Embryogenesis

Question 1

Features of sperm cell

Answer 1

Head- acrosome, genetic material(DNA)- nuclear envelope
Middle- mitochondria(energy to help propel the sperm)
Tail- flagellum (propels sperm towards egg cell)

Question 2

Features of the egg cell

Answer 2

Zona pellucida (glycoproteins- sperm binding)
Mitochondria- energy
Genetic material- DNA- nuclear envelope
Plasma membrane

Question 3

Function of acrosome

Answer 3

Chews up the glycoprotein to prevent polyspermy (other sperm cells from binding to the egg cell)

Question 4

Zygote

Answer 4

Egg cell + sperm

Question 5

Early cleavage

Answer 5

2 cells- 4 cells

Question 6

Cleavage

Answer 6

Division of cells without growth (2 cells- 32 cells)

Question 7

Name the steps in embryogenesis

Answer 7

Zygote(from fertilization)- cleavage- cell differentiation- blastulation- gastrulation- neurulation

Question 8

At what stage in embryogenesis does the zona pellucida disappear

Answer 8

Blastulation

Question 9

what is morula

Answer 9

formed during cleavage at 32 cells

“mulberry”

Question 10

what are the differentiated cells at the beginning of blastulation

Answer 10

trophoblasts & embryoblasts

Question 11

what do embryoblasts end up as

Answer 11

embryo

Question 12

end function of trophoblast

Answer 12

aids in embryo implantation to the uterus (placenta)

Question 13

what 2 cells start the gastrulation process

Answer 13

epiblasts and hypoblasts

Question 14

Name the 3 germ layers and the cells they are formed from

Answer 14

Ectoderm- epiblasts
mesoderm- primitive streak
endoderm- hypoblasts

Question 15

what structure depicts the beginning of neurulation

Answer 15

Notochord

Question 16

which category of mesoderm forms the notochord

Answer 16

axial mesoderm

Question 17

location and function of the cortical granules

Answer 17

underneath the plasma membrane; chews up the zona pellucida

Question 18

what forms the neural tube

Answer 18

the neural plate formed by the notochord leaks into the mesoderm to form the neural tube

Question 19

location & function of neural crest cells

Answer 19

Ectoderm; brain & spinal cord

Question 20

Function of neural tube

Answer 20

PNS & SNS; other bones and connective tissue of face

Question 21

Name the categories of the mesoderm

Answer 21

1. Axial mesoderm- notochord
2. paraxial mesoderm- somites- differentiates into muscles, cartilage, bone & dermis
3. lateral mesoderm- heart, blood vessels, body wall, organ muscle
4. intermediate mesoderm- kidney, adrenal glands, genitourinary

Question 22

differentiated cells/organs of ectoderm

Answer 22

skin(epidermis); skin appendages- hair, nails; nervous system, brain

Question 23

Differentiated cells/organs of mesoderm

Answer 23

muscles, genitourinary, skeletal, notochord, circulatory system, connective tissue, bone

Question 24

Differentiated cells/organs of endoderm

Answer 24

the epithelial lining of the digestive tract- stomach, liver, colon, pancreas; pulmonary- lungs, distal ends of thr urinary tract