EXAM 4 review

Erection of the penis results from ________. A. a parasympathetic reflex that promotes release of nitric oxide B. a sympathetic activation of bulbospongiosus muscles C. parasympathetic activation of the bulbourethral glands D. dilation of the veins in the penis

A

Human chorionic gonadotropin (hCG) is at its highest levels ________. A. about 2 months after implantation during the 8th gestational week B. after copulation but before implantation C. at about the midpoint of pregnancy D. just before birth

A

Two alleles expressing exactly the same information for a trait are described as ________. A. homozygous B. heterozygous C. monogamous D. hemizygous

A

What does it mean when an allele is dominant? A. the allele hides the expression of the other allele B. healthy allele sometimes referred to as the wild type allele C. the stronger of two matched alleles D. the allele that is most frequently expressed in a given population

A

Which of the choices below is NOT a function of the vagina? A. serves as a passageway for the primary oocyte B. receives semen from the penis during sexual intercourse C. serves as a passageway for menstrual flow D. serves as the birth canal

A

Which statement below is true regarding independent assortment ? A. It is a significant source of genetic variation only during meiosis I. B. It only occurs in meiosis II. C. Its effects are significant in meiosis and in mitosis. D. It is a significant source of genetic variation that occurs in meiosis I and meiosis II.

A

Which structures receive the ovulated oocyte and provide a site for fertilization? A. uterine tubes B. Graafian follicles C. infundibula D. fimbriae

A

Neural tissue is formed by the ________. A. ectoderm B. epiderm C. endoderm D. mesoderm

A. ectoderm

How long is the secondary oocyte viable and capable of being fertilized after it is ovulated? A. 24-36 hours B. 12-24 hours* C. 7 days D. 36-72 hours

B

If a woman has just ended her menstrual phase, when is she most likely to ovulate? A. within the next 4-5 days B. in about 9-10 days C. in about 14 days D. in about 24 days

B

The placenta, a vitally important metabolic organ, is made up of a contribution from mother and fetus. Which portion is from the fetus? A. amnion B. chorion C. yolk sac D. umbilicus

B

Two alleles expressing exactly the same information for a trait are described as ________. A. monogamous B. homozygous C. hemizygous D. heterozygous

B

What is the role of the dartos and cremaster muscles of the male reproductive system? A. They are responsible for penile erection. B. They regulate the temperature of the testes. C. They contract to allow ejaculation. D. They contract to push sperm along the ductus deferens.

B

Which of the following female structures is homologous to the male scrotum? A. vagina B. labia majora C. clitoris D. labia minora

B

Albinism is a recessive trait. If one parent is heterozygous for albinism, and the other parent does not carry the allele, what is the probability that they will have a child with albinism? A. 100% B. 50% C. 0% D. 25%

C

If a person is homozygous for a particular trait this means ________. A. the person has two dominant alleles for the gene responsible for the trait B. the person will not have a recessive condition C. the person has two identical alleles for the gene responsible for the trait D. the person cannot pass on that trait

C

The diploid number of chromosomes in a human is 46. Therefore, the number of chromosomes in a primary spermatocyte or primary oocyte would be? A. 23 B. 38 C. 46 D. 92

C

The neonatal period refers to ________. A. the first trimester of pregnancy B. the first year after birth C. the first month after birth D. the last trimester of pregnancy

C

A couple whose blood types are AB (IAIB) and B (IBi) may have a child with which of the following blood types? A. AB only B. A or B only C. A, B, AB, or O D. A, B, or AB only

D

Gastrulation begins when a groove with raised edges called the ________ appears on the dorsal surface of the embryonic disc. A. spinal cord B. placenta C. notochord D. primitive streak

D

Recessive alleles are best defined as ________. A. a weakened or attenuated allele B. a deleterious or disease-causing allele C. the least frequently expressed allele in a given population D. an allele only expressed when the allele is homozygous

D

The correct sequence of preembryonic structures is ________. A. zygote, blastocyst, morula B. morula, zygote, blastocyst C. blastocyst, morula, zygote D. zygote, morula, blastocyst

D

The variation seen in ABO blood groups is due to ________. A. sex-linked inheritance B. incomplete dominance C. polygene inheritance D. multiple-allele inheritance

D

What process ensures the constancy of the chromosome number from one cell generation to the next? A. mitosis B. DNA synthesis C. cytokinesis D. meiosis

D

Which method of contraception is most reliable? A. morning-after pills B. rhythm method C. cervical cap D. vasectomy

D

Which statement below is true regarding independent assortment ? A. It is a significant source of genetic variation that occurs in meiosis I and meiosis II. B. Its effects are significant in meiosis and in mitosis. C. It only occurs in meiosis II. D. It is a significant source of genetic variation only during meiosis I.

D

T/ F Ovulation occurs near the end of the ovarian cycle.

FALSE

T/F A zygote is usually formed within the uterus.

FALSE

T/F Ovarian follicles contain mature eggs.

FALSE

T/F The Y chromosome contains far more genes than X chromosome?

FALSE

T/F The corpus luteum secretes progesterone only.

FALSE

T/F When genes are on the Y chromosomes, they are considered X-linked.

FALSE

T/F When it is cold, the scrotum is pulled away from the body

FALSE

Hereditary characteristics are transmitted to offspring by genes. True False

TRUE

T/ F It is necessary for the testes to be kept below body temperature for abundant, viable sperm formation.

TRUE

T/F Acrosomal enzymes trigger exocytosis of cortical granules in the zona reaction

TRUE

T/F By the end of the embryonic period, at 8 weeks, all the adult organ systems are recognizable.

TRUE

T/F In fetal circulation, one way in which blood bypasses the nonfunctional lungs is by way of the foramen ovale.

TRUE

T/F Male testicular functions are regulated by FSH and LH.

TRUE

T/F The "fluid-filled, hollow ball of cells" stage of development is the blastocyst

TRUE

T/F The period from fertilization through week eight is called the embryonic period.

TRUE

T/F The secretions of the bulbourethral glands neutralize traces of acidic urine in the urethra and serve as a lubricant during sexual intercourse.

TRUE

The same allele can have a different effect depending on which parent it comes from. Question 25 options: True False

TRUE

which of the below glads are responsible for producing 70% os semen volume?

The seminal vesicles

what normally triggers menstruation to occur?

drop in blood levels of estrogen and progesterone

T/ F when is cold, the scrotum is pulled away from the body?

false

T/F Premature infants often need to be placed on a ventilator because their undeveloped lungs produce excess surfactant

false

which of the following female structures is homologous to the male scrotum?

labia majora

what process ensures the constancy of the chromosomes number from one cell generation to the next?

meiosis

What is true about the similarity between a human egg and sperm cell?

they have the same number of chromosomes

T/F A scrotal muscle that contracts in response to cold environmental temperature in the cremaster?

true

T/F implantation begins six to seven days after ovulation?

true

T/F is it possible for a baby to have type O blood if neither parent is type "O"

true

T/F of the three germ layers, the mesoderm forms the most of the body parts?

true