3.1 metabolism and energy

Question 1

what is energy

Answer 1

ability to do work

Question 2

Living organisms must _________, _________ and _________
energy

Answer 2

capture, store, and use

Question 3

ATP is produced by

Answer 3

mitochondria (in eukaryotes)

Question 4

Metabolism:

Answer 4

sum of the chemical
reactions taking place (catabolic and anabolic reactions)

Question 5

2 types of energy

Answer 5

Kinetic, potential

Question 6

Kinetic Energy

Answer 6

a result of motion

Question 7

Potential Energy:

Answer 7

stored within an object;
depends on location and/or chemical
structure

Question 8

2 types of potential energy

Answer 8

Chemical potential (electrons and protons)
Gravitational potential (distance from Earth)

Question 9

First law of thermodynamics (“Law of Energy Conservation”)

Answer 9

Energy cannot be created nor
destroyed; it can only be changed from
one form to another

Question 10

Example of 1st law of thermodynamics

Answer 10

Light energy comes from the sun

Converted to chemical energy by green plants

Stored in plant cells as carbs

Passed on to other organisms when they eat the plants

Converted to other forms: mechanical, thermal, sound…

Question 11

Energy conversion depends on:

Answer 11

breaking and
re-forming chemical bonds

Question 12

Electrons have more potential energy the
_______ they are from the nucleus

Answer 12

farther

Question 13

True or false: electrons
can be attracted to multiple nuclei at the
same time = chemical bond!

Answer 13

True

Question 14

bonds break: energy is _______

Answer 14

absorbed

Question 15

bonds formed, energy is _________

Answer 15

released

Question 16

A measure of the strength or stability of a
covalent bond is _________

Answer 16

bond energy

Question 17

bond energy

Answer 17

amount of energy released per mole when bonds form

Question 18

Activation energy (Ea)

Answer 18

energy required to begin the reaction

Question 19

True or false: every reaction requires energy to start, even if it produces energy

Answer 19

True

Question 20

Transition state

Answer 20

when bonds are broken and new ones are ready to be formed

Question 21

Exothermic reaction

Answer 21

net release of energy

Question 22

Endothermic reaction

Answer 22

net absorption of energy

Question 23

Second Law of Thermodynamics

Answer 23

Every time energy is converted to
another form, some of the useful energy
becomes unusable and increases the
entropy of the universe

Question 24

Entropy

Answer 24

degree of disorder in a
system

Question 25

True or false: All systems in the universe tend towards entropy

Answer 25

True

Question 26

Entropy is in chemical rxns, usually associated with _________________

Answer 26

particles breaking down (solid -> liquid -> gas)

Question 27

True or false: Entropy also decreases when # product molecules > # reactant molecules

Answer 27

False. Entropy also increases when # product molecules > # reactant molecules

Question 28

Living cells can create order by:

Answer 28

expending energy

Question 29

Spontaneous Changes

Answer 29

One that will continue to occur on its own once it has started

Question 30

Non-spontaneous change

Answer 30

requires continual energy input

Question 31

Need to look at ____________________ to determine spontaneity

Answer 31

energy changes, entropy, and temperature

Question 32

Since rxns aren’t 100% efficient, whatever energy remains to do work is known as _____________

Answer 32

free energy

Question 33

Free energy is represented with

Answer 33

G after Josiah Willard Gibbs

Question 34

exergonic

Answer 34

ΔG is negative (nrg released)

Question 35

endergonic

Answer 35

ΔG is positive (nrg absorbed)

Question 36

spontaneity of exergonic

Answer 36

spontaneous

Question 37

spontaneity of endergonic

Answer 37

non-spontaneous

Question 38

True or false: Cells continuously carry out thousands of rxns (coupled reactions)

Answer 38

True

Question 39

True or false: endergonic rxns release free energy, which can be used to make exergonic rxns happen

Answer 39

False. Exergonic rxns release free energy, which can be used to make endergonic rxns happen

Question 40

spontaneity of coupled reactions

Answer 40

spontaneous because combined, the rxns have negative G

Question 41

Catabolic:

Answer 41

complex molecules broken down, releasing energy (- G)

Question 42

example of catabolic rxn

Answer 42

cellular respiration

Question 43

Anabolic

Answer 43

simple molecules combined, consuming energy (+ G)

Question 44

example of anabolic reaction

Answer 44

photosynthesis

Question 45

True or false: All living things perform activities that increase the free energy available

Answer 45

True

Question 46

Examples of activities that increase free energy available

Answer 46

movement, growth, repair, reproduction

Question 47

A continual supple of energy is required for living things, what does this energy come from?

Answer 47

ATP