Reproduction (CH2)

Question 1

What stages are contained in interphase?

Answer 1

G1, S, G2

Question 2

G1:

Answer 2

-Cells create organelles for energy and protein function.
-Cell size increases

Question 3

S:

Answer 3

-DNA is replicated
-Chromatids (strands of DNA) are held together by centromere

Question 4

G2:

Answer 4

-More cell growth
-Organelles replicated in preparation for mitosis

Question 5

G0:

Answer 5

Cell performs function with no intentions of dividing

Question 6

Cyclins

Answer 6

Bind to cyclin-dependent kinases (CDK)

Question 7

Why do cyclins bind to CDH?

Answer 7

To activate transcription factors for the next stage of the cell cycle

Question 8

In what cells does mitosis occur?

Answer 8

Somatic cells

Question 9

Mitosis: Prophase

Answer 9

-Chromosomes condense
-Nuclear membrane dissolves
-Nucleoli dissapear
-Spindle apparatus forms
-Kinetochore of each chromosome is contacted by spindle fiber

Question 10

Mitosis: Metaphase

Answer 10

-Chromosomes line up on metaphase plate

Question 11

Mitosis: Anaphase

Answer 11

-Sister chromatids are separated and pulled to opposite poles

Question 12

Mitosis: Telophase

Answer 12

-Nuclear membrane reforms
-Spindle apparatus dissappears

Question 13

Cytokinesis (M Phase)

Answer 13

-Cytosol and organelles are split between two daughter cells

Question 14

In what type of cells does meiosis occur in?

Answer 14

Germ cells (germatocytes)

Question 15

What is produced by mitosis?

Answer 15

2 genetically identical daughter cells

Question 16

What is produced by meiosis?

Answer 16

4 nonidentical haploid sex cells (gametes)

Question 17

How many rounds of replication are in meiosis?

Answer 17

1

Question 18

How many rounds of division are in meiosis?

Answer 18

2

Question 19

In meiosis 1, what are separated?

Answer 19

Homologous pairs

Question 20

What are homologous pairs?

Answer 20

Chromosomes that are given the same number, but are opposite parental origin (i.e. chromosome 13 from mom and chromosome 13 from dad)

Question 21

Meiosis: Prophase 1

Answer 21

Same as mitosis but with some differences:
-Homologous pairs come together and intertwine (AKA synapsis)
-The tetrad (4) of chromatids perform crossing over

Question 22

Crossing over accounts for which of Mendel’s laws?

Answer 22

Mendel’s second law (independent assortment)

Question 23

Meiosis: Metaphase 1

Answer 23

-Homologous pairs line up on opposite sides of metaphase plate

Question 24

Meiosis: Anaphase 1

Answer 24

-Homologous pairs are pulled to opposite poles of the cell (this accounts for Mendel’s first law of segregation)

Question 25

Meiosis: Telophase 1

Answer 25

-Chromosomes may or may not fully decondense -Cells may enter interkinesis after cytokinesis

Question 26

What is separated in Meiosis 2?

Answer 26

Sister chromatids

Question 27

How is meiosis 2 different from mitosis?

Answer 27

Functionally it is identical, the only difference is sister chromatids are separated instead of chromosomes

Question 28

Where is sperm developed?

Answer 28

In the seminiferous tubules

Question 29

Where are the seminiferous tubules?

Answer 29

In the testes

Question 30

How are sperm nourished?

Answer 30

By Sertoli cells

Question 31

What do the interstitial cells of Leydig do?

Answer 31

They secrete testosterone and other male sex hormones

Question 32

Where are the testes located?

Answer 32

In the scrotum

Question 33

What do seminal vesicles do?

Answer 33

They contribute fructose to nourish sperm and produce alkaline fluid

Question 34

What does the prostate gland do?

Answer 34

It produces alkaline fluid

Question 35

What do the bulbourethral glands do? (AKA Cowper's gland)

Answer 35

Produces a clear, viscous fluid that cleans out remaining urine from the urethra and lubricates the urethra during sexual arousal

Question 36

What is produced by spermatogenesis?

