Chapter 4 - Reproduction & Development

Question 1

Gonadotropin Releasing Hormone (GnRH)

Answer 1

released from hypothalamus, signals anterior pituitary to release gonadotropins: LH and FSH

Question 2

Luteinizing Hormone (LH)

Answer 2

travel to gonads

Question 3

Follicle Stimulating Hormone (FSH)

Answer 3

travel to gonads

Question 4

Spermatozoa

Answer 4

male germ cells

Question 5

Ova

Answer 5

female germ cells

Question 6

Spermatogenesis

Answer 6

production of sperm, requires temp lower than that of body temperature

Question 7

Seminiferous Tubules

Answer 7

convoluted tubules that contain spermatogenic cells

Question 8

Leydig Cells

Answer 8

interstitial cells that synthesize testosterone from cholesterol

Question 9

Sertoli Cell

Answer 9

testosterone binds to a specific receptor and is converted to a compound called dihydrotestosterone (dHT)

Question 10

Spermatogonia

Answer 10

they have 46 chromosomes, reside towards basement membrane, divide by mitosis

Question 11

Inhibin

Answer 11

acts as a negative modulator of the anterior pituitary

Question 12

What happens when testosterone is too high?

Answer 12

Feedback mechanism will decrease the levels of LH

Question 13

What happens when levels of dihydrotestosterone are too high?

Answer 13

increase in inhibin synthesis, which results in a decrease in levels of FSH

Question 14

Secondary Oocyte

Answer 14

has 23 chromosomes

Question 15

Follicular Phase

Answer 15

developing time period, lasts up to 14th day of woman’s monthly cycle

Question 16

Zona Pellucida

Answer 16

membrane surrounding the primary oocyte

Question 17

Granulosa cells

Answer 17

analogous to Sertoli cells in male

Question 18

Theca cells

Answer 18

analogous to Leydig cells in male, convert cholesterol to testosterone—diffuses into follicle cells where it’s converted to estrogen

Question 19

Antrum

Answer 19

formed by fluid building up in primary follicle

Question 20

LH Surge

Answer 20

this surge causes the primary oocyte to undergo first meiotic division

Question 21

Corpus Luteum

Answer 21

produce estrogen and progesterone

Question 22

Luteal Phase

Answer 22

point of ovulation (about 14th day) until the beginning of menstrual flow

Question 23

Chorionic Gonadotropin (CG)

Answer 23

synthesized by placenta, stimulates the corpus luteum to make estrogen and progesterone—one of the best pregnancy tests is to see if CG is present in blood

Question 24

Coelom

Answer 24

body cavity, divided into upper thoracic cavity and lower abdominal cavity

Question 25

What are the stages of development?

Answer 25

1. Fertilization 2. Cleavage (of zygote) 3. Gastrulation (formation of 3 germ layers) 4. Neurulation - formation of nervous system 5. Neural Crest Formation 6. Organogenesis

Question 26

Blastomeres

Answer 26

the individual cells involved in growth/cleavage of zygote in half. cleaves 5 times to get a morula (32 cells)

Question 27

Morula

Answer 27

a small, solid ball of cells

Question 28

Gastrula

Answer 28

means gastrulation has already taken place

Question 29

What are the 3 cell layers during development?

Answer 29

Ectoderm, mesoderm, and endoderm

Question 30

Ectoderm

Answer 30

developmental fate, differentiates into skin, lens of eye, brain, nervous system

Question 31

Mesoderm

Answer 31

notochord, heart, skeleton, muscle, and outer coverings of internal organs, and reproductive organs

Question 32

Endoderm

Answer 32

inner lining of digestive tract and respiratory tract, major glands of body like liver and pancrease

Question 33

What is the neural plate?

Answer 33

mass of ectodermal cells superior to notochord, plate will begin to fold in on itself and form the neural groove, edges of plate fuse and become neural tube