Lecture 11

Question 1

metabolism

Answer 1

the synthesis (creation) of molecules, as well as the breakdown of molecules.

Question 2

Atom

Answer 2

• For every proton (+) there is a corresponding electron (-)
• an atom should be electrically neutral
• atoms are held together by electrical forces of atraction called chemical bonds

Question 3

Energy feilds

Answer 3

first feild: electrons
2nd feild: electrons
3rd feild: electrons

Question 4

What happens if an outer feild is not filled

Answer 4

• atroms like to fill them with electrons

eg: sodium atom and a chlorine atom = molecule = sodium chloride

Question 5

Ions

Answer 5

An atom with a + or - charge is called an ION

Question 6

How to tell if an atom is + or - charge

Answer 6

• If an atom gains an electron it will acquire an overall negative charge
• If an atom loses an electron (sodium) it acquires an overall positive charge

Question 7

chemical bonding

Answer 7

involves the donating, receiving or sharing of electrons between atoms,

• energy is needed to form these bonds
• however when bonds are broken energy is released

Question 8

cells

Answer 8

• the union of two or more atoms forms a molecule

- this process occurs in a cell

Question 9

Parts of a cell:

Answer 9

1- cell membrane
2- nucleus
3- cytoplasm

Question 10

cell membrane

Answer 10

• Encloses the contents of the cell – protective barrier

- Regulates the passage of substances in and out of the cell

Question 11

Nucleus

Answer 11

Contains genetic components

Question 12

Cytoplasm

Answer 12

Contains organelles

Question 13

Enzymes

Answer 13

• Enzymes are proteins that speed up cellular chemical reactions.
• Enzymes assist in the breakdown of some food stuffs.

Question 14

organic vs inorganic

Answer 14

carbon - organic

does not contain carbon = inorganic

Question 15

Functions of enymes

Answer 15

1. Temperature
2. Hydrogen ions – affects Ph
   affect the ability of enzymes to work.
   - Lower temperature decrease enzyme activity – decreases metabolism
   - Increased temperature increases enzyme activity – increases metabolism.
   - High acidity (caused by increases in H+ ) usually inhibits enzyme activity

Question 16

hydrogen ions and exercising

Answer 16

if you create too many hydrogen ions in the body it affects the Ph which will then affect the enzyme activity and stops it, therefore need to stop exercising

Question 17

Enzyme process:

Answer 17

Step 1
The active sites of the enzyme and substrate fit together.
Step 2
The enzyme catalyses the chemical reaction.
Step 3
An end-product is produced.
Step 4
The enzyme is now free to start the process again.

Question 18

Co enzymes

Answer 18

• acts as assistants to enzymes
  Two important coenzymes are:
• Nicotinamide adenine dinucleotide (NAD)
• Flavin adenine dinucleotide (FAD)
• These two coenzymes act like taxis and carry H to a special pathway in order to be processed so to produce energy

Question 19

Anabolism:

Answer 19

• When the atom or molecules combine to form a new and larger molecule
• This process is also called a synthesis reaction
• Synthesis means combinations

Question 20

Catabolism

Answer 20

When larger molecules are broken down to smaller molecules or atoms

Question 21

Hydrolysis

Answer 21

When water is added to a complex organic molecule
It is degraded/catabolised to two simpler molecules.
eg: sucrose is converted to a glucose and a fructose molecule with the addition of water (catabolic)

Question 22

Condensation

Answer 22

Reverse of hydrolysis
= two or more simple molecules combine to
form a complex molecule
and in the process lose a water molecule. (anabolic)
eg: 2 simple glucose molecules lose water to for a complex maltose molecule

Question 23

energy

Answer 23

: the capacity to perform work

• adenosine triphosphate (ATP)
• limited reserves in the body (80-100g)
• remade from chemical energy

Question 24

Chemical energy comes from 3 sources:

Answer 24

1- CHO
2- lipids/fats
3- protein