Lecture 16, 17, & 18

Question 1

What does chemoheterotrophic mean

Answer 1

cannot make own carbon based food source, must consume other organisms

Question 2

What happens during sexual reproduction

Answer 2

motile haploid sperm fertilizes larger non-motile haploid egg to make diploid zygote

Question 3

What are protosomes

Answer 3

a new row of cells slightly twisted off center

spiral cleavage

determinate: new cell forms part of later embryo

Question 4

What are deuterostomes

Answer 4

each cell division stacks the new cells directly above the previous ones

radial cleavage

indeterminate: early embryonic cells not differentiated (could split aka identical twins)

Question 5

What is protostomia

Answer 5

first invagination of the gastrula becomes the mouth

Question 6

What is Deuterostomia

Answer 6

second invagination becomes the mouth

Question 7

What is a homeobox

Answer 7

highly conserved nucleotide sequence

control anterior to posterior developmental sequence of embryo

Question 8

What are Hox genes

Answer 8

homeobox containing genes

Question 9

What is cephalization

Answer 9

the development of a head

Question 10

what is parazoan design

Answer 10

specialized cells for different function

Question 11

what is eumetazoan design

Answer 11

specialized cells aggregated into distinct tissues; more advanced designs (organs)

Question 12

what layers does a diploblastic organism have

Answer 12

endoderm & ectoderm

Question 13

triploblastic

Answer 13

endo-, ecto-, and mesoderm

Question 14

what are coelomates

Answer 14

possess a true coelom

have body cavity called coelom

Question 15

function of a hemocoel

Answer 15

-primary body cavity of most invertebrates

circulation, nutrient transport, waste removal

Question 16

what are triploblastic animals that lack a body cavity called

Answer 16

acoelomates

Question 17

what is the function of a coelom

Answer 17

cushions internal organs from blows to outside body

allows internal organs to grow and shift without deforming outside body

Question 18

what are the advantages of multicellularity

Answer 18

1. Foraging: improved handling & feeding of prey
2. Defense: less likely to get eaten
3. Specialization of tasks

Question 19

What are the costs of multicellularity

Answer 19

1. Most cells dont reproduce
2. requires cooperation

Question 20

Define Diffusion

Answer 20

random motion of molecules from high to low concentration

Question 21

What is bulk flow

Answer 21

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

Question 22

what does sessile mean

Answer 22

sponges attached to one spot, do not move

Question 23

what gives sponges structural support

Answer 23

spicules

Question 24

what is mesophyl

Answer 24

gelatinous acellular layer between the outerskin and choanocyte layer

because it is acellular it is not a tissue

Question 25

what are simultaneous hermaphrodites

Answer 25

male and female at the same time

Question 26

what are sequential hermaphrodites

Answer 26

first one sex, then change to the other

Question 27

where do the egg and sperm arise from in sponges

Answer 27

eggs: amoebocytes sperm: choanocytes

Question 28

what do Cnidaria consist of

Answer 28

-radial symmetry -dipoblastic: have two layers (ecto- and endo derm) -carnivorous -ex. jellyfish

Question 29

What are the two forms of Cnidaria

Answer 29

1. Polyp: oral end upwards, attached to substrate 2. Medusa: oral end downwards, moves freely through water