Week 1 Objectives 5b: Where the materials come from, and stages in mammalian ovulation

Question 1

Accumulation of cellular materials

1. From external sources

Answer 1

1. “heterosynthesis”
2. follicular or nurse cells
3. yolk sac makes nurse cells

Question 2

Accumulation of cellular materials

2. From oocyte itself

Answer 2

1. “autosynthesis”
2. lampbrush chromosomes
3. Gene amplification, i.e. ribosomal RNA genes

Question 3

Oocyte Accessory Cell Interactions

Corona Radiata

Answer 3

Layer of follicle cells surrounding oocyte

Interacts via gap junctions and microvilli

Question 4

Zona Pellucida

Answer 4

non-cellular membrane

secreted by corona radiata and oocyte

Question 5

Cortical Granules: Size

Answer 5

.5 micrometers to 20 micrometers

Question 6

Cortical Granules found in

Answer 6

Frogs, echinoderms, bivalves and mollusks, hamsters, humans, rabbits

Question 7

Cortical Granules NOT found in

Answer 7

urodeles, birds, insects, and guinea pigs, rat

Question 8

Cortical Granule formation

Answer 8

rER, Golgi apparatus

associated with cytoplasmic side of plasmalemma

Question 9

Stages in mammalian ovulation

Answer 9

1. LH surge
2. LH binds to LH receptors on follicle cells
3. Activates adenyl cyclase
4. Produces progesterone (follicle cells do)
5. Activation of collagenase enzyme
6. Release of corona radiata and oocyte