reproduction

Question 1

what prevents polyspermy by destroying the sperm receptors

Answer 1

zips (zonal inhibiting protein)

Question 2

which stage is the true moment of fertilization

Answer 2

once the chromosomes of the male and female pronuclei are united

Question 3

what is the definition of cleavage

Answer 3

a period of fairly rapid mitotic divisions of the zygote without intervening growth

Question 4

how many days after ovulation does the conceptus implant on the uterine wall

Answer 4

six to seven

Question 5

the corpus luteum is formed at the site of

Answer 5

ovulation

Question 6

which structures form the placenta

Answer 6

chorionic villi and decidua basalis

Question 7

when a woman’s water breaks just before delivery it is the —– that ruptures

Answer 7

amnion

Question 8

glandular organ most likely arise from the —– as they share secretory properties with the gut

Answer 8

endoderm

Question 9

why is it necessary to send some blood through the pulmonary circuit in a fetus?

Answer 9

the fetal lung tissue requires oxygen for development and growth.

Question 10

what stimulus triggers parturition?

Answer 10

increased estrogen secretion from the uterus.
increased oxytocin secretion from the mother’s posterior pituitary gland.
increased fetal cortisol secretion.

Question 11

what stimulates baby to take their first breath?

Answer 11

increased carbon dioxide in the blood.

Question 12

breast feeding provides several advantages to newborns. for example ———–

Answer 12

breast milk, especially colostrum, is rich in maternal antibodies.
the fat in breast milk is fully absorbed be the infant.
breast milk contains antimicrobial molecules

Question 13

during development the conceptus is called ————– from fertilization through to week 8 and ———– from week 9 to birth.

Answer 13

embryo

fetus

Question 14

————– is the process by which sperm become capable of penetrating oocyte.

Answer 14

capacitation

Question 15

how many sperm are required to break through outer corona radiata of the oocyte for fertilization to occur?

Answer 15

hundreds

Question 16

trace the path of sperm from spermatogenesis to ejaculation. name the glands and their main products.

Answer 16

testes, epididymis urethra, ductus deferens, prostate gland, seminal vesicle and penis.

Question 17

outline temperature regulation mechanisms within the scrotum

Answer 17

cremaster muscle - lowers and raises testes inside the abdomen.
Dartos muscle- expands or contracts to wrinkle the scrotal skin.
pampiniform plexus- acts as a heat exchange, cooling blood for adjacent arteries.

Question 18

explain spermatogenesis? What is spermiogenesis?

Answer 18

the production or development of mature spermatozoa. Spermiogenesis is the final stage of spermatogenesis, which sees the maturation of spermatids into mature, motile spermatozoa.

Question 19

when do the testes descend?

Answer 19

Testes descend in 7th month. testosterone promotes descent and remains high in infants for 1 month after birth. part of the peritoneum travels down into the scrotal sac and separates from the peritoneum. this forms tunica vaginalis. The tough fibrous cord called the gubernaculum attaches to testes and guides scrotum down. gubernaculum doesn’t change length but guides testes together through the inguinal canal.

Question 20

outline the HPG axis with respect to the regulation of spermatogenesis. What hormones are involved?

Answer 20

interactions between hypothalamus, anterior pituitary and the testes.
Brain- testicular axis
1. GnRH stimulates the release of GSH and LH commencing at puberty.
2. FSH and LH released.
3. FSH stimulates spermatogenesis by indirectly stimulating ABP (androgen binding protein) release from sustenticular cells or Sertoli Cells allowing testosterone to bind and maintain high concentrations int he seminiferous lumen.
4. LH acts on the interstitial cells of Leydig to produce testosterone.
5. testosterone released into blood. concentrated in testes for spermatogenesis. (essential for meiosis and mitosis and FSH needed for spermatid remodeling.

Question 21

Stages of male sexual response. What nervous system is dominating?

Answer 21

The sexual response cycle has four phases: excitement, plateau, orgasm, and resolution. autonomic nervous system.

Question 22

Describe the phases of the ovarian cycle

Answer 22

20 to 45 days in length (typically 28 days) follicular stage: before ovulation stage 1 to 6 follicular phase, stage 7 ovulation, stage 8 luteal phase (luteal phase is after ovulation and always constant)

Question 23

describe follicular phase

Answer 23

primordial follicle becomes primary follicle when surrounding cell become cuboidal in shape when more than 1 layer forms around the oocyte the follicle is referred to as granulosa cell. connective tissue called theca folliculi forms around the granulosa later together these cell layers produce estrogen zona pellucida production by granulosa cells signals increasing maturity of the follicle becomes late secondary follicle Antrum (clear fluid) bulges. oocyte completes meiosis 1 and becomes a secondary oocyte arrested in meta phase 2.

