Intro to Plankton

Question 1

What is diffusion?

Answer 1

The process in which molecules of high concentration will want to move to areas of lower concentration

Question 2

What are hyperosmotic environments?

Answer 2

Cells contain less solute then surrounding water

Question 3

What are hypoosomotic environments?

Answer 3

Cells contain more solute than the surrounding water.

Question 4

What are two reactions to adjust water content?

Answer 4

Adjust water intake and excrete

Body swells or shrinks

Question 5

What are osmoconformers

Answer 5

Salts and small nutrients go across cell membrane without any energy from the cell. .
Often have to stay in a particular salinity that matches their internal concentration

Question 6

What is Osmoregulation

Answer 6

Control through the use of energy, the flow across the membrane via transport mechanisms
Concentration can be adjusted through such techniques as excretion

Question 7

Why does surface area matter?

Answer 7

Organisms need to be able to exchange water, nutrients, waste products, and gases with the marine environment
Often occurs across the surface of marine organisms so amount of surface area is important.
As size increases, S/V ratio decreases

Question 8

How does surface area relate to small or large organisms?

Answer 8

The smaller the organism the more it can rely on simple diffusion (no energy) for the exchange of materials
Larger organisms must use energy to pump materials in and out of themselves.

Question 9

What are marine prokaryotes?

Answer 9

Bacteria and archaea
Both are simple and primitive organisms and similar in size and shape
Prokaryotic (lack membrane-bound organelles)

Question 10

What are marine eukaryotes?

Answer 10

Unicellular micro-algae like 
Diatoms 
Dinoflagellates 
Sillicoflagellates
Coccolithophorids

Question 11

What are the two general types of prokaryotes?

Answer 11

Heterotrophic and autotrophic bacteria

Question 12

What are most heterotrophic bacteria like?

Answer 12

Decomposers that break down waste products and dead organic matter
Ensure recycling of essential nutrients

Question 13

Explain the microbial loop?

Answer 13

1. Breaks down very small organic material
2. Gets digested and becomes part of heterotrophic bacteria that are then eaten by larger organisms
3. Recycles small organic material back into the food web.
4. Dissolved organic material turns into particulate organic material
   Heterotrophic bacteria are primary components of the microbial loop

Question 14

What are autotrophic bacteria mostly like?

Answer 14

Most are photosynthetic

Some are chemosynthetic which get energy by releasing the energy stored in chemical compounds

Question 15

What are cyanobacteria?

Answer 15

Photosynthetic bacteria or blue-green algae

Question 16

What is nitrogen fixation?

Answer 16

Takes N2 and converts it to ammonium

They are primary sources of nitrogen for primary producers and are essential for growth for diatoms

Question 17

What is the appearance of cyanobacteria

Answer 17

Contain chlorophyll pigment which allows cyanobacteria to live deeper in the ocean by absorbing more blue light for photosynthesis.
Blueish pigment = phycocyanin
Reddish pigment = phycoerythrin

Question 18

What do cyanobacteria do?

Answer 18

Can convert atmospheric nitrogen into usable nitrogen compounds which is important for plant growth

Question 19

Describe the endosymbiotic theory?

Answer 19

1. Prokaryotic ancestor was engulfed by another prokaryote which became a mitochondrion
2. A eukaryotic ancestor engulfed a photosynthetic prokaryote which became a chloroplast
   So, all mitochondria seem to have evolved from a single origin

Question 20

What is the evidence for mitochondria endosymbiosis?

Answer 20

Have cell membranes similar to prokaryotes

Have circular DNA similar