Week 3 - The Chemical Level of Organization

Question 1

What are the primary elements composing the human body?

Answer 1

1. Oxygen (O)
2. Carbon (C)
3. Hydrogen (H)
4. Nitrogen (N)

Question 2

What charge is an electron?

Answer 2

Negative

Question 3

What charge is a proton?

Answer 3

Positive

Question 4

What charge is a neutron?

Answer 4

Neutral

Question 5

What charge is an atom?

Answer 5

Neutral

Question 6

What is an anion?

Answer 6

An atom that has gained an electron (negative charge ion)

Question 7

What is a cation?

Answer 7

An atom that has lost an electron

(positive charge ion)

Question 8

What are electrolytes?

Answer 8

Substances that ionize in water. Acids, bases or salts.

Question 9

What is a molecule?

Answer 9

A group of atoms bonded together.

Question 10

What is a molecule composed of different elements called?

Answer 10

A Compound

Question 11

Define: metabolism

Answer 11

The sum of all chemical reactions in the body.

Question 12

Define: energy

Answer 12

The capacity to do work.

Question 13

What is the difference between potential energy and kinetic energy?

Answer 13

Potential energy is the energy contained in matter due to position.

Kinetic energy is the energy of matter in motion.

Question 14

What is activation energy?

Answer 14

The initial energy needed to start a reaction.

Question 15

What is a chemical reaction?

Answer 15

A process that occurs when new bonds are formed or old bonds are broken.

Question 16

What 3 factors influence reaction rates?

Answer 16

1. Concentration
2. Temperature
3. Catalysts (most importantly enzymes)

Question 17

What are the 5 types of chemical reactions?

Answer 17

1. Synthesis
2. Decomposition
3. Exchange
4. Reversible
5. Oxidation-reduction

Question 18

Describe synthesis

Answer 18

A reaction in which two more more atoms, ions, or molecules combine form new & larger molecules.

Question 19

Describe decomposition

Answer 19

A reaction in which large molecules are split into smaller atoms, ions, or molecules.

Question 20

What is the term for the sum of all decomposition reactions in the body?

Answer 20

Catabolism

Question 21

What is the term for the sum of all synthesis reactions in the body?

Answer 21

Anabolism

Question 22

What is an exchange reaction?

Answer 22

A reaction that consists of both synthesis and decomposition reactions.

Question 23

What is a reversible reaction?

Answer 23

A reaction that can go in either direction under different circumstances.

Question 24

What is an oxidation-reduction reaction?

Answer 24

A reaction in which electrons are transferred between atoms and molecules.

Question 25

Are decomposition reactions ***exergonic*** or ***endergonic***?

Answer 25

**Exergonic** (energy-releasing)

Question 26

Are synthesis reactions ***exergonic*** or ***endergonic***?

Answer 26

**Endergonic** (energy-storing)

Question 27

What is the ***most important*** inorganic compound in living systems?

Answer 27

**Water**

Question 28

Describe ***inorganic compounds***

Answer 28

Compounds which are **structurally simple** and **usually lack carbon**

Question 29

Describe ***organic compounds***

Answer 29

Compounds that **_always_** contain **carbon**, and **usually hydrogen**

Question 30

What are the 5 properties of water that support life?

Answer 30

1. Solvency 2. Adhesion 3. Cohesion 4. Chemical reactivity 5. Thermal stability

Question 31

Describe a ***solution***

Answer 31

A substance in which a **solvent dissolves a solute**.

Question 32

A substance with a ***pH below 7*** is considered:

Answer 32

**Acidic**

Question 33

A substance with a ***pH above 7*** is considered:

Answer 33

**Basic**