Answer 36

4 haploid sperm cells are produced from a spermatogonium

Question 37

After the S phase, what are the germ cells called?

Answer 37

Primary spermatocytes

Question 38

After meiosis 1, what are the germ cells called?

Answer 38

Secondary spermatocytes

Question 39

After meiosis 2, what are the germ cells called?

Answer 39

Spermatids

Question 40

After maturation, what are the germ cells called?

Answer 40

Spermatozoa

Question 41

What is the head piece of sperm composed of?

Answer 41

-The genetic material -Covered with acrosome

Question 42

What is the acrosome?

Answer 42

A modified golgi apparatus that contains enzymes that helo the sperm fuse with and penetrate the ovum

Question 43

What is the midpiece of sperm composed of?

Answer 43

-Contains many mitochondria -Generates ATP from fructose

Question 44

Where are ova produced?

Answer 44

In follicles

Question 45

Where are follicles?

Answer 45

In the ovaries

Question 46

What is formed during oogenesis?

Answer 46

1 haploid ovum and a variable number of polar bodies (usually 2)

Question 47

Do polar bodies contain genetic info?

Answer 47

No, they are functionally inactive because they receive very little cytosol and organelles

Question 48

What phase are primary oocytes arrested in?

Answer 48

Prophase 1

Question 49

What phase is the secondary oocyte (the ovulated egg) arrested in?

Answer 49

Metaphase 2

Question 50

When will the ovum complete meiosis 2?

Answer 50

When it is fertilized

Question 51

What is the zona pellucida?

Answer 51

-An acellular mixture of glycoproteins that protects the oocyte. -Contains compounds necessary for sperm binding -Also contains the corona radiata

Question 52

What is the corona radiata?

Answer 52

A layer of cells that adheres to the oocyte during ovulation

Question 53

Where is GnRH released from?

Answer 53

The hypothalamus

Question 54

What hormones does GnRH trigger to be released?

Answer 54

FSH and LH

Question 55

In males, what does FSH trigger?

Answer 55

Sertoli cells and spermatogenesis

Question 56

In males, what does LH trigger?

Answer 56

Causes Leydig cells to produce testosterone

Question 57

In females, what does FSH trigger?

Answer 57

Development of ovarian follicles

Question 58

In females, what does LH trigger?

Answer 58

Ovulation

Question 59

What hormones do FSH and LH also trigger?

Answer 59

Testosterone, estrogen, and progesterone

Question 60

What are the phases of the menstrual cycle?

Answer 60

-Follicular -Ovulation -Luteal -Menstruation

Question 61

In the follicular phase, what hormones are released?

Answer 61

-GnRH (which triggers FSH and LH) -FSH triggers follicular development -FSH and LH trigger estrogen -Estrogen establishes uterine lining

Question 62

In the ovulatory phase, what hormones are released?

Answer 62

-LH surge triggers ovulation -LH surge is triggered by estrogen meeting a threshold, which causes a switch from negative to positive feedback

Question 63

In the luteal phase, which hormones are released and inhibited?

Answer 63

-High estrogen and progesterone levels cause negative feedback on GnRH, LH, and FSH -Progesterone maintains uterine lining -Follicle ruptures releasing egg

Question 64

In menstruation, which hormones are released and inhibited?

Answer 64

-Occurs if there is no fertilization -Estrogen and progesterone levels drop -Endometrial lining sloughs off -Block on GnRH is removed

Question 65

If fertilization does occur, what hormone is produced?

Answer 65

hCG is produced by the blastula

Question 66

What does hCG do?

Answer 66

Acts as an LH analog to maintain the corpus luteum

Question 67

When do hCG levels drop off?

Answer 67

Near the end of the first trimester, because the placenta takes over progesterone production

Question 68

In menopause, which hormones are no longer produced?

Answer 68

Estrogen and progesterone

Question 69

In menopause, which hormones are increased?

Answer 69

LH and FSH