Chapter 2- Reproduction

Question 1

Germline vs Autosomal Cells
Diploid (2n) vs Haploid (n)
Number of chromosomes

Answer 1

Autosomal (2n) 46 chromosomes

Germline (n) 23 chromosomes

Question 2

Stages of the Cell Cycle

Answer 2

G1 organelles produced, cell growth, restriction point 1
S dna replication (chromatids replicate 46 chromosomes)
G2 growth, restriction point 2
M Mitosis and Cytokinesis

Question 3

What are the total number of chromosomes after the S phase of the cell cycle?

Answer 3

46

Question 4

What stages of the cell cycle are the two quality checkpoints?

Answer 4

The restriction points are between the do you want an S phase and a G2 and M phase of the cell cycle

Question 5

What proteins assist with the restriction checkpoints of the cell cycle?

Answer 5

p53

Question 6

What molecules are responsible for the cell cycle?

Answer 6

Cyclins and Cyclin dependent kinases

Ultimately lead to phosphorylation on transcription factors

Question 7

How do CDK’s promote transcription

Answer 7

Cyclins bind to cyclin dependent kinases in order to activate the CDK – cyclone complex. The complex can then phosphorylate transcription factors in the transcription factors promote transcription of genes required for the next stage of the cell cycle.

Question 8

What is the gene mutation most commonly found in cancer?

Answer 8

Mutation in the TP53 gene that produces p53

Question 9

What are the four phases of mitosis?

Answer 9

Prophase
Metaphase
Anaphase
Telophase

Question 10

Mitosis only occurs in what cells?

Answer 10

Somatic cells (cells not involved in sexual reproduction)

Question 11

Prophase

Answer 11

🤍Nuclear membrane dissolves
🤍Chromosomes condense
🤍Centriole pairs separate and move to opposite poles of the cell
🤍Spindles/kinetochore form (microtubules)

Question 12

Metaphase

Answer 12

Kinetochore fibers interact with spindle fiber apparatus

Chromosomes align af equitorial plate (metaphase plate)

Question 13

Anaphase

Answer 13

Centromeres split and sister chromatids separate and are pulled toward opposite sides of the cell by the shortening of the kinetichore fibers

Question 14

Telophase and Cytokinesis

Answer 14

Spindle apparatus disappears
Nuclear membrane reforms Chromosomes uncoil

Separation of the cytoplasm so that each daughter cell has enough material to survive on his own

Question 15

Meiosis occurs in ____________ cells.

Answer 15

Gameteocytes (germ cells)

Question 16

Meiosis I

Answer 16

Homologous chromosomes separate resulting in 2 haploid daughter cells

Question 17

Meiosis II

Answer 17

Similar to meiosis separation of chromosomes resulting in haploid daughter cells

Question 18

The human genome consists of how many homologous pairs of chromosomes?

Answer 18

23

Question 19

After S phase, what is the number of chromatids, chromosomes, homologous pairs?

Answer 19

96,46,23

Question 20

What special things occurs at prophase one?

Answer 20

Formation of tetrads in a process called synapsis.

Crossing over the chromatids of homologous chromosomes break at the chiasma and exchange equivalent pieces of DNA.

Question 21

What proteins holds together homologous chromosomes in a tetrad?

Answer 21

Sunaptomemal complex

Question 22

Does crossing over occur between sister chromatids or homologous chromosomes?

Answer 22

Crossing over occurs between homologous chromosomes. Crossing over of sister chromatids would not produce any change.

Question 23

Are genes that are located closer together or farther apart more likely to undergo crossing over?

Answer 23

Genes that are located farther apart are more likely to undergo crossing over and thus less likely to be inherited together.

Question 24

Mendeld second law

Answer 24

Law of independent assortment

Inheritance of one allele has no effect on the likelihood of inheriting certain alleles for other genes.

Question 25

Mendels first law of segregation

Answer 25

Law of Segregation

Distribution of homologous chromosomes to the intermediate daughter cell is random with respect to parental origin

Question 26

What is disjunction and when does it occur in meiosis?

Answer 26

Anaphase 1 of meiosis 1

Each chromosome of parental origin separates from its homologue of maternal origin and the daughter cell can inherit either chromosome randomly.

Question 27

Sex chromosomes are which number in the human genome?

Answer 27

23rd pair of chromosomes

Question 28

What gene is found on the Y chromosome that determines sex?

Answer 28

SRY (Sex determining region Y) codes for a transcription factor that initiates testis differentiation and formation of male gonads.

Question 29

What two components make up the testes?

Answer 29

Seminiferous tubules, interstitial cells of leydig

Question 30

What structure helps elevate and lower the testes to maintain an optimal temperature?

Answer 30

Layer of muscle around the vas deferens

Question 31

What structures combined produces seminal fluid?

Answer 31

Bulbourethal gland, seminal vesicles, prostate gland

Question 32

Seminal vesicles secrete

Answer 32

Seminal fluid, fructose to nourish sperm as well as alkaline fluid

Question 33

Bulbourethral glands secrete

Answer 33

Seminal fluid and clear fluid that cleans out urine during sexual arousal

Question 34

Prostage gland secretes

Answer 34

Seminal fluid, alkaline fluid

Question 35

Which part of the sperm produces ATP from fructose?

Answer 35

Midpiece (filled with mitochondria

Question 36

Eggs are ovulated into what area?

Answer 36

Peritoneal sac

Question 37

Which structure surrounds the oocyte itself and protects it?

Answer 37

Zona pellucide

Surrounded by Corona radiata

Question 38

What causes ovarian atrophy in menopause?

Answer 38

Ovaries become less were sponsored to FSH and LH. Drop in estrogen and progesterone levels causes atrophy of the endometrium.

Question 39

What age is menopause?

Answer 39

45-55