Lecture 18/19

Question 1

Collagen?

Answer 1

Structural proteins that hold both cells and bodies

Question 2

What are two defining characteristics of animals?

Answer 2

Nervous tissue and muscle tissue

Question 3

Chemoheterotrophic?

Answer 3

Obtain food from chemical, but cannot produce their own carbon based food (consumes other organisms)

Question 4

Sexual reproduction?

Answer 4

Motile haploid sperm fuses with large non-motile haploid egg to make diploid zygote

Question 5

Cleavage?

Answer 5

Mitotic cell divisions in diploid zygote

Question 6

Cleavage leads to?

Answer 6

Formation of hollow blastula (multicellular)

Question 7

Blastula undergoes?

Answer 7

gastrulation

Question 8

Gastrulation?

Answer 8

The forming of a gastrula with different embryonic layers.

Question 9

Protostomes?

Answer 9

Spiral cleavage

Determinate

Question 10

Determinate?

Answer 10

New cell is destined to form parts in later embryo

Question 11

Deuterostomes?

Answer 11

Radial cleavage

Indeterminate

Question 12

Indeterminate?

Answer 12

Early cells not differentiated

Question 13

Protostomia?

Answer 13

First part of gastrula becomes mouth

Question 14

Deuterostomia?

Answer 14

First part of gastrula becomes anus

Question 15

Homeobox?

Answer 15

Highly conserved nucleotide sequence

Question 16

Radial symmetry?

Answer 16

No front and back, left and right

Question 17

Bilateral symmetry?

Answer 17

Two sided symmetry

Question 18

Cephalization?

Answer 18

the development of a head (CNS)

Question 19

Benefits of bilateral symmetry?

Answer 19

• quicker response to stimuli in environment
• better able to search of food
• better defenses capabilities

Question 20

Skin and nervous system is derived from?

Answer 20

Ectoderm

Question 21

Muscles and organs are derived from?

Answer 21

Mesoderm

Question 22

Gut derived from?

Answer 22

Endoderm

Question 23

Most triploblastic organisms have?

Answer 23

Fluid filled body cavity

Question 24

Coelom?

Answer 24

Derived from mesoderm, true body cavity

Question 25

Coelomates?

Answer 25

Animals that have a true coelom

Question 26

Pseudocoelomate?

Answer 26

animals that lack a complete mesodermal lining

Question 27

Acoelomate?

Answer 27

Animals that lack a mesodermal lining entirely

Question 28

Coelom function?

Answer 28

Cushions internal organs from blows to outside the body

Allows internal organs to grow and shift without deforming outside the body

Question 29

Common ancestor of animals resembled?

Answer 29

Choanoflagellates (heterotrophic protist)

Question 30

Colonial hypothesis?

Answer 30

Colony of choanoflagellates may have evolved into an animal with endo and ectodermal layers

Question 31

Evidence of the hypothesis being correct?

Answer 31

Collar cells in sponges identical to choanoflagellate cells

Similar cells found in jellyfish, flatworms, flatworms

Question 32

Advantages of multicellularity

Answer 32

• Foraging: improved handling & feeding of prey (size and coordination)
  
  • Defense: less likely to get eaten
  • Specialization of tasks (sensory, digestion)

Question 33

Disadvantages of multiceullarity?

Answer 33

• Most cells don’t reproduce -support few do

* Requires cooperation - opportunities to cheat (ex: cancer cells)

Question 34

Diffusion?

Answer 34

Random molecule motion from high to low concentration

Question 35

Evolution of Bulk Flow?

Answer 35

Active transport of oxygen, nutrients, and other molecules in large quantities