Question 24

describe ovulation

Answer 24

bulging follicle ruptures releasing the secondary oocyte into the peritoneal cavity. The oocyte is quickly swept into the Fallopian tubes where fertilization may or may not take place the rise in LH has several effects: signals primary oocyte to complete meiosis 1 to from a secondary oocyte arrested in metaphase 2. Releases enzymes that weakens he ovarian wall near the bulging follicle.

Question 25

phases of the Menstrual cycle

Answer 25

menstrual phase: proliferative phase : The proliferative phase is the second phase of the uterine cycle when estrogen causes the lining of the uterus to grow, or proliferate, secretory phaseThe next phase of the menstrual cycle is the luteal or secretory phase. This phase always occurs from day 14 to day 28 of the cycle. Progesterone stimulated by LH is the dominant hormone during this phase to prepare the corpus luteum and the endometrium for possible fertilized ovum implantation.

Question 26

24. The order of the ducts through which sperm must travel during ejaculation: a) Seminiferous tubules, epididymis, ductus deferens, urethra b) Seminal vesicles, ductus deferens, epididymis, urethra c) Scrotal sac, epididymis, seminal vesicles, prostate, urethra d) Seminiferous tubules, ductus deferens, epididymis, urethra

Answer 26

a) Seminiferous tubules, epididymis, ductus deferens, urethra

Question 27

25. The skeletal muscle layer that can alter the position of the scrotal sac is called______ a) Dartos muscle b) Tunica albuginea c) Cremaster muscle d) Both a) and c) are correct

Answer 27

c) Cremaster muscle

Question 28

26. In the male sexual response, erection is controlled by _____________ a) Branches of the sympathetic nervous system which cause vasodilation of arterioles b) Somatic nervous system which cause vasodilation of veins c) Branches of the parasympathetic nervous system which cause vasodilation arterioles d) Branches of the sympathetic nervous system which case vasoconstriction of arterioles

Answer 28

c) Branches of the parasympathetic nervous system which cause vasodilation arterioles

Question 29

27. In spermatogenesis, which cells of the testes produce androgen-binding protein? a) Sustentacular cell (sustentocytes) b) Interstitial endocrine cells of Leydig c) Spermatogonia d) Spermatocytes

Answer 29

a) Sustentacular cell (sustentocytes)

Question 30

``` 28. In a typical negative feedback loop, testosterone produced by the testes inhibits the release of which hormone(s)? a) Gonadotropin releasing hormone (GnRH) b) Follicle stimulating hormone c) Luteinizing hormone d) All of the above ```

Answer 30

d) All of the above

Question 31

29. Typically, fertilization of the oocyte occurs in the______________ a) Peritoneal cavity b) Cervical canal c) Uterus d) Uterine (Fallopian) tubes

Answer 31

d) Uterine (Fallopian) tubes

Question 32

30. Which is not an effect of luteinizing hormone surge? a) Promotes rupture of the mature follicle wall at ovulation b) Induces the primary oocyte to enter into stage 2 of meiosis c) Negative feedback to anterior pituitary d) Transforms the ruptured follicle, after ovulation, into the corpus luteum

Answer 32

c) Negative feedback to anterior pituitary

Question 33

``` 31. The secretory phase of the uterine cycle corresponds with the _______phase of the ovarian cycle a) Follicular b) Ovulation c) Proliferative d) Luteal ```

Answer 33

d) Luteal

Question 34

32. The cells of the ovary that produce estrogen (oestrogen) are called______ a) Granulosa cells b) Thecal cells c) Corona radiata d) Oocytes

Answer 34

a) Granulosa cells

Question 35

33. The blastocyst is composed of: a) Two blastomeres b) Embryoblast c) Trophoblast d) Both b) and c)

Answer 35

d) Both b) and c)

Question 36

34. The trophoblast cells transform into _________ a) Foetal portion of the placenta b) Yolk sac c) Amnion d) Embryo

Answer 36

a) Foetal portion of the placenta

Question 37

35. The maternal portion of the placenta is termed a) Yolk sac b) Amnion c) Decidua basalis d) Endometrium

Answer 37

c) Decidua basalis

Question 38

``` 1. Where is 30% of the seminal fluid in? Vas deferens Prostate gland Seminal vesicles Epididymis ```

Answer 38

Prostate gland

Question 39

