2.4 - Metabolism in Conformers & Regulators

Question 1

Metabolism in Conformers and Regulators

Answer 1

External abiotic facors affect an organism’s ability to maintain its metablic rate.

Abiotic factors include:
* Temperature
* pH
* Salinity (salt concentration)

Question 2

Conformers

Answer 2

Conformers are organisms who rely on the external environment to maintain their internal environment.

They use behavioural responses to maintain their optimum metabolic rate. E.g lizards bask on hot rocks to maintain optimum metabolic rate.

This allows conformers to tolerate variations in their external environment.

Question 3

Benefit of Conformers

Answer 3

Low metabolic cost because they don’t use costly physiological mechanisms

Question 4

Cost of Conformers

Answer 4

Narrow range of ecological niches - conformers need optimum ecological conditions to survive

Question 5

Regulators

Answer 5

Regulators are organisms who maintain their internal environment regardless of their external environment. E.g camels maintain their body temperature despite fluctuating external temperatures

Question 6

Benefit of Regulators

Answer 6

Regulators use metabolism to control their internal environment which increases the range of possible ecological niches that they can have.

Question 7

Cost of Regulators

Answer 7

Using metabolism requires energy to achieved homeostasis. This increases their metabolic cost.

Question 8

Homeostasis

Answer 8

The metabolic process that allows an organism to reach a stable level

Question 9

Thermoregulation

Answer 9

The metabolic process of maintaining body temperature.

Question 10

Responses to Increase in Body Temperature

Answer 10

• Vasodilation - blood flow to the skin which increases heat loss
• Sweating - increased sweat production, body heat is used to evaporate water in the sweat which cools the skin.
• Decreased metabolic rate - a lower metabolic rate means that less body heat is produced.

Question 11

Responses to Decrease in Body Temperature

Answer 11

• Shivering - muscles contract which generates heat.
• Vasoconstriction - decreased blood flow to the skin which decreses heat loss.
• Hair Erector Muscles Contract - traps a layer of insulating air
• Increased metabolic rate - more heat is produced

Question 12

Process of Thermoregulation

Answer 12

A change in temperature is detected by receptors. This information is communicated by electrical impules through nerves to the hypothalamus.

Information is then sent to the effectors which brings about corrective responses to return the temperature to normal e.g an increase in body temperature would bring about sweating as a corrective response.

Question 13

Hypothalamus

Answer 13

The temperature monitoring centre locked in the brain.

Question 14

Importance of Thermoregulation

Answer 14

Thermoregulation ensures that body temperature is maintained for optimal enzyme activity and high diffusion rates. This allows for metabolism to be maintained.