priority on blood nutrient pools, pregnancy during famine will likely be fatal for both mother and offspring; this mechanism reduces this risk and increases survival.

Although estrogen is primarily produced by ovaries, it is also produced by the adrenal glands and in fat tissue. Loss of the normal amount of fat lowers the level of estrogen so that the menstrual cycle and ovulation stops. Female Olympic athletes who train severely often shut off their cycles. What would be a reasonable evolutionary cause of this shutdown? A. This mechanism shifts use of energy from reproduction to life activities for staying alive. B. Since an unborn infant gets priority on blood nutrient pools, pregnancy during famine will likely be fatal for both mother and offspring; this mechanism reduces this risk and increases survival. C. The adrenal glands have evolved to produce fight-or-flight responses and natural selection has shifted them to this function and away from estrogen. D. Less food would result in less hormone production.

C. The cycle requires minimal threshold of estrogen and although the ovaries produce their regular levels, the loss of body fat would lower the estrogen level to below the threshold, thus shutting down the menstrual cycle.

Although estrogen is primarily produced by ovaries, it is also produced by the adrenal glands and in fat tissue. Young female athletes who train strenuously often find that their menstrual cycle shuts down. What would be a reasonable direct cause of this shutdown? A. The increased need for ATP for the muscle cells deprives ATP for ovaries. B. The increased use of ATP for muscles deprives ATP needed by the brain where the hypothalamus and pituitary control the menstrual cycle. C. The cycle requires minimal threshold of estrogen and although the ovaries produce their regular levels, the loss of body fat would lower the estrogen level to below the threshold, thus shutting down the menstrual cycle. D. Physical trauma to the ovaries themselves would shut down their estrogen production.

Fallopian tube

Another name for the oviduct is the

Small levels of estrogens are produced by the adrenal glands and fat tissue; with the lack of testosterone, a body develops along female patterns.

Castrating prepubescent bulls causes them to grow in female proportions because

14th day

During a 28-day uterine cycle, ovulation usually occurs on the

Fourth

During the ____ month, the fetal heartbeat is first loud enough to be heard by a physician with a stethoscope.

Blastula

During the formation of an embryo, a hollow sphere of cells with a fluid-filled cavity inside is termed a

No cell growth

Early cell division leading to the morula is characterized by rapid cell division and

FSH and LH

Female birth control pills act by inhibiting the production of

Abdominal cavity

Fertilization in humans normally occurs in the

The oviduct

Fertilization in humans occurs in which of the following structures?

Lanugo

From months 5 to 7, a fetus is covered in a fine down called

When the first sperm fuses with the egg membrane, it causes the membrane to depolarize and also separates the fertilization membrane and this gap forms a barrier to any other sperm

Generally only one sperm fertilizes an egg because

Half the

Haploid cells have ________ number of chromosomes as diploid cells.

Enzymes in the acrosome dissolve the zona pellucida

How does a sperm penetrate an egg?

Small tubules lined with developing sperm.

If we cut a cross-section through the testes, we would see

Second week

Implantation occurs during the

Yolk sac

In human development, the ______ is the site of early blood cell formation for the fetus.

Egg is fertilized

In human females meiosis is completed when the

Mitosis

In humans, males have a continuous supply of germ line cells because those cells regularly go through

Pituitary

In the human female, estrogen and progesterone exert feedback control over the

28 days

In the human female, the uterine cycle is an average

Seminiferous tubules

In the human male, sperm cells are produced in the

Urethra

In the human male, the tube used to carry both sperm and urine is the

Controls production of testosterone

LH is an abbreviation for luteinizing hormone, which is present in both males and females. In the male, LH

Corpus luteum to produce progesterone

LH stimulates the

interstitial cells; testosterone

LH stimulates the ______ of the testis to produce ______.

Men produce new sperm every day, while women are born with their life's allotment of eggs

Men can produce healthy sperm longer than women can produce healthy eggs because

Progesterone and estrogen levels are both declining

Menstruation begins because

prolactin; anterior pituitary

Milk production is triggered in breasts following several days of ____ production by the ____.

Protects the first trimester fetus from toxins

Morning sickness may be an evolutionary advantage because it

Inductive signals

Morphogens are examples of

They have different gene expression patterns

Nerve cells and skin cells from an individual are different functionally and structurally. These two types of cells from the same person are different because

The developing embryo implants itself in the endometrium

Pregnancy occurs when

HCG

Pregnancy tests detect the presence of ______ in the urine.

Testosterone

Secondary sexual characteristics in the male are directly maintained by the hormone

Prostaglandins

Seminal fluid contains _____, chemicals that cause the uterus to contract.

Maintenance of genetic variability

Sexual reproduction is necessary for

Epididymis

Sperm mature within the

Chorion

The _____ develops into the fetal portion of the placenta.

Chorion

The _____ is responsible for gas exchange in the egg of a chicken.

