Chapter 2: Introduction to the chemistry of life

Question 1

The smallest unit of an element that exists as a stable entity.

Answer 1

Atom

Question 2

A substance containing only one type of atom

Answer 2

Element

Question 3

A substance containing two or more different types of atoms

Answer 3

Compound

Question 4

How many naturally occurring elements?

Answer 4

92

Question 5

Living tissue composed of

Answer 5

Carbon, hydrogen, oxygen and nitrogen

Question 6

Atom structure

Answer 6

A nucleus containing protons and neutrons

* With electrons orbiting the outside

Question 7

Neutrons are

Answer 7

Neutral and carry no electric charge

Question 8

Protons are

Answer 8

Positively charged

Question 9

Electrons are

Answer 9

Negatively charged

Question 10

What makes one element different from another?

Answer 10

The atomic number

Question 11

The atomic number

Answer 11

Is the number of protons in the nuclei

Question 12

The atomic weight

Answer 12

Of an element is the sum of the protons and neutrons in the nucleus

Question 13

The electron configuration

Answer 13

Describes the distribution of the electrons in each element

Question 14

Electron shells

Answer 14

2 in the first
8 in the second
18 in the third, and
32 in the fourth

Question 15

Isotopes

Answer 15

These are atoms of an element in which there is a different number of neutrons in the nucleus. This does not effect the activity of the atom just the atomic weight.

Question 16

Molecules

Answer 16

Consist of two or more atoms that are chemically combined

Question 17

Compound

Answer 17

two or more elements combined the molecule is referred to as

Question 18

Compounds that contain carbon and hydrogen are classified as

Answer 18

Organic

Question 19

Covalent bonds

Answer 19

Are formed when atoms share their electrons with each other

Question 20

Ionic bonds

Answer 20

Are weaker and are formed by electrons being transferred from one atom to another

Question 21

Cation

Answer 21

Positive charge

Question 22

Anion

Answer 22

Negative charge

Question 23

Electrolyte

Answer 23

an ionic compound dissolved in water and can conduct electricity

Question 24

Mole

Answer 24

Molecular weight in grams of a substance

Question 25

Chloride (normal plasma levels)

Answer 25

97-106 mmol/L or | 97-106 mEq/l

Question 26

Sodium (normal plasma levels)

Answer 26

135-143 mmol/L or | 135-143 mEq/l

Question 27

Glucose (normal plasma levels)

Answer 27

3.5-5.5 mmol/L or | 60-100 mg/100ml

Question 28

Iron (normal plasma levels)

Answer 28

14-35 mmol/L or | 90-196 mg/100ml

Question 29

PH

Answer 29

The concentration of hydrogen ions in a solution is the measure of the acidity of the solution

Question 30

PH scale

Answer 30

0-14 0-6.9 acid 7 neutral 7.9-14 alkaline

Question 31

Ph value of blood

Answer 31

7.35-7.45

Question 32

Ph value of Saliva

Answer 32

5.4-7.5

Question 33

Ph value of Gastric Juice

Answer 33

1.5-3.5

Question 34

Ph value of Bile

Answer 34

6-8.5

Question 35

Ph value of Urine

Answer 35

4.5-8

Question 36

PH equation

Answer 36

CO2 + H2O H2CO3 H+ + HCO3- Carbon Water Carbonic Hydrogen Bicarbona dioxide acid ion -te ion

Question 37

Acid base balance

Answer 37

Maintained by the buffer and excretory systems so that the ph range of blood stays within normal, narrow range limits

Question 38

Acidosis

Answer 38

Ph falls below 7.35

Question 39

Alkalosis

Answer 39

Ph rises above 7.45

Question 40

Carbohydrates

Answer 40

Sugars and starches composed of carbon, oxygen and hydrogen. | * Arranged in a ring

Question 41

Glycosidic linkage

Answer 41

two sugars combine to form a bigger sugar and a water molecule is expelled

Question 42

One unit of sugar

Answer 42

Monosaccharide

Question 43

Two sugar units

Answer 43

Disaccharide

Question 44

Many sugar units

Answer 44

Polysaccharide

Question 45

Proteins

Answer 45

Made from amino acids joining together | 20 amino acid types

Question 46

Amino acids always contain

Answer 46

carbon, hydrogen, oxygen and nitrogen and many contain sulphur

Question 47

Peptide bond

Answer 47

two amino acids combine to form a bigger molecule and a water molecule is expelled

Question 48

Protein

Answer 48

is an alternate energy source

Question 49

Glucose is the

Answer 49

prefered source of energy for the cells

Question 50

Lipids are

Answer 50

a diverse group of substances with an inability to mix with water Carbon, hydrogen and oxygen

Question 51

Phospholipid

Answer 51

Double layer Cell membrane with a hydrophilic head and hydrophobic tail

Question 52

Fat soluble vitamins

Answer 52

Vitamin A, D, E and K

Question 53

Fats (triglyceride) stored in

Answer 53

Adipose tissue

Question 54

Fats are classified as

Answer 54

Saturated or Unsaturated

Question 55

Saturated

Answer 55

Are solid at room temperature

Question 56

Unsaturated

Answer 56

Are liquid at room temperature

Question 57

Prostaglandins

Answer 57

Important chemicals derived from fatty acids and are involved in inflammation and other processes

Question 58

Cholesterol

Answer 58

is a lipid made in the liver and available in the diet. It is an integral part of cell membranes and is used to make steroid hormones

Question 59

Nucleic acids

Answer 59

Largest molecule in the body and are built from nucleotides. DNA - deoxyribonucleic acid RNA - ribonucleic acid

Question 60

ATP - Adenosine triphosphate

Answer 60

is a nucleotide that contains ribose (the sugar unit), adenine (the base and three phosphate groups 'The energy currency of the body'

Question 61

Enzyme

Answer 61

Proteins that are catalysts for biochemical reactions

Question 62

Substrate

Answer 62

molecule entering an enzyme reaction

Question 63

Active site

Answer 63

the substrate will bind to a specific part of the enzyme

Question 64

Anabolic reaction

Answer 64

When an enzyme catalyses the combination of two or more substances into a larger product

Question 65

Catabolic reaction

Answer 65

Involves the breakdown of the substrate into smaller products, as occurs in digestion of food

Question 66

Diffusion

Answer 66

Movement of molecules down its concentration gradient

Question 67

Passive

Answer 67

requiring no energy

Question 68

Active Transport

Answer 68

requiring energy

Question 69

Osmosis

Answer 69

diffusion of water down its concentration gradient

Question 70

Isotonic

Answer 70

solution equal on both sides of the membrane

Question 71

Hypotonic

Answer 71

a dilute solution

Question 72

Hypertonic

Answer 72

A concentrated solution

Question 73

The total amount of body water in an adult

Answer 73

60% of body weight | 40 litres

Question 74

Extracellular water

Answer 74

22% | 12 litres

Question 75

Intracellular water

Answer 75

38% | 28 litres