final exam prep

Question 0

Some benefits of oxygen use in the evolution of organisms

Answer 0

Increases in animal size, complexity, size, and movement

Question 1

what is the primry role of O2 in physiolgy

Answer 1

electron acceptor in aerobic respiration; increased efficiency of energy production

Question 2

What are the requirements for obtaining oxygen?

Answer 2

Interface with the environment and respiratory pigments; also require a trnsport mechanism (such as a circulatory system)

Question 3

Characteristics of respiratory pigments

Answer 3

metal-protein complexes, colored

Question 4

4 Functions of respiratory pigments

Answer 4

O2 transport and storage
Facilitate diffusion
O2 sensor
O2 protection ???

Question 5

4 major groups of respiratory pigments differ based on

Answer 5

binding characteristics
color
metal used

Question 6

4 major types of respiratory pigment

Answer 6

Hemoglobin
Chlorocruorin
Hemerythrin
Hemocyanin (Cu)

Question 7

How does O2 binding affect Hemoglobin molecules

Answer 7

Hemoglobin made of four heme groups
O2 binding causes conformational changes such that O2 affinity is increased with each molecule bound
Allows for rapid uptake and release of O2

Question 8

4 factors that affect O2 dissociation

Answer 8

Temperature
pH
CO2
Inorganic ions

Question 9

P50

Answer 9

the PO2 at which respiratory pigments are 50% saturated

Increased P50 means decreased affinity for O2

Question 10

How does salt affect o2 dissociation?

Answer 10

increased salt means decreased affinity (increased P50)

Question 11

How do CO2 and pH affect O2 binding and carrying capacity

Answer 11

Co2 (which decreases pH) and a decrease in pH in general cause a decreased affinity for O2 to respiratory pigments.

Question 12

Root effect

Answer 12

Decrease in overall carrying capacity of O2 in a respiratory pigment due to a decrease in pH

Question 13

Bohr effect

Answer 13

A decrease in the binding affinity (or increase in P50) due to decreased pH.

Question 14

Why is the Bohr effect a GOOD thing?

Answer 14

because, as you get to tissuesthat are O2 poor, that have ncreased Co2, it facilitates release of O2 into those tissues.

Question 15

three aspects of gill form that are highly conserved among taxa

Answer 15

Structure (high surface area)
position (area of increased water flow/exposure)
Function (O2 uptake, transport)

Question 16

3 mechanisms to remove CO2 from tissues

Answer 16

1. Diffusion into blood
2. binding to hemoglobin
3. Bicarbonate buffer system

Question 17

3 main functions of blood

Answer 17

1. Transport of solutes and cells
2. transport of heat
3. Transmission of force

Question 18

3 parts of a circulatory system

Answer 18

1. Pump (heart)
2. Conduit (blood vessels)
3. exchange stations (sinuses. capillary beds, lung, kidneys.)

Question 19

which respiratory pigment lacks cooperative binding kinetcs?

Answer 19

Hemocyanin; only has one subunit. 1/4 as efficient as hemoglobin.

Question 20

two important properties of temperature

Answer 20

1. primary determinant of metabolic rate (and therefore food and energy conumption.)
2. Primary determinant of protein/tissue function

Question 21

what are 3 ways that temperature has an impact on protein/tissue function?

Answer 21

1. Protein conformation and enzymatic rates
2. Rates of diffusion and osmosis
3. Physical state of cells (membrane viscosity)

Question 22

Types of thermal relations (4)

Answer 22

1. Endotherms
2. Ectotherms or poikilotherms (poikilo means variable)
3. thermoregulating (behavioral or homeothermic via physiology)
4. Nonthermalregulating

Question 23

Why are there very few homeothermic aquatic organisms?

Answer 23

Heat convection in the water makes it difficult and neergetically costly

Question 24

Convection

Answer 24

heat transfer via the flow of a material substance, much faster than conduction

Question 25

Most common type of thermal relation (aquatic or otherwise)

Answer 25

ectothermic

Question 26

Eury vs steno thermal

Answer 26

May function over a broad or narrow temperature range.

Question 27

Critical thermal maximum (Ct max)

Answer 27

thermal limit
may be defined by mortality or loss of coordination
Ultimate Ct max-boiling point of water
Duration of thermal exposure important

Question 28

3 ways organisms might respond to high temps

Answer 28

1. Regulate via evaporative cooling (not available to aquatic orgs!)
2. Behavioral responses
3. Biochemical or physical adaptations

Question 29

Two easy behavioral repsonses

Answer 29

1. Leave area (for highly mobile species)

2. Sessile/less mobile may alter burrow depth to buffer against thermal changes

Question 30

two examples of physical adaptiations to temperature

Answer 30

1. Alterations in pigment

2. Blubber or other insulation

Question 31

Q10

Answer 31

the rate by which a reaction increases with a 10 degree increase in temperature
Q10 is usually beteen 2 and 3 for poikilothermic species

Question 32

pejus temperature

Answer 32

the temperature of turning worse

Question 33

Membrane fluidity depends in large part to the degree of

Answer 33

hydrocarbon saturation

Question 34

Saturated hydrocarbons means

Answer 34

no double bonds!

Question 35

the degree of chemical unsaturation of the hydrocarbon tails of brain phospholipids varies with

Answer 35

habitat temperatre

Question 36

Organisms that are warm adapted will have membrane phospholipids that are primarily

Answer 36

saturated

Question 37

organsims that are primarily cold adapted will have membranes that are more

Answer 37

unsaturated.

Question 38

How does degree of saturation of phospholipids alter membrane viscosity

Answer 38

Saturated phospholipds tend to have straight fatty acid tails, which encourages tigheter packing of molecules, creating a more “solid” lipid structure.
Unsaturated phospholipds had kinked fatty acid tails due to the introduction of double bonds between carbons of the fatty acid chains. This contributes to increased viscosity of the lipid, as molecules cannot pack as tightly.

Question 39

4 problems associated with the cold

Answer 39

1. Decreased membrane fluidity
2. Freezing
3. intracellular ice crystal formation is lethal to cells
4. Extracellular ice formation my be tolerated but dehydrates cells due to changes in osmotic gradients

Question 40

How do antifreeze proteins work

Answer 40

They bind to ice crystals to prevent further growth