m1 + 2 lab - cells, life cycles and proliferation

Question 1

what are the two cell differentiation types?

Answer 1

mitosis and meiosis

Question 2

what is mitosis?

Answer 2

cell division

Question 3

what is the purpose of mitosis?

Answer 3

replacement, repair, and growth

Question 4

what are the cell types in mitosis?

Answer 4

somatic cells (“soma” means body)

ex.) epithelium tissue
- muscle tissue
- connective tissue
- nerve tissue

Question 5

what tissues are amitotic?

Answer 5

• nerve cells
• cardiac muscle
• skeletal muscle

Question 6

what is the purpose of meiosis?

Answer 6

procreation

• genetic variation

Question 7

what cells are used in meiosis?

Answer 7

gametes/ sex cells

Question 8

what are outcomes that can happen if a cell does not go through the normal cell life cycle?

Answer 8

• cell dies
• cell turns cancerous

Question 9

what is the process of meiosis?

Answer 9

Meiotic Division 1
- begins with replicated DNA (4n)
- cell division occurs (each become 2n)
Meiotic Division 2
- each cell of 2n divides through a second cell division, producing 4 haploids (n or 23 chromosomes each)

Question 10

what is synapsis?

Answer 10

alignment of the homologous pairs at the cell equator – forming “tetrads”

in Prophase M1, maternal finds paternal

Question 11

what is a crossover (genetic recombination)?

Answer 11

one chromatid segment of a homologous chromosome exchanges positions with another chromatid (crossing over, forms chiasma)

chromatids break off, those ends join their corresponding (new) chromosomes

Question 12

what is spermatogenesis?

Answer 12

the process through which sperm cell production occurs

Question 13

where does spermatogenesis occur?

Answer 13

seminiferous tubules

Question 14

what is the name of the stem cell used in spermatogenesis?

Answer 14

spermatogonia

Question 15

pathway of spermatogenesis?

Answer 15

spermatids from spermatogonia mature in the Epididymis then spermiation occurs —> shedding of everything unnecessary

• begins at puberty
• ends at death

Question 16

what are the hormones used in spermatogenesis?

Answer 16

FSH and testosterone

Question 17

where does oogenesis occur?

Answer 17

ovary

Question 18

what is the name of the stem cell used in oogenesis?

Answer 18

oogonia

Question 19

pathway of oogenesis?

Answer 19

• begins at 8th month of gestation
• stops at Prophase of M1
• starts again at puberty w/ only a few at a time due to FSH and LH
• matures with the follicles
  process is not complete until it is fertilized

Question 20

what happens in Metaphase M2 of oogenesis during puberty?

Answer 20

the oocyte is ovulated

Question 21

how many sperm do males produce?

Answer 21

4 sperm, two X and two Y

Question 22

how many eggs do females produce?

Answer 22

only 1 viable egg, the other three sets of DNA are discarded

helps to increase survivability of the infant

Question 23

what does the hormone GnRH do to the anterior pituitary gland?

Answer 23

causing it to secrete FSH and LH - which target the ovaries

Question 24

what does follicle stimulating hormone (FSH) do?

Answer 24

oogenesis follicular development

Question 25

what does luteinizing hormone (LH) do?

Answer 25

stimulates ovulation hormone release - estrogen and progesterone

Question 26

what do interstitial cells do?

Answer 26

produce testosterone

Question 27

what do sustentacular (sertoli) cells do?

Answer 27

nourish and protect the sperm

Question 28

what happens to sperm in the epididymis during spermiation?

Answer 28

sperm: - matures - stored - reabsorbed

Question 29

what does capacitation do?

Answer 29

sperm need to mix with PSA (prostate specific antigen) to activate

Question 30

how many chromosomes do gametes contain?

Answer 30

23 chromosomes (not in pairs)

Question 31

what are the parts of a sperm cell?

Answer 31

head - acrosome --> enzymatic covering - nucleus --> n = 23 midpiece tail

Question 32

what do estrogen and progesterone control?

Answer 32

menses (menstruation)

Question 33

what is the ovarian cycle?

Answer 33

28 day cycle controlled by FSH and LH - produces secondary oocyte and estrogen/progesterone

Question 34

phases of the ovarian cycle?

Answer 34

follicular phase - day 1-13 ovulation phase - day 14 luteal phase - day 15-28

Question 35

what happens in the follicular phase (day 1-13)?

Answer 35

primordial follicles are activated ---> becoming primary follicles (cuboidal epithelium => secretes sex hormones) ---> becomes secondary follicles that release rising amounts of estrogen - helps endometrium redevelop follicle develops into large fluid filled Graffian Follicle (cuboidal cells surrounding oocyte are called Corona Radiata

Question 36

what happens in the ovulation phase (day 14)?

Answer 36

sudden increase in LH causes ovulation ---> expelling the oocyte into the peritoneum (may cause Mittelschmerz pain)

Question 37

what happens in the luteal phase (day 15-28)?

Answer 37

- after ovulation, left over granulosa cells form the Corpus Luteum (Yellow Body) - when Corpus Luteum forms ---> produce progesterone to maintain the endometrium

Question 38

what happens in the luteal phase if implantation occurs?

Answer 38

it will continue 90 days until the placenta takes over production

Question 39

what happens in the luteal phase if implantation does not occur?

Answer 39

the Corpus Luteum will degenerate in 10 days ---> leads to menses there will be a small scar called Corpus Albicans (White Body)

Question 40

phases in the uterine cycle?

Answer 40

1) menstrual phase 2) proliferative phase 3) secretory phase controlled by production of estrogens and progesterones

Question 41

what happens in the menstrual phase (days 1-5)?

Answer 41

menses -> menstruation endometrium sheds *** this occurs when progesterone levels drop to their lowest levels

Question 42

what happens in proliferative phase (day 6-14)?

Answer 42

- endometrium redevelops due to rising levels of estrogen - mucus is thin and watery to allow passage of sperm into the uterus - day 14 - ovulation occurs due to LH

Question 43

what happens in the secretory phase (day 15-28)?

Answer 43

- endometrium prepares for implantation of egg - levels of progesterone rise => functional layer becomes mucosal layer, acts as a mucus plug in Os of cervix

Question 44

what system causes erection/arousal?

Answer 44

parasympathetic system

Question 45

orgasm is caused by:

Answer 45

sympathetic system

Question 46

ejaculation occurs by:

Answer 46

bulbospongiosus muscle contractions

Question 47

fertilization occurs where in the fallopian tube?

Answer 47

ampulla

Question 48

a blastocyst:

Answer 48

is implanted into the endometrium in about 7 days - after implantation, production of HCG occurs

Question 49

HCG:

Answer 49

Human Chorionic Gonadotropin - indicates pregnancy - maintains Corpus Luteum

Question 50

what happens in the embryonic stage?

Answer 50

- placenta attaches to the endometrium - amniotic sac -embryo develops in the first 8 weeks of gestation

Question 51

what does the placenta provide?

Answer 51

- location of nutrient diffusion, waste removal and oxygenation of the fetal blood - produces HCG and then progesterone (which maintains the pregnancy)