2.2 metabolic rate

Question 1

use of an respirometer, oxygen/carbon dioxide probes and calorimeter to measure metabolic rate

Answer 1

respirometer- measuring the metabolic rate by measuring co2 uptake or o2 production.

oxygen/carbon dioxide sensors - by measuring oxygen consumption and carbon dioxide production during respiration.

calorimeter - heat production.

Question 2

organisms with high metabolic rates

Answer 2

animals with high metabolic rates require efficient delivery of oxygen to cells and have very high heartbeats.

Question 3

describe circulatory systems; single ( 1 atrium, 1 ventricle)

Answer 3

blood flows in a single circuit through a two chambered heart. blood at high pressure is reoxygenated at the gills. blood pressure drops in body tissues, leading to relaively low metabolic rate. ( fish )

Question 4

circulatory system; incomplete double 2 atria, 1 ventricle

Answer 4

three chambered heart. deoxgynated blood from body and oxygenated blood from lungs can mix in ventricle, leading to partially oxygenated blood, carrying reduced oxygen concentration. ( reptiles/ amphibians )

Question 5

circulatory system; complete double 2 atria, 2 ventricle

Answer 5

no mixing of oxygenated and deoxygenated blood which are kept separate, this allows blood to be pumped out at higher pressure enabling efficient delivery of oxygen to cells. ( birds / mammals )

Question 6

why complete double enable high metabolic rates to be maintained

Answer 6

higher oxygen concentration in blood allows for maintenance of higher metabolic rates compared to fish/amphibians/ reptiles.

Question 7

external abiotic factors that affect the ability of an organism to maintain it’s metabolic rate

Answer 7

• pH, salinity, temperature

Question 8

influence of external abiotic factors on conformer

Answer 8

an conformer is an organism who’s internal environment depends upon abiotic factors in it’s external environment.

Question 9

how conformers tolerate variation in external environment

Answer 9

behavioural responses allow conformers to tolerate variation in their external environment to maintain their optimum metabolic rate. conformers have low metabolic costs and narrow range of ecological niches.

Question 10

examples of conformer behavioural responses

Answer 10

lizard - basking on rocks - absorb heat from rocks/sun, increase metabolic rate.
monarach butterflies - migrate to warmer climate - hot climate allows butterflies to maintain high body temp.
ladybirds - cluster together - converses heat to allow normal metabolism.

Question 11

regulator

Answer 11

a regulator is an organism who maintains their internal conditions regardless of external environment.

Question 12

how regulators tolerate variation in their external environment

Answer 12

regulators use their metabolism to control their internal environment which increases the range of possible ecological niches.

Question 13

homeostasis

Answer 13

this regulation requires energy to achieve homeostasis.
homeostasis is the regulation of internal conditions in an organism to maintain constant internal conditions, this regulation increases an organism’s metabolic costs.

Question 14

thermoregulation - when an organism maintains constant body temperature regardless of external temperature

Answer 14

process
a factor increase/decrease from it’s norm. Change in temperature is sensed by temperature receptors in the hypothamulas. messages are sent from receptors to effectors which bring about a corrective response to lower/raise factor back to its norm. the corrective response then stops.

Question 15

importance of thermoregulation

Answer 15

thermoregulation is required for optimal enzyme activity and high diffusion rates to maintain metabolism. without this animals would be less able to love around more to find mates or hunt for food.

Question 16

vasoconstriction ( when body temperature decreases )

Answer 16

narrowing of blood vessels in skin, decreases blood flow at surface of skin and decreases heat loss through skin.

Question 17

shivering and metabolic rate

Answer 17

shivering - involuntary muscle contractions generate more heat when body temperature decreases.

increased metabolic rate produces more heat in response to body temperature decrease.

Question 18

hairs on skin (skin responses)

Answer 18

decrease in body temperature causes hair erector muscles to contract, pulling airs upright trapping a layer of insulation air, which warms up body.

Question 19

vasodilation ( when body temperature increases )

Answer 19

widening of blood vessels in skin, increases blood flow at surface of skin which increases heat loss through skin.

Question 20

sweat glands (skin response)

Answer 20

releases more heat in response to body temperature increase, which cools down the body, as heat used to evaporate water in sweat cools down the skin.

Question 21

decreased metabolic rate

Answer 21

decreased metabolic rate produces less heat in response to body temperature increase.

Question 22

dormancy

Answer 22

a period of reduced metabolic activity, in some organism’s lifecycles to allow survival during a period when the costs of continued normal metabolic activity would be too high. Reduction in metabolic rate saves energy.

Question 23

physiological effects on dormancy

Answer 23

decrease in metabolic rate
decrease in heart rate
decrease in breathing rate
decrease in body temperature

Question 24

predictive and consequential dormancy

Answer 24

predictive - organism enters dormancy before adverse conditions occur

consequential - organism becomes dormant after adverse conditions occur

Question 25

hibernation ( predictive / consequential )

Answer 25

sustained lowering of metabolism reduces energy costs to survive low availability of food. It is predictive if it occurs before adverse conditions due to shortening of photoperiod or decrease in temperature.
( bear / dormouse )

Question 26

aestivation ( consequential )

Answer 26

lowered metabolism reduces energy costs to survive in periods of extreme drought or high temperature
( snail, lungfish )

Question 27

daily torpor ( predictive )

Answer 27

daily short term decrease in metabolic rate in organisms with high metabolic rates. Decrease in heart rate, breathing and temperature rate reduces energy costs by up to 90%.
( small birds, humming birds )

Question 28

migration

Answer 28

migration is when an organism avoids metabolic adversity by expanding energy to relocate to more suitable environments.

Question 29

innate (in born ) influences on migration

Answer 29

birds have an instinctive urge to migrate from birth.

Innate triggers for migration can be change in day length or temperature increase/decrease.

Question 30

learned influences on migration

Answer 30

some birds need to follow parents to migrate and to learn migration route. modifications to innate trigger eg specific stop points in order to rest in long migration journeys.

Question 31

radio transmitter

Answer 31

Can be attached to animals in a collar.
Can gather biological information as well.
Requires a tracking radio signal.

Question 32

satellite tracking

Answer 32

Can use different satellite images to track movements of large numbers of animals. e.g. herd movements of gazelle
Can also use satellite positioning from tags which have satellite signal/locators e.g. osprey tracking
Very accurate and a lot of data can be gathered but expensive.

Question 33

ringing

Answer 33

A physical tag ,usually on the legs of birds.
Involves a capture and release and either recapture or observation
Capture can be difficult and distressing (if not handled carefully), identification require careful observers. Long term can build very detailed information.