Module 3: Stages of Animal Development

Question 1

Stages of Animal Development

Answer 1

1. Gametogenesis
2. Fertilization
3. Cleavage
4. Gastrulation
5. Organogenesis
6. Growth
7. Senescence

Question 2

formation of sex cells or gametes from primordial germ cells (PGCs)

Answer 2

gametogenesis

Question 3

precursors of gametes, which, following meiosis, develop as haploid sperm and eggs

Answer 3

primordial germ cells (PGCs)

Question 4

type of cell division that gives rise to haploid gametes

Answer 4

meiosis

Question 5

stage of meiosis that results to two cells with half the chromosome number of the parent cell

Answer 5

first division (Meiosis I)

Question 6

stage of meiosis wherein the daughter cells will have the same chromosome number as the parent cells

Answer 6

second division (Meiosis II)

Question 7

____ haploid cells from meiosis I will become ____ haploid cells after meiosis II

Answer 7

two, four

Question 8

five substages of prophase I

Answer 8

Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis

Question 9

tight pairing of the homologous chromosomes; genes on the chromatids of the homologous chromosomes are aligned with each other

Answer 9

synapsis

Question 10

(substage) synapsis begins; synaptonemal complex forms at specific locations, spreading to cover the entire length of the chromosomes

Answer 10

zygotene

Question 11

lattice of proteins between the homologous chromosomes

Answer 11

synaptonemal complex

Question 12

first source of genetic variation produced by meiosis; exchange of chromosomal segments between non-sister homologous chromatids

Answer 12

crossing over

Question 13

(substage) crossing over occurs, then synaptonemal complex breaks down and the connection between homologous pairs is also removed

Answer 13

pachytene

Question 14

found at the end of prophase I; pairs are held together only at the chiasmata; four sister chromatids of each pair of homologous chromosomes are now visible

Answer 14

tetrads

Question 15

(stage of meiosis) tetrads move to the metaphase plate; homologous pairs orient themselves randomly at the equator

Answer 15

metaphase I

Question 16

(stage of meiosis) second mechanism that introduces variation

Answer 16

metaphase I

Question 17

(stage of meiosis) no more DNA
replication will occur; replicated chromosomes (sister
chromatids) are the ones that line up along the metaphase plate

Answer 17

metaphase II

Question 18

where spermatocytogensis and spermatogenesis occur

Answer 18

wall of the seminiferous tubules

Question 19

initial stage of spermatogenesis; spermatogonia go through mitosis to form more spermatogonia

Answer 19

spermatocytogenesis

Question 20

diploid, stem cells

Answer 20

spermatogonia

Question 21

diploid cells that develop from spermatogonia

Answer 21

primary spermatocytes

Question 22

(spermatogenesis) primary spermatocytes undergo meiosis I to produce _____

Answer 22

two secondary spermatocytes (n)

Question 23

(spermatogenesis) secondary spermatocytes go through meiosis II and produce _____

Answer 23

four spermatids (n)

Question 24

spermatids give rise to mature spermatozoa; go through changes in their form so that they become adapted for fertilization

Answer 24

spermiogenesis

Question 25

membrane-bound compartment at the tip of the head of the spermatid; Golgi apparatus surrounds the anterior of the spermatid

Answer 25

acrosomal cap / acrosome

Question 26

organelle that produces and releases lytic enzymes

Answer 26

Golgi apparatus

Question 27

mitochondria fill the opposite end of the spermatid forming the _____

Answer 27

mid-piece

Question 28

(phase) formation of acrosome

Answer 28

cap phase

Question 29

(phase) elongation of microtubules on one of the centrioles of the spermatid

Answer 29

tail phase

Question 30

(phase) residual cytoplasm and some organelles are removed by phagocytosis

Answer 30

maturation phase

Question 31

(phase) genetic material is tightly packed, highly condensed, and transcriptionally inactive

Answer 31

DNA packaging

Question 32

epithelial cells of the seminiferous tubules that nourish the germ cells attached to them; responsible for the phagocytosis of the residual cytoplasm

Answer 32

Sertoli cells

Question 33

migration of the spermatozoon to the epididymis to become a motile sperm cell

Answer 33

spermiation

Question 34

Sertoli cells secrete testicular fluid to aid sperm as they travel from the seminiferous tubules to the epididymis via _____

Answer 34

peristaltic contraction

Question 35

occurs in the outermost layers of the ovaries

Answer 35

oogenesis

Question 36

germ cell; only divide by mitosis during embryogenesis

Answer 36

oogonium

Question 37

cell that will enter meiosis; develops from oogonium

Answer 37

primary oocyte

Question 38

first meiotic arrest

Answer 38

prophase I (diplotene I)

Question 39

At the time of birth, all future eggs are in the _____ stage

Answer 39

prophase

Question 40

product of meiosis I; primary oocyte divides unequally, with most of the cellular material and organelles going to one cell

Answer 40

secondary oocyte

Question 41

product of meiosis I; other cell which will get one set of chromosomes and a small amount of cytoplasm; degenerates

Answer 41

polar body

Question 42

second meiotic arrest

Answer 42

metaphase II

Question 43

ovum with little yolk

Answer 43

Microlecithal/Alecithal

Question 44

ovum with moderate yolk

Answer 44

Mesolecithal

Question 45

ovum with massive yolk

Answer 45

Macrolecithal

Question 46

ovum where yolk is evenly distributed throughout the cytoplasm as fat droplets and yolk granules

Answer 46

Isolecithal

Question 47

ovum with centrally-placed yolk

Answer 47

Centrolecithal

Question 48

ovum where yolk and cytoplasm tend to accumulate at opposite poles

Answer 48

Telolecithal

Question 49

__ gamete/s is/are produced per primary spermatocyte

Answer 49

4

Question 50

__ gamete/s is/are produced per primary oocyte

Answer 50

1