Biology Chapter 2: Reproduction (3 Stars)

Question 1

Diploid (2n) cells have ____ copies of each chromosome; ______ cells have one copy.

Answer 1

Two
haploid (n)

Question 2

The cell cycle contains five stages. The G1, S, and G2 stages are collectively called _____, during which the DNA is uncoiled in the form of chromatin.

Answer 2

Interphase

Question 3

In the _____ stage, cells create organelles for energy and protein production, while also increasing their size.

Answer 3

G1 stage (presynthetic gap),
The restriction point, during which the DNA is checked for quality, must be passed for the cell to move into the S stage.

Question 4

In the S stage (synthesis), DNA is _______.

Answer 4

DNA is replicated. The strands of DNA, called chromatids, are held together at the centromere.

Question 5

In the G2 stage (postsynthetic gap), there is further ____ and replication of ______ in preparation for mitosis. Another quality checkpoint must be passed for the cell to enter into mitosis.

Answer 5

cell growth and replication of organelles
Checkpoint must be passed for the cell to enter into mitosis.

Question 6

In the ____ stage , mitosis and cytokinesis occur.

Answer 6

M stage (mitosis)

Question 7

In the ____ stage, the cell performs its function without any preparation for division.

Answer 7

G0 stage

Question 8

p53 plays a role in the ____ major checkpoints of the cell cycle A & B

Answer 8

2v major checkpoints of the cell cycle
(G1 to S, and G2 to M).

Question 9

Cyclins bind to _____, phosphorylating and activating transcription factors for the next stage of the cell cycle.

Answer 9

CDKs

Question 10

Cancer occurs when cell cycle control becomes deranged, allowing damaged cells to undergo _____ without regard to quality or quantity of the new cells produced. Cancerous cells may begin to produce ______ that allow them to escape their site and invade or metastasize elsewhere.

Answer 10

mitosis
factors

Question 11

Mitosis produces two genetically identical haploid or diploid ______ cells from a single cell and occurs in somatic cells.

Answer 11

identical diploid daughter

Question 12

In _______, (CNNCS)
chromosomes condense
nuclear membrane dissolves
nucleoli disappear,
centrioles migrate to opposite sides of the cell,
spindle apparatus begins to form.

Answer 12

prophase
The kinetochore of each chromosome is contacted by a spindle fiber.

Question 13

What happens in metaphase?

Answer 13

In metaphase, chromosomes line up along the metaphase plate (equatorial plate).

Question 14

In _______, sister chromatids are separated and pulled to opposite poles.

Answer 14

Anaphase

Question 15

What happens in telophase? NSC

Answer 15

In telophase,
the nuclear membrane reforms,
spindle apparatus disappears,
cytosol and organelles are split between the two daughter cells through cytokinesis.

Question 16

Meiosis occurs in _______ and produces up to_____ nonidentical haploid sex cells (gametes).

Answer 16

gametocytes (germ cells)
4

Question 17

Meiosis has ____# round of replication and____ # rounds of division

Answer 17

1 round of replication
2 rounds of division (the reductional and equational divisions)

Question 18

In meiosis I, ______ pairs of chromosomes are separated from each other.

Answer 18

Homologous: are chromosomes that are given the same number, but are of opposite parental origin.

Question 19

In prophase I, the same events occur as in prophase of mitosis, except _______.
The # chromatids are referred to as a tetrad
This accounts for Mendel’s _____ law (of independent assortment).

Answer 19

that homologues come together and intertwine in a process called synapsis.
4 chromatids are referred to as a tetrad
Mendel’s second law (of independent assortment).

Question 20

In metaphase I, _______ chromosomes line up on opposite sides of the metaphase plate.

Answer 20

homologous

Question 21

In ______ I, homologous chromosomes are segregated to opposite poles of the cell.
Mendel’s ____ law (of segregation).

Answer 21

anaphase I
Mendel’s first law (of segregation).

Question 22

In ________ I, the chromosomes may or may not fully decondense, and the cell may enter interkinesis after ______.

