The Molecules Of Life

Question 1

7 characteristics of life

Answer 1

-Composed of cells
-Diff levels organization
-use energy
-respond to env.
-grow and develop
-reproduce
-adapt to env.

Question 2

Organic vs inorganic

Answer 2

Carbon based molecules =organic
Non - carbon based molecules = inorganic
(Water, oxygen, ammonia, mineral salts)

Question 3

Roles of water

Answer 3

Temp regulation
Form and support
Transport medium
Lubricating agent
Solvent
Reactant

Question 4

Temp regulation
(Roles of water)

Answer 4

• sweat glands produce perspiration which cools down body as it evaporates
  -plants cooled down by loss of water during transpiration (plant sweat)

Question 5

Form and support
(Role of water)

Answer 5

• Hydrostatic skeleton
• plants keep shape Bc of water pressure

Question 6

Transport medium
(Role of water)

Answer 6

• water, main constituent in blood, enables :
  Blood cells
  Hormones
  Dissolved gases
  Electrolytes
  Nutrients
  To be transported around body

Question 7

Lubricating agent
(Role of water)

Answer 7

• main constituent of saliva
  -helps w :
  Swallowing
  Chewing
  -keeps eyes lubricated

Question 8

Solvent
(Role of water)

Answer 8

-Universal solvent for biological chemicals
-medium for chemical reactions

Question 9

Reactant
(Role of water)

Answer 9

-during hydrolysis reactions, water added to the reaction to break down large molecules
-water can be split into hydrogen & oxygen for chemical reactions such as photosynthesis

Question 10

Function of nitrogen in animals and plants

Answer 10

Imp for :
-synthesis of protein farming
-formation of chlorophyll
-forms part of nucleotides in RNA & DNA

Question 11

Deficiency diseases in plants and animals due to a lack of nitrogen

Answer 11

In humans/animals
-poor growth
-reduced growth in organs

In plants
-Chlorosis in older leaves

Question 12

Functions of sulphur in plants and animals

Answer 12

In animals
-in proteins
-co-enzymes + insulin hormone
In plants
-promotes root developement

Question 13

Products of a sulphur deficiency in plants max animals

Answer 13

Animals
-Poor growth

Plants
-Poor root development
-Young leaf chlorosis

Question 14

Functions of Magnesium in plants and animals

Answer 14

In animals
-muscle contractions + nervous system
-activates enzymes

In plants
Essential chlorophyll component

Question 15

Deficiency diseases Bc of a lack of magnesium in plants and animals

Answer 15

In plants
Chlorosis betw older leaf veins

In animals/humans
Poor growth

Question 16

Function of phosphorus in plants and animals

Answer 16

-Bone and teeth formation
-Part energy carrier
-Component of RNA + DNA
-Found in phospholipids of cell memebranes

Question 17

Deficiency diseases due to a lack of phosphorus in plants and animals

Answer 17

Humans
-malfunctioning muscles/nerves
-rickets

Plants
-poor root growth
-brown spots on leaves

Question 18

Function of sodium in plants and animals

Answer 18

-maintains osmotic and neutral balance of body fluids
-osmoregulation in kidneys, secretion for stomach acid
-nerve and muscle function

Question 19

Deficiency diseases due to a lack of sodium in humans and plants

Answer 19

Humans
-nausea, vomiting, lethargy, death

Plants
-Reduced growth

Question 20

Function of Calcium in plants and animals

Answer 20

-found in middle lamella of plant (lamella = a layer cementing together the primary cell walls of two adjoining plant cells)
-bone structure
-teeth
-cell membrane permeability
-ions needed for blood clotting

Question 21

Deficiency diseases due to a lack of calcium in plants and animals

Answer 21

Humans
-Rickets
-delayed clotting

Plants
-young Chlorosis
-poor root growth

Question 22

Function of iron in plants and animals

Answer 22

-chlorophyll synthesis
-component of electron carriers in respiration and photosynthesis

Question 23

function of iodine in plants and animals

Answer 23

• found in the hormone thyroxin
  (thyroid gland)

Question 24

deficiency diseases found caused by a lack of potassium in humans and plants

Answer 24

humans
-nerve and muscle malfunction
- cardiac irregularities

plants
- reduced flower and fruit

Question 25

deficiency diseases found caused by a lack of iodine in humans and plants

Answer 25

humans
- cretinism in children (stupid)
- goitre in adults (swelling in throat)

Question 26

potassium functions in humans and plants

Answer 26

• growth of fruit and flowers
• function of nerves and muscles