``` 2.Which of these are a mechanism for regulating temperature for spermatogenesis? Dartos smooth muscle Cremaster skeletal muscle Pampiniform plexus All of the above ```

Answer 39

All of the above

Question 40

``` 3.Which of these produces testosterone? Interstitial cells of Leydig Sustentacular cells Sustenocytes Trophoblastic cells ```

Answer 40

Interstitial cells of Leydig

Question 41

``` 4.Which hormone is used in pregnancy tests? Progesterone Estrogen Human chorionic gonadotropin Luteinizing hormone ```

Answer 41

Human chorionic gonadotropin

Question 42

``` 5.Which is the maternal portion of the placenta? Decidua capsularis Decidua basalis Chorion Yolk sac ```

Answer 42

Decidua basalis

Question 43

``` 6.Which of these does the corpus luteum not secrete? Inhibin Luteinizing hormone Progesterone Estrogens ```

Answer 43

Luteinizing hormone

Question 44

``` 7.Which of these is the correct order of the female sexual response? Excitement, Plateau, Orgasm, Resolution Excitement, Orgasm, Plateau, Resolution Orgasm, Excitement, Plateau, Resolution Orgasm, Plateau, Excitement, Resolution ```

Answer 44

Excitement, Plateau, Orgasm, Resolutio

Question 45

``` 8.Which of these produces ABP? Interstitial cells of Leydig Sustentacular cells Trophoblastic cells Anterior pituitary ```

Answer 45

Sustentacular cells

Question 46

``` 9.Which structure in the penis fills with blood during an erection? Corpora cavernosa Corpus spongiosum Penile urethra Prostatic urethra ```

Answer 46

Corpora cavernosa

Question 47

10. Which statement is untrue? The ovum secreted the chemoattractant allurin Sperms can survive for 48 hours The ovum must be fertilised within 48 hours Enzymes in the acrosome allow the penetration of the corona radiata and the zona pellucida

Answer 47

The ovum must be fertilised within 48 hours

Question 48

``` 11. What is not a feature of the LH surge during ovulation? Causes the release of enzymes Caused systemic inflammation Lasts 2 minutes Occurs 24 hours before ovulation ```

Answer 48

Caused systemic inflammation

Question 49

``` 12. Which one of the follicles contains squamous epithelium? Primordial follicle Primary follicle Secondary follicle Vesicular follicle ```

Answer 49

Primordial follicle

Question 50

``` 13. What do theca cells secrete? Oestrogen Androgens Testosterone Progesterone ```

Answer 50

Androgens

Question 51

14.In males, the follicle stimulating hormone acts… On Interstitial Cells of Leydig to release Testosterone In a tropic manner to promote secondary sex characteristics On Sustentacular Cells By stimulating the contraction of the vas deferens, releasing sperm into the ejaculatory duct

Answer 51

On Sustentacular Cells

Question 52

``` 16.After fertilisation the zygote goes through a rapid period of cell division called: Organogenesis Blastulation Cleavage Implantation ```

Answer 52

Cleavage

Question 53

15.Which statement about maternal hormones during pregnancy is accurate? Oestrogen levels decline throughout gestation Progesterone levels decline throughout gestation hCG levels remain stable throughout gestation Oestrogen levels increase throughout gestation

Answer 53

Oestrogen levels increase throughout gestation

Question 54

1. Which hormone acts on the kidney to increase water reabsorption? a) Aldosterone e c) Growth hormone d) Thyroid stimulating hormone

Answer 54

b) Antidiuretic hormon

Question 55

2. The anterior pituitary gland secretes all the following hormones except….. a. Prolactin b. Antidiuretic hormone c. Adrenocorticotropic hormone d. Follicle stimulating hormone

Answer 55

b. Antidiuretic hormone

Question 56

3. Which statement is TRUE regarding steroid hormones? a. Steroid hormones are hydrophilic b. Steroid hormones amplify their effects via a second messenger system c. Steroid hormones produce their effects by binding to DNA d. Steroid hormones involve activation of cAMP

Answer 56

c. Steroid hormones produce their effects by binding to DNA

Question 57

4. Alpha (a) and Beta (B) cells are found in which endocrine organ? a. Thyroid gland b. Parathyroid gland c. Adrenal gland d. Pancreas

Answer 57

d. Pancreas

Question 58

5. Which of the following is NOT involved in the synthesis of Thyroid hormone (T3 & T4) a. Thyroglobulin b. Iodine c. Tyrosine d. Calcitonin

Answer 58

d. Calcitonin

Question 59

6. Inhibiting and releasing hormones are synthesized by… a. Hypothalamic neurons b. Hypophyseal portal system c. Infundibulum d. Neurohypophysis

Answer 59

a. Hypothalamic neurons

Question 60

7. Acromegaly is the result of hypersecretion of which hormone…….. a. Growth hormone b. Parathyroid hormone c. Cortisol d. Oxytocin

Answer 60

a. Growth hormone

Question 61

8. A deficiency in iodine may result in……. a. Hypothyroidism b. Hyperthyroidism c. Gigantism d. Addison’s diseas

Answer 61

a. Hypothyroidism

Question 62

9. The release of Parathyroid hormone (PTH) acts to regulate blood calcium via…. a. Inhibiting osteoclasts b. Enhancing calcium reabsorption in the kidney c. Inhibition of vitamin D d. None of the above

Answer 62

b. Enhancing calcium reabsorption in the kidney

Question 63

