Development

Question 1

Development

Answer 1

modification of structure and physiological characters from fertilization to mature

Question 2

how does cell and tissue become diverse?

Answer 2

due to cell differentiate

Question 3

what is cell differentiate?

Answer 3

change in gene expression

Question 4

3 periods of human embryo

Answer 4

• pre-embryonic period
• embryonic period
• fetal period

Question 5

pre-embryonic period

Answer 5

first two weeks after fertilization of egg

Question 6

embryonic period

Answer 6

– Third through eighth weeks
– All major organ systems begin to
develop

Question 7

fetal period

Answer 7

– Ninth through thirty-eighth weeks
– Growth and development
continues
– Ends at birth

Question 8

fertilization

Answer 8

fusion of two haploid gametes
(each 23 chromosomes)

Question 9

what are the gametes involve in fertilization?

Answer 9

secondary oocyte and sperm

Question 10

zygote

Answer 10

diploid cell with 46 chromosomes

Question 11

which gamete is bigger?

Answer 11

Oocyte is 2000 times larger than sperm

Question 12

Fertilization occurs in uterine
tube within _________ of ovulation

Answer 12

a day

Question 13

what does head of spermatozoon contain?

Answer 13

nucleus and chromosomes

Question 14

acrosome

Answer 14

a compartment at tip of head

Question 15

what structure of sperm contain enzyme essential to fertilize?

Answer 15

acrosome

Question 16

neck of sperm

Answer 16

contain centrioles

Question 17

middle piece of sperm

Answer 17

mitochondria and microtubules

Question 18

tail of sperm

Answer 18

only flagellum in human body

Question 19

which stage does secondary oocyte leave follicle?

Answer 19

metaphase of meiosis II

Question 20

Cells of the ________ __________ surround the oocyte

Answer 20

corona radiata

Question 21

what event must happen to cause fertilization?

Answer 21

sperm must penetrate the corona radiata

Question 22

The sperm binds receptors in
the ______ _________ beneath
corona radiata

Answer 22

zona pellucida

Question 23

role of acrosomal enzymes

Answer 23

create gap in corona radiata (sperm can go thru)

Question 24

Oocyte activation

Answer 24

Fusion between sperm and oocyte membranes

Question 25

Enzymes inactivate sperm receptors and harden the
______ ______________

Answer 25

zona pellucida

Question 26

how many sperm fertilizes?

Answer 26

only one

Question 27

Dad’s contribution

Answer 27

23 chromosomes, 1 centriole, and
determines sex

Question 28

what happen during pre embryonic period

Answer 28

amphimixis, zygote cleavage, and differentiation

Question 29

Amphimixis

Answer 29

the male and female pronuclei (1n+1n) fuse

Question 30

what happen after amphimixis?

Answer 30

zygote begin cleavage ( a series of cell division)

Question 31

As the zygote divides, cells have differing _________ __________

Answer 31

cytoplasmic
compositions

Question 32

gestation

Answer 32

time spent in prenatal development

Question 33

what are the phases of gestation?

Answer 33

• first trimester
• second trimester
• third trimester
  (each trimester is 3 months long)

Question 34

first trimester

Answer 34

• Period of embryological and early fetal development
• Rudiments of all major organ systems appear

Question 35

second trimester

Answer 35

• Development of organs and organ systems
• Body shape and proportions change

Question 36

third trimester

Answer 36

• Rapid fetal growth and deposition of adipose tissue
• Most major organ systems are fully functional

Question 37

4 major stages of first trimester

Answer 37

1. cleavage (zygote -> blastocyst)
2. implantation
3. placentation -> placenta develops
4. embryogenesis

Question 38

which trimester is the most dangerous in prenatal life?

Answer 38

first trimester

Question 39

The cells produced by cleavage divisions are called _________

Answer 39

blastomeres

Question 40

3 days of cleavage, the pre-embryo is a solid ball of cells, which is called:

Answer 40

morula

Question 41

The cells of the morula reorganize into a hollow ball called ______

Answer 41

blastocyst

Question 42

what is the inner cavity of blastocyst called?

Answer 42

blastocoele

Question 43

blastomeres then form ________ and _______

Answer 43

trophoblast and inner cell mass

Question 44

trophoblast

Answer 44

outer layer facilitates nutrient exchange

Question 45

inner cell mass

Answer 45

cells that will form the embryo