Chapter 8 - Metabolism

Question 1

Metabolic pathway

Answer 1

Begins with a specific molecule which is then altered in a series of defined steps, resulting in a certain product

Each step is catalyze by s different enzyme

They regulate metabolic supply and demand

Question 2

Catabolic pathways

Answer 2

Breaks down complex molecules into simpler compounds

Degradative process

Ie cellular respiration (sugar glucose and other organic fuels are broken down in the presence of oxygen to carbon dioxide snd water

Hydrolysis

Energy released from this downhill process can be stored and used to drive uphill (anabolic reactions)

Question 3

Anabolic pathways

Answer 3

Consume energy to build complicated molecules from simpler ones

Sometimes called biosynthetic pathways

Examples are synthesis of an amino acid to make proteins

Dehydration synthesis

Uphill metabolic avenues

Question 4

Bioenergetics

Answer 4

The study of how energy flows through living organisms

Question 5

Energy

Answer 5

The capacity to cause change

Question 6

Kinetic energy

Answer 6

Objects in motion

Release heat

Question 7

Thermal energy

Answer 7

Kinetic energy associated with the random movement of atoms or molecules

Question 8

Potential energy

Answer 8

Energy stored in an object at rest

Question 9

Metabolism

Answer 9

The totality of an organism’s chemical reactions

Emergent property

Arises from orderly interactions between molecules

Question 10

Chemical Energy

Answer 10

The potential energy available for release in a chemical reaction

Question 11

Thermodynamics

Answer 11

The study of energy transformations that occur in a collection of matter

Question 12

Isolated/closed system

Answer 12

Is unable to exchange either energy or matter with its surrounding

Ie liquid in a thermos bottle

Question 13

Open system

Answer 13

Energy and matter can be transferred between the system and its surroundings

Ie organisms

They absorb energy and release heat

Question 14

First law of thermodynamics

Answer 14

The energy of the universe is constant

Energy can be transferred and transformed, but it can’t be created or destroyed.

Also known as the principle of conservation of energy

Plants serve as transformers or producers since they transform the energy of the sun into chemical energy

Question 15

Entropy

Answer 15

The loss of usable energy during energy transfer or transformation that creates to the disorder/ randomness of the universe

Heat is an example of entropy

Heat can only be put to work when there’s a temperature difference (the molecules will move or diffuse from the warm areas to the cool areas)

Living cells are uniform, so they can’t use their heat energy.

Question 16

Second law of thermodynamics

Answer 16

Every energy transfer or transformation increases the entropy of the universe

The universe is becoming more random

Entropy as appears as more heat and less ordered forms of matter

Organisms evolving and becoming more complex don’t violate the second law…even if they decrease entropy, the total entropy of the universe is increasing

Question 17

Spontaneous process

Answer 17

A process that can occur on its own without outside help

Spontaneous means energetically favorable

Entropy helps us understand these reactions because when they occur on their own, they increase the entropy of the universe

Ie water flowing downhill