Chapter 8 & 40

Question 1

Thermodynamics (3)

Answer 1

• Transformations of energy
• Energy flows through ecosystems, usually entering as light and exciting as heat
• Governed by 2 thermodynamic laws: organisms require continuous inputs of energy to stay alive

Question 2

2 Thermodynamic Laws

Answer 2

1. Energy can be transformed but not created/destroyed

2. Every transfer or transformation of energy increases the entropy (disorder) of the universe

Question 3

Energy and Entropy (2)

Answer 3

1. An ecosystem is more ordered (lower entropy (S)) and has more energy (higher H) than a mixture of its constituent atoms
2. Minimum free energy, max entropy is thermodynamically favoured state (equilibrium)

Question 4

Why are organic macromolecules energetically unfavorable? (proteins, nucleic acids, fatty acids etc.)

Answer 4

Synthesis requires an input of energy and breakdown is spontaneous

Question 5

Gibb’s Free Energy (G)

Answer 5

Energy Available to do work. If free energy is negative, process is spontaneous.

-H = energy (enthalpy)
-S = entropy (disorder)
-T = temperature (ink)
^G = ^H - T^S

Question 6

How does energy enter the biosphere?

Answer 6

Through producers. ex: photosynthetic prokaryotes, protists and plants)

Question 7

Consumers

Answer 7

Obtain energy through food and use it to produce ATP (constant energy supply required)

Question 8

What do organisms need to do to maintain life?

Answer 8

Expend energy (metabolism)

Question 9

Basal Metabolic Rate

Answer 9

Minimum metabolism of an unstressed, non-growing endotherm at rest on an empty stomach

Question 10

Standard Metabolic Rate

Answer 10

Ectoderm