Lab 2: Porifera (sponges)

Question 1

Based on what you have learned from the reading so far, which clade(s) do sponges belong to: Archaea, Eukarya, Metazoa, Eumetazoa?

Answer 1

Eukarya, Metazoa

Question 2

Which layers of the sponge are composed of living cells?

Answer 2

Outer and Inner

Question 3

Are choanocytes located in the outer layer, middle layer, or inner layer of the sponge body wall?

Answer 3

Inner

Question 4

How many layers of choanocytes are in the inner layer of the sponge body wall?

Answer 4

One

Question 5

Does water enter or leave the sponge through the pores?

Answer 5

Enters

Question 6

Does water enter or leave through the osculum?

Answer 6

Leaves

Question 7

What is the function of spicules and spongin?

Answer 7

Shape and support

Question 8

What cell creates the current of water through the sponge?

Answer 8

Choanocyte

Question 9

Where are the choanocyte cells located in the body wall of a sponge?

Answer 9

Inner layer of body wall

Question 10

What role does the microvilli of the cell you named play in getting nutrients?

Answer 10

Traps food flowing in the water current

Question 11

What role does the amoebocyte play in the task of getting nutrients?

Answer 11

Distributes nutrients to all parts of the sponge

Question 12

Sponges do gas exchange by direct diffusion. Which of the following correctly describes what this means?

Answer 12

Each cell of the sponge does gas exchange for itself.

Question 13

Never use the ______ adjustment knob to focus to focus when using the 40X objective. Instead, adjust the focus with ____ focus adjustment knob

Answer 13

Course; fine focus

Question 14

Porifera is organized at the ____ level

Answer 14

Cellular

Question 15

Sponges have all of the following characteristics EXCEPT:
a)Eukaryotic
b)Multicellular
c)Asymmetry
d)Cells organized into tissues

Answer 15

D.

Question 16

What is required to convert the energy in the chemical bonds of food into the chemical energy of ATP?

Answer 16

Oxygen

Question 17

What is the feeding strategy used by sponges?

Answer 17

Suspension feeding

Question 18

Do sponges have neurons?

Answer 18

No

Question 19

What are the three domains of life?

Answer 19

Eukarya, Bacteria, and Archaea

Question 20

What are homologous characters?

Answer 20

similar characters shared by two groups of animals because their common ancestor had the trait

Question 21

What are analogous characters?

Answer 21

Animals who have a similar character that is not due to common ancestry but due to similar selective pressures

Question 22

What is convergent evolution?

Answer 22

The evolution of analogous traits

Question 23

What is the clade eumetazoa and why are sponges excluded from it?

Answer 23

All animals are placed within this clade because their cells form true tissues while sponges do not

Question 24

What does a body plan include?

Answer 24

Body symmetry, presence or absence of true tissues, type of support, organization of nervous system, pattern of development, absence or presence of body cavity

Question 25

What are the tasks of staying alive?

Answer 25

1) Obtaining nutrients from food
2) Breathing to get oxygen and get rid of CO2
3) Getting rid of other things it cannot store (waste)

Question 26

What is mesohyl?

Answer 26

A gel-like substance in the middle layer of the sponge composed primarily of the protein, collagen and secreted by the sponge cells

Question 27

What are the cells that make up the one outer layer of the sponge?

Answer 27

Pinactocytes

Question 28

What is diffusion?

Answer 28

The net, passive movement of molecules from a region of higher concentration to lower concentration; this is a slow process; cells must be near source of oxygen, only effective over short distances

Question 29

Oxygen diffuses from the ____ of the cell across the surface to the ___

Answer 29

Outside; inside