LEC3. Chemical Composition of a Living Matters

Question 1

__________ is anything that takes up space and has mass.

Answer 1

Matter

Question 2

Matter is made up of __________, substance that cannot be broken down to other substances by chemical reactions.

Answer 2

Elements

Question 3

__________ is a substance consisting of two or more different elements combined in a fixed ratio.

Answer 3

Compound

Question 4

4 Elements making up about 96% of human body weight:

Answer 4

1. Oxygen (65.0)
2. Carbon (18.5)
3. Hydrogen (9.5)
4. Nitrogen (3.3)

Question 5

7 Elements making up about 4% of human body weight:

Answer 5

1. Calcium (1.5)
2. Phosphorous (1.0)
3. Potassium (0.4)
4. Sulfur (0.3)
5. Sodium (0.2)
6. Chlorine (0.2)
7. Magnesium (0.1)

Question 6

__________ are those required by an organism in only minute quantities

Answer 6

Trace elements

Question 7

Trace elements that make up <0.01%:

Answer 7

boron, chromium, cobalt, copper, fluorine, iodine, iron, manganese, molybdenum, selenium, silicon, tin, vanadium, zinc

Question 8

Greek philosopher who lived in the 5th century BC. He is considered to be one of the founders of the atomic theory of matter.

Answer 8

Democritus

Question 9

All matter was made up of tiny, indivisible particles called __________. These are the smallest units of matter that can exist alone.

Answer 9

Atoms

Question 10

The word atom is from the Greek word meaning __________.

Answer 10

Uncuttable

Question 11

Atoms are constructed of three major subatomic particles:

Answer 11

1. Neutrons
2. Protons
3. Electrons

Question 12

__________ are heavy subatomic particles that do not have a charge; it is located in the central core of each atom.

Answer 12

Neutrons

Question 13

__________ are heavy subatomic particle that has a positive charge; it is located in the atomic nucleus.

Answer 13

Protons

Question 14

__________ are light subatomic particle with a negative electrical charge that moves about outside the atomic nucleus in regions known as energy levels.

Answer 14

Electrons

Question 15

The ___________ of an element is the number of protons in an atom of that element.

Answer 15

atomic number

Question 16

__________ is the sum of the number of protons and neutrons in the nucleus of an atom

Answer 16

Mass number

Question 17

All atoms of a given element have the same number of protons, but some atoms have
more neutrons than another atoms of the same element and therefore have greater
mass. These different atomic forms are called __________ of the element.

Answer 17

isotopes

Question 18

__________ is an essential molecule for life on Earth. It is the most abundant molecule on Earth.

Answer 18

Water

Question 19

Most cells are about how much water?

Answer 19

70-95%

Question 20

The water molecule is shaped something like a wide V, with its two hydrogen atoms joined to the oxygen atom by __________.

Answer 20

single covalent bonds

Question 21

The water molecule is a __________ because the two ends have opposite charges: the oxygen region has a partial negative charge (δ-) & the hydrogens have a partial positive charge (δ+)

Answer 21

polar molecule

Question 22

Two water molecules are held together by a __________

Answer 22

hydrogen bond

Question 23

4 Properties of Water:

Answer 23

1. Cohesive Behavior
2. Ability to Moderate Temperature
3. Expansion upon Freezing
4. Versatility as Solvent

Question 24

__________ is a measure of how difficult it is to stretch or break the surface of a liquid

Answer 24

Surface Tension

Question 25

__________ is the force that holds water molecules together. It is caused by the hydrogen bonds between the water molecules. Hydrogen bonds are weak bonds, but they are very important for the structure and properties of water.

Answer 25

Cohesion

Question 26

__________ is the force that holds water molecules to other surfaces. It is also caused by the hydrogen bonds between the water molecules and the surface.

Answer 26

Adhesion

Question 27

Water’s specific heat is __________

Answer 27

1cal/gm/0C

Question 28

__________ is the process of cooling a surface by the evaporation of a liquid. It is a common method of cooling in hot climates, and it is also used in some industrial processes.

Answer 28

Evaporative cooling

Question 29

__________ (vaporization) is the transformation from a liquid to gas

Answer 29

Evaporation

Question 30

While other materials contract when they solidify, water expands

Answer 30

Expansion upon Freezing

Question 31

Cohesion due to hydrogen bonding contributes to the transport of water & dissolved nutrients against gravity in plants

Answer 31

Cohesive Behavior

Question 32

__________ is a liquid that is completely homogenous mixture of 2 or more substances

Answer 32

Solution

Question 33

__________ is the dissolving agent of a solution

Answer 33

Solvent

Question 34

__________ is the substance that is dissolved

Answer 34

Solute

Question 35

__________ is one in which water is the solvent

Answer 35

Aqueous solution

Question 36

Any substances that has an affinity for water

Answer 36

Hydrophilic substances

Question 37

Any substances that do not have affinity for water because they are non-ionic & nonpolar that seem to repel water

Answer 37

Hydrophobic substances

Question 38

A stable suspension of fine particles in a liquid

Answer 38

Colloid

Question 39

It is a substance that increases the hydrogen ion (H+) concentrates of a solution & removes hydroxide ions (OH-) in a solution

Answer 39

Acids

Question 40

TRUE OR FALSE Water is a universal solvent

Answer 40

True

Question 41

TRUE OR FALSE The lower the pH level, the stronger the acid is

Answer 41

True

Question 42

TRUE OR FALSE Cola and HCl have the same pH

Answer 42

True

Question 43

It is a substance that reduces the H+ concentration of a solution & increases OH- in a solution

