Week 1 Learning Objectives

Question 1

What are the major problems that all life must overcome?

Answer 1

Obtaining, digesting, and excretion of food
Homeostasis of water/temperature
Oxygen (Surface to area volume)
Reproduction.

Question 2

What are the steps in embryonic development of Protostomes

Answer 2

1. Spiral mosaic cleavage
2. Mosaic embryo (1-Blastomere excised)
3. Blastopore -> mouth, anus forms secondarily
4. Coelem form by splitting (Schizocoelous).

Question 3

What are the steps in embryonic development of deuterostomes

Answer 3

1. Radial cleavage
2. Regulative embryo (1-Blastomere excised)
3. Blastopore -> anus, mouth forms secondarily
4. Coelom forms by outpocketing entercoelous

Question 4

What defines Diploblastic development

Answer 4

Only 2 germ layers Ecto - Endoderm in embryonic development.
Tend to be Acoelomate. Examples are cnidarians
Ectoderm -> Endoderm -> Gut

Question 5

What defines Triploblastic development

Answer 5

3 germ layers Ecto -> Meso -> Endoderm.

Can be ether Acoelomate (Platyhelminth) or Coelomate (Chordate-echinoderm ect)

Question 6

What is a pseudocoelomate?

Answer 6

An animal with a Coelom not arising from a Mesoderm

Question 7

What is a Coelomate?

Answer 7

An animal that has a Coelom arising from and bound by a Mesoderm layer, the Peritoneum