Biology: Chapter 2: Reproduction

Question 1

Diploid vs Haploid

Answer 1

Diploid (2n) –> two copies of each chromosome
Haploid (n) –> one copy of each chromosome

Question 2

What are the stages of the cell cycle

Answer 2

G1, S, G2 (Interphase) and M

Question 3

what is the G1 phase

Answer 3

cells create organelles for energy and protein production + increase their size (normal cell function)

Question 4

what is the restriction point

Answer 4

between G1 and S where DNA is checked for quality

Question 5

what is S phase

Answer 5

DNA replication

Question 6

what is G2 phase

Answer 6

further cell growth, organelles are copied, cell prepping for mitosis

Question 7

what are the phases of mitosis

Answer 7

prophase, metaphase, anaphase, telophase

Question 8

what is cytokinesis

Answer 8

after telophase; division of the cytoplasm

Question 9

what is p53

Answer 9

protein that plays major roles in checkpoints between G1/S and G2/M

Question 10

How are cyclins and CDK related to the cell cycle

Answer 10

Cyclins bind to CDKs which then phosphorylates/activates transcription factors

Question 11

what is cancer

Answer 11

uninhibited division of damaged cells without regard to quality or quantity

Question 12

Cell cycle of somatic vs gametes

Answer 12

somatic –> mitosis
gametes –> meiosis

Question 13

What is prophase

Answer 13

chromosomes condense, the nuclear envelope dissolves, centrioles migrate to opposite sides and the spindle apparatus forms; kinetochore of each chromosome is contacted by a spindle fiber

Question 14

what is metaphase

Answer 14

chromosomes line up along metaphase plate

Question 15

what is anaphase

Answer 15

sister chromatids are pulled to opposite sites of cell

Question 16

what is telophase

Answer 16

nuclear membrane reforms, spindle apparatus. disappears

Question 17

what are the stages of meiosis

Answer 17

meiosis I –> prophase I, metaphase I, anaphase I, telophase I
Meiosis II –>. prophase II, metaphase II, anaphase II, telophase II

Question 18

what are the two rounds of division in meiosis

Answer 18

reductional division and equational divison

Question 19

what is prophase I

Answer 19

same as prophase except homologues come together and intertwine during synapsis; crossing over exchanges genetic material (Mendels second law)

Question 20

what are homologues

Answer 20

chromosomes given same number but opposite parental origins (NOT IDENTICAL); form a tetrad

Question 21

what is metaphase I

Answer 21

homologous chromosomes line up on opposite sites of metaphase plate

Question 22

what is anaphase I

Answer 22

homologous chromosomes are pulled to opposite poles (Mendels first law of segregation)

Question 23

what is telophase I

Answer 23

chromosomes may or may not decondense; and cell may enter interkinesis after cytokinesis

Question 24

what is meiosis II

Answer 24

functionally similar to stages of mitosis

Question 25

what is hemizygous

Answer 25

males are XY meaning they will express sex linked diseases more frequently

Question 26

what is important about the Y chromosome

Answer 26

carries the SRY (sex determining region Y) which causes the release of androgen so the gonads develop into testes

Question 27

where does sperm develop

Answer 27

in the seminiferous tubules in the testes

Question 28

what are sertoli cells

Answer 28

located in the seminiferous tubules that nourish sperm cells

Question 29

what are the interstitial cells of leydig

Answer 29

located in the testes; secrete testosterone and other sex hormones

Question 30

where are the testes located

Answer 30

scrotum

Question 31

what is the epididymis

Answer 31

located on top of testes; store sperm until ejaculation; where sperm gain motility

Question 32

what is the path of ejaculation (SEVE(N) UP)

Answer 32

S --> Seminiferous tubules E --> Epididymis V --> Vas Deferens E --> Ejaculatory duct U --> Urethra P --> Penis

Question 33

what are the seminal vesicles

Answer 33

contribute fructose to nourish sperm and produce alkaline fluid

Question 34

What is the function of the prostate gland

Answer 34

produces alkaline fluid

Question 35

what is the bulbourethral glands

Answer 35

produce pre-ejaculation that cleans out remnants of urine and lubricates the urethra during sexual arousal

Question 36

what is the stages of development of a mature sperm cell (spermatogenesis)

Answer 36

spermatogonium --> Primary spermatocyte --> secondary spermatocyte --> spermatid --> spermatozoa

Question 37

what is the structure of a sperm cell

Answer 37

head --> acrosome (modified golgi with enzymes to penetrate the ovum) midpiece --> generates ATP from fructose and contains many mitochondira Flagellum

Question 38

where are OVA produced

Answer 38

follicles and ovaries

Question 39

what is oogenesis

Answer 39

one haploid ovum and variable number of polar bodies are formed from oogonium

Question 40

what is a primary oocyte

Answer 40

undergone replication and arrested in prophase I

Question 41

what is a secondary oocyte

Answer 41

ovulated egg which is arrested in metaphase II

Question 42

what happens when oocyte is fertilized

Answer 42

completed meiosis II and becomes and ovum

Question 43

what is the structure of an oocyte

Answer 43

oocytes are surrounded by zona pellucida and the corona radiata

Question 44

what is gonadotropin releasing hormone

Answer 44

released from the hypothalamus and causes the release of follicle stimulating hormone and luteinizing hormone

Question 45

what does FSH and LH do in males

Answer 45

stimulates the sertoli cells and triggers spermatogenesis while LH causes interstitial cells to release testosterone

Question 46

what does FSH and LH do in females

Answer 46

FSH stimulates development of ovarian follicles while LH causes ovulation; also stimulates production of estrogen and progesterone

Question 47

what is the follicular phase of the menstrual cycle

Answer 47

GnRH secretion causes FSH and LH secretion which promotes follicle development; Estrogen is released stimulation vasculatization and glandularization of the decidua

Question 48

what is ovulation

Answer 48

stimulated by surge of LH which is triggered by estrogen levels reaching a threshold in the follicular phase causing a positive feedback loop

Question 49

what is the luteal phase

Answer 49

LH causes the ruptured follicle to become the corpus luteum which secrete progesterone that maintains the uterine lining; High estrogen and progesterone levels cause negative feedback on GnRH, LH, and FSH

Question 50

what is menstration

Answer 50

occurs with no fertilization; estrogen and progesterone levels drop and block on GnRH production is removed

Question 51

what happens during menstrual cycle if fertilization happens

Answer 51

the blastula produces human chorionic gonadtropin (hCG) which maintains corpus luteum; near end of first trimester hCG levels drop as the placenta takes over progesterone production

Question 52

what happens during menopause

Answer 52

ovaries stop producing estrogen and progesterone; menstruation stops and FSH and LH levels rise