``` 10. An increase in the level of blood K+ levels may trigger the release of…. a. Aldosterone b. Atrial natriuretic peptide c. Cortisol d. Renin ```

Answer 63

a. Aldosterone

Question 64

24. The order of the ducts through which sperm must travel during ejaculation: a) Seminiferous tubules, epididymis, ductus deferens, urethra b) Seminal vesicles, ductus deferens, epididymis, urethra c) Scrotal sac, epididymis, seminal vesicles, prostate, urethra d) Seminiferous tubules, ductus deferens, epididymis, urethra

Answer 64

a) Seminiferous tubules, epididymis, ductus deferens, urethra

Question 65

25. The skeletal muscle layer that can alter the position of the scrotal sac is called______ a) Dartos muscle b) Tunica albuginea c) Cremaster muscle d) Both a) and c) are correct

Answer 65

c) Cremaster muscle

Question 66

26. In the male sexual response, erection is controlled by _____________ a) Branches of the sympathetic nervous system which cause vasodilation of arterioles b) Somatic nervous system which cause vasodilation of veins c) Branches of the parasympathetic nervous system which cause vasodilation arterioles d) Branches of the sympathetic nervous system which case vasoconstriction of arterioles

Answer 66

c) Branches of the parasympathetic nervous system which cause vasodilation arterioles

Question 67

27. In spermatogenesis, which cells of the testes produce androgen-binding protein? a) Sustentacular cell (sustentocytes) b) Interstitial endocrine cells of Leydig c) Spermatogonia d) Spermatocytes

Answer 67

a) Sustentacular cell (sustentocyte

Question 68

``` 28. In a typical negative feedback loop, testosterone produced by the testes inhibits the release of which hormone(s)? a) Gonadotropin releasing hormone (GnRH) b) Follicle stimulating hormone c) Luteinizing hormone d) All of the above ```

Answer 68

d) All of the above

Question 69

29. Typically, fertilization of the oocyte occurs in the______________ a) Peritoneal cavity b) Cervical canal c) Uterus d) Uterine (Fallopian) tubes

Answer 69

d) Uterine (Fallopian) tubes

Question 70

30. Which is not an effect of luteinizing hormone surge? a) Promotes rupture of the mature follicle wall at ovulation b) Induces the primary oocyte to enter into stage 2 of meiosis c) Negative feedback to anterior pituitary d) Transforms the ruptured follicle, after ovulation, into the corpus luteum

Answer 70

c) Uterus

Question 71

``` 31. The secretory phase of the uterine cycle corresponds with the _______phase of the ovarian cycle a) Follicular b) Ovulation c) Proliferative d) Luteal ```

Answer 71

d) Luteal

Question 72

32. The cells of the ovary that produce estrogen (oestrogen) are called______ a) Granulosa cells b) Thecal cells c) Corona radiata d) Oocytes

Answer 72

a) Granulosa cells

Question 73

33. The blastocyst is composed of: a) Two blastomeres b) Embryoblast c) Trophoblast d) Both b) and c)

Answer 73

d) Both b) and c)

Question 74

34. The trophoblast cells transform into _________ a) Foetal portion of the placenta b) Yolk sac c) Amnion d) Embryo

Answer 74

a) Foetal portion of the placenta

Question 75

35. The maternal portion of the placenta is termed a) Yolk sac b) Amnion c) Decidua basalis d) Endometrium

Answer 75

c) Decidua basalis