Answer 22

telophase I
cytokinesis.

Question 23

In meiosis II, _______ are separated from each other in a process that is functionally identical to mitosis. Sister chromatids are copies of the same DNA held together at the centromere.

Answer 23

sister chromatids
Sister chromatids are copies of the same DNA held together at the centromere.

Question 24

Biological sex is determined by the _____ pair of chromosomes in humans, with XX being female and XY being male.

Answer 24

23rd pair

Question 25

The _ chromosome carries a sizeable amount of genetic information

Answer 25

X chromosome

Question 26

The __ chromosome carries little genetic information, but contains the SRY gene

Answer 26

The Y chromosome (sex-determining region Y) gene, which causes the gonads to differentiate into testes.

Question 27

Sperm develop in the ________ in the testes. They are nourished by Sertoli cells.

Answer 27

Seminiferous tubules

Question 28

Interstitial cells (of Leydig) secrete _______ and other male sex hormones (androgens).

Answer 28

testosterone

Question 29

The testes are located in the \_\_\_\_\_, which hangs outside of the abdominal cavity and has a temperature 2° to 4°C lower than the rest of the body.

Answer 29

Scrotum

Question 30

Once formed, sperm gain motility in the \_\_\_\_\_\_and are stored there until ejaculation.

Answer 30

Epididymis

Question 31

During ejaculation, sperm travel through the \_\_\_\_\_\_\_\_to the ejaculatory duct to the ______ and out through the penis.

Answer 31

vas deferens urethra

Question 32

The seminal vesicles contribute _____ to nourish sperm and produce alkaline fluid.

Answer 32

fructose

Question 33

The ______ gland also produces alkaline fluid.

Answer 33

Prostate gland

Question 34

The bulbourethral glands produce a clear _____ fluid that cleans out any remnants of urine and lubricates the urethra during sexual arousal.

Answer 34

clear viscous fluid

Question 35

Semen is composed of sperm and _______ from the glands above.

Answer 35

seminal fluid

Question 36

In spermatogenesis, ____ haploid sperm are produced from a spermatogonium.

Answer 36

4

Question 37

After S stage, the germ cells are called ______ spermatocytes.

Answer 37

primary

Question 38

After \_\_\_\_\_\_, the germ cells are called secondary spermatocytes.

Answer 38

meiosis I

Question 39

After meiosis II, the germ cells are called \_\_\_\_\_

Answer 39

spermatids.

Question 40

After \_\_\_\_\_\_\_, the germ cells are called spermatozoa.

Answer 40

maturation

Question 41

Sperm contain a head, \_\_\_\_\_\_, and flagellum.

Answer 41

midpiece

Question 42

The\_\_\_\_\_ contains the genetic material and is covered with an acrosome— a modified Golgi apparatus that contains enzymes that help the sperm fuse to and penetrate the ovum.

Answer 42

head

Question 43

The midpiece generates _____ from fructose and contains many mitochondria.

Answer 43

ATP

Question 44

The flagellum promotes \_\_\_\_\_\_.

Answer 44

motility

Question 45

The female reproductive system only contains \_\_\_\_\_\_structures.

Answer 45

internal

Question 46

Ova (eggs) are produced in ______ in the ovaries.

Answer 46

follicles

Question 47

Once each month, an egg is ovulated into the _______ and is drawn into the fallopian tube or oviduct.

Answer 47

peritoneal sac

Question 48

The fallopian tubes are connected to the \_\_\_\_\_, the lower end of which is called the cervix.

Answer 48

uterus.

Question 49

The vaginal canal lies below the ______ and is the site where sperm are deposited during intercourse. Birth also occurs here.

Answer 49

cervix

Question 50

The external female anatomy is known as the \_\_\_\_\_.

Answer 50

vulva

Question 51

In oogenesis, one _____ ovum and a variable number of polar bodies are formed from an oogonium.

Answer 51

haploid

Question 52

At birth, all oogonia have already undergone replication and are considered _____ oocytes. They are arrested in ______ I.