Yolk sac

The _______ provides nourishment for the embryo during chick development.

Expulsion of the placenta and membranes.

The afterbirth refers to the

Are analogous to the umbilical blood vessels in humans.

The allantoic blood vessels

Blastula

The blastocoel is formed during the _____ stage of development.

Fructose sugar in the surrounding seminal fluids added by the seminal vesicles.

The energy source for sperm to swim comes from

First

The fetus is most sensitive to the detrimental effects of alcohol during the ________ trimester.

Scrotum

The glans clitoris in the female is homologous to the ____ in the male.

oxytocin; hypothalamus

The hormone ____ from the ____ causes mammary lobules in the breast to contract, causing milk to flow.

Endometrium

The lining of the uterus that is discharged during the menstrual phase is the

E. fimbriae

The male reproductive system includes all EXCEPT which of the following? A. testes B. epididymis C. penis D. prostate E. fimbriae

B. interstitial cells

The male sex hormones are secreted by which of the following? A. spermatids B. interstitial cells C. vas deferens D. prostate

Placenta

The organ that exchanges molecules between fetal and maternal blood is the

Both fetal and maternal tissue.

The placenta develops from

Yolk sac

The sac that surrounds the fetus and usually ruptures just before childbirth is the

Third or fourth

The sex of the fetus can be first determined in the ______ month of development.

Vesicular (Graafian) follicle

The structure from which an egg is released during ovulation is called a(n)

Seminiferous Tubules → Epididymis → Vas Deferens → Urethra

Trace the correct path of the sperm during ejaculation.

Vagina → Cervix → Uterus → Oviduct

Trace the path of the sperm through the female reproductive tract.

Testosterone and Estrogen

What hormones influence the development of the secondary sexual characteristics of female?

Support and regulate the spermatogenic cells

What is the function of the Sertoli cells in the male reproductive tract?

vas deferens—carries urine

Which association concerning structures in the human male is incorrect? A. testes—produce sperm B. vas deferens—carries urine C. prostate gland—seminal fluid D. urethra—conducts sperm E. seminal vesicle—seminal fluid

A. oxytocin

Which of the following hormones causes the uterus to contract? A. oxytocin B. estrogen C. progesterone D. testosterone E. prolactin

B. acrosome

Which of the following is NOT a barrier to the sperm entering the egg? A. zona pellucida B. acrosome C. follicle cells D. the egg's plasma membrane

B. formation of the germ line cells

Which of the following is NOT a characteristic of childhood development? A. development of speech B. formation of the germ line cells C. increasing brain weight D. rapid growth

B. gastrulation

Which of the following is NOT a contraceptive? A. barriers that prevent sperm from entering the uterus B. gastrulation C. sterilization D. hormones that suppress ovulation

D. production of fat

Which of the following is NOT associated with the first trimester of fetal development? A. development of the sex organs B. rapid differentiation into the three tissue layers C. production of germ line cells D. production of fat

E. LH

Which of the following is responsible for controlling the production of male sex hormones? A. testosterone B. progesterone C. GnRH D. FSH E. LH

B. genetic recombination

Which of the following occurs during sexual reproduction but NOT during asexual reproduction? A. production of offspring B. genetic recombination C. cell division D. parthenogenesis

A. amniotic fluid

Which of the following serves as an insulator for the embryo? A. amniotic fluid B. allantois C. chorion D. primitive streak E. yolk sac

D. They are made of differentiated cells.

Which of the following statements about the three embryonic tissue layers is true? A. They are present in the morula. B. The cells of one layer are genetically different from the cells of another layer. C. All three layers develop into the same set of tissues. D. They are made of differentiated cells.

D. A surge of FSH promotes ovulation.

Which of the following statements is incorrect? A. The follicles in the ovary produce estrogen. B. The corpus luteum produces progesterone. C. placenta produces both estrogen & progesterone. D. A surge of FSH promotes ovulation.

C. Birth control pills have other health benefits in addition to preventing pregnancy.

Which statement about contraceptives is true? A. It is not necessary to follow the directions for taking the Pill for it to be 100 percent effective. B. Condoms prevent the transmission of sexually transmitted diseases but do not prevent pregnancy. C. Birth control pills have other health benefits in addition to preventing pregnancy. D. All contraceptives prevent the transmission of sexually transmitted diseases.

D. Maternal and fetal blood mix with each other.

Which statement is NOT correct about the placenta? A. Oxygenated blood flows to the fetus via the umbilical vein. B. Fetal blood flows to the placenta via the umbilical artery. C. Oxygen and nutrients go to the fetus from the maternal circulatory system. D. Maternal and fetal blood mix with each other.

Pituitary

Which structure in humans produces FSH?

The pituitary detects high levels of testosterone in the bloodstream and reduces FSH and LH.

Why do testes shrink when male athletes take synthetic steroid testosterone hormones?