Answer 43

Base

Question 44

TRUE OR FALSE Hydrochloric acid (HCl) is an example of a strong acid

Answer 44

True

Question 45

TRUE OR FALSE Sodium hydroxide (NaOH) is an example of a strong base

Answer 45

True

Question 46

TRUE OR FALSE The higher the pH level, the stronger the base is

Answer 46

True

Question 47

The pH of human blood is very close to 7.4, which is slightly basic. A person cannot survive for more than a few minutes if the blood pH drops to 7 or rises to 7.8

Answer 47

Neutral pH

Question 48

A chemical system exists in the blood that maintains a stable pH called the __________ Are substances that minimize the changes in the concentration of H+ & OH- in a solution

Answer 48

buffering system

Question 49

TRUE OR FALSE Hydrochloric acid (HCl) is an example of a strong acid

Answer 49

True

Question 49

Compounds formed by ionic bonds They are often found in nature as crystals of various sizes & shapes

Answer 49

Salts

Question 49

__________ are organic compounds that contain carbon, hydrogen, and oxygen. They are the most abundant type of molecule in living organisms, and they play a vital role in many biological processes.

Answer 49

Carbohydrates

Question 50

Simplest carbohydrates; also known as single sugars

Answer 50

Monosaccharides

Question 51

Monosaccharides Greek monos = single; sacchar = sugar

Question 52

the most common monosaccharides

Answer 52

Glucose

Question 53

TRUE OR FALSE Hydrochloric acid (HCl) is an example of a strong acid

Answer 53

True

Question 53

Classification of monosaccharides depending on the Location of the carbonyl (C=O) group

Answer 53

1. Aldose → aldehyde sugars 2. Ketoses → ketone sugars

Question 53

Classification of monosaccharides depending on the Length of their carbon skeletons

Answer 53

* Trioses → are 3-carbon sugars * Pentoses → are 5-carbon sugars * Hexoses → are 6-carbon sugars

Question 54

Are double sugars, consisting of 2 monosaccharides joined by a glycosidic linkage, a covalent bond formed between 2 monossacharides by a dehydration reaction

Answer 54

Disaccharides

Question 55

Examples of disaccharides:

Answer 55

Maltose → Sucrose → glucose + fructose Lactose → glucose + galactose

Question 56

Are macromolecules, polymers with a few hundred to a few thousand monosaccharides joined by a glycosidic linkage

Answer 56

Polysaccharides

Question 57

2 Types of Polysaccharides:

Answer 57

1. Storage Polysaccharides 2. Structural Polysaccharides

Question 58

Plants store starch as granules within cellular structures known as plastids, which include chloroplasts

Answer 58

Starch

Question 59

A storage polysaccharide in animals usually stored mainly on liver & muscle cells

Answer 59

Glycogen

Question 60

A major component of the tough walls that enclose plant cells

Answer 60

Cellulose

Question 61

The carbohydrate used by anthropods to build their exoskeletons

Answer 61

Chitin

Question 62

Compounds that are hydrophobic, which explains why fats or oils don’t mix with water

Answer 62

Lipids

Question 63

3 Forms of lipids

Answer 63

1. Fats 2. Phospholipids 3. Steroids

Question 64

Constructed from 2 smaller molecules: glycerol and fatty acids.

Answer 64

Fats

Question 65

2 types of fats

Answer 65

1. Saturated Fat 2. Unsaturated Fat

Question 66

3 Functions of fats

Answer 66

1. Energy storage 2. Cushions vital organs 3. Insulates the body

Question 67

Many hormones are steroids produced from __________

Answer 67

cholesterol

Question 68

Cholesterol is synthesized in the ___________

Answer 68

liver

Question 69

2 structure of phospholipids

Answer 69

1. Hydrophilic head 2. Hydrophobic tails

Question 70

___________ biomolecules that are essential to all known forms of life

Answer 70

Nucleic Acids

Question 71

2 types of nucleic acids

Answer 71

1. deoxyribonucleic acid (DNA) 2. ribonucleic acid (RNA)

Question 72

___________ is the genetic material that organisms inherit from their parents

Answer 72

DNA

Question 73

Consist of a single polynucleotide chain

Answer 73

RNA

Question 74

The sugar connected to the nitrogenous bases in the nucleotide of RNA

Answer 74

Ribose

Question 75

The sugar connected to the nitrogenous bases in the nucleotide of DNA

Answer 75

Deoxyribose

Question 76

The bonds that connect the pyrimidine family and the purine family

Answer 76

hydrogen bonds

Question 77

type of covalent bond that links two monosaccharides together

Answer 77

Glycosidic bond

Question 78

type of covalent bond that is found in nucleic acids. Iis what holds the sugar-phosphate backbone of nucleic acids together.

Answer 78

phosphodiester bond

Question 79

Protein came from Greek word proteios meaning __________

Answer 79

“first place”

Question 80

Proteins -- Regulate metabolism by acting as catalysts that speed up chemical reactions

Answer 80

Enzymatic Proteins

Question 81

Proteins -- play a role in structural support Ex.: cocoons & webs, collagen & elastin, keratin

Answer 81

Structural Proteins

Question 82

Proteins -- storage of amino acids Ex.: ovalbumin, casein, seeds

Answer 82

Storage Proteins

Question 83

Proteins -- transport of other substances Ex.: hemoglobin

Answer 83

Transport Proteins

Question 83

Proteins -– coordnation of an organisms’ activities Ex.: insulin

Answer 83

Hormonal Proteins

Question 84

Proteins –- response of cell to chemical stimuli Ex.: receptors build into the membrane of nerve cell

Answer 84

Receptor Proteins

Question 85

Proteins -– for movement Ex.: actin & myosin, cilia & flagella

Answer 85

Contractile/ Motor Protein

Question 86

Proteins -–protections against diseases Ex.: antibodies

Answer 86

Defensive Proteins

Question 87

Proteins in the milk

Answer 87

casein