Answer 52

primary oocytes prophase I.

Question 53

The ovulated egg each month is a secondary oocyte, which is arrested in ________ II.

Answer 53

metaphase II.

Question 54

If the oocyte is fertilized, it will complete meiosis II to become a \_\_\_\_\_\_\_.

Answer 54

true ovum.

Question 55

Cytokinesis is uneven in oogenesis. The cell receiving very little cytoplasm and organelles is called a \_\_\_\_\_

Answer 55

polar body.

Question 56

Oocytes are surrounded by the \_\_\_\_\_\_\_, an acellular mixture of glycoproteins that protect the oocyte and contain the compounds necessary for sperm binding, and the corona radiata, which is a layer of cells that adhered to the oocyte during ovulation.

Answer 56

zona pellucida

Question 57

Gonadotropin-releasing hormone (GnRH) from the hypothalamus causes the release of follicle-stimulating hormone (FSH) and \_\_\_\_\_\_\_\_\_\_, the functions of which depend on the sex of the individual.

Answer 57

luteinizing hormone (LH)

Question 58

In males, _____ stimulates the Sertoli cells and triggers spermatogenesis, while ____ causes the interstitial cells to produce testosterone.

Answer 58

FSH LH

Question 59

In females, _____ stimulates development of the ovarian follicles, while LH causes ovulation. These hormones also stimulate production of ____ and \_\_\_\_\_

Answer 59

FSH estrogens and progesterone.

Question 60

The menstrual cycle is a periodic growth and _____ of the endometrial lining.

Answer 60

shedding

Question 61

GnRH secretion stimulates FSH and LH secretion, which promotes ______ development.

Answer 61

follicle development. Estrogen is released, stimulating vascularization and glandularization of the decidua.

Question 62

Ovulation is stimulated by a sudden surge in \_\_\_\_\_. This surge occurs because estrogen stops having negative feedback effects at a certain threshold and begins to have positive feedback effects.

Answer 62

LH.

Question 63

In the luteal phase, ____ promotes the ruptured follicle to become the corpus luteum, which secretes progesterone that maintains the uterine lining. High estrogen and progesterone levels cause ______ feedback on GnRH, LH, and FSH.

Answer 63

LH negative feedback

Question 64

Menstruation occurs if there is no fertilization. As the estrogen and progesterone levels drop, the endometrial lining is sloughed off, and the block on _____ production is removed.

Answer 64

GnRH

Question 65

If fertilization does occur, the _____ produces\_\_\_\_\_\_which, as an LH analog, can maintain the corpus luteum.

Answer 65

blastula human chorionic gonadotropin (hCG) Near the end of the first trimester, hCG levels drop as the placenta takes over progesterone production.

Question 66

Menopause occurs when the ovaries stop producing ____ and \_\_\_\_\_\_, usually between ages 45 and 55. Menstruation stops and ____ and _____ levels rise. Physical and physiological changes accompanying menopause include flushing, hot flashes, bloating, headaches, and irritability.

Answer 66

estrogen and progesterone, FSH and LH levels rise.

Question 67

Mutations of \_\_\_\_-linked genes can cause sex-linked disorders.

Answer 67

X-linked

Question 68

\_\_\_\_\_ are hemizygous with respect to the unpaired genes on the X chromosome, so they will express sex-linked disorders, even if they only have one recessive disease-carrying allele.

Answer 68

Males

Question 69

\_\_\_\_\_ with one copy of the affected allele are called carriers.

Answer 69

Women

Question 70

What is Testosterone responsible for?

Answer 70

Maintenance and development of the male reproductive system male secondary sex characteristics (facial and axillary hair, deepening of the voice, and changes in growth patterns).

Question 71

Difference between Mitosis & Meosis:

Answer 71

Question 72

How is Metaphase I different from Metaphase (Mitosis)?

Answer 72

Homologous chromosomes line up on opposite sides of the metaphase plate, rather than individual chromosomes lining up on the metaphase plate