Structure and functions in living organisms

Question 1

what does a plant cell have that an animal cell doesn’t have

Answer 1

Chloroplast
vacuole
cell wall

Question 2

What is the function of the mitochondria

Answer 2

Site of respiration
releases energy for the cell

Question 3

what is the function of the
cell membrane

Answer 3

Controls what enters and exits the cell

Question 4

what is the function of cytoplasm

Answer 4

where chemical/metabolic reactions occur

Question 5

What is the function of the nucleus.

Answer 5

Controls the activity of the cell using genes/ DNA

Question 6

What is the function of the ribosomes.

Answer 6

where proteins are made
site of the protein synthesis

Question 7

What is the function of the vacuole and what does it contain

Answer 7

Contains cell sap
helps keep the cells structure

Question 8

What do chloroplast contain

Answer 8

Contains chlorophyll a green pigment gives the plant it’s colour

Question 9

what is the function of the cell wall and what is it made off

Answer 9

made of cellulose helps keep the plant cell shape/ structure

Question 10

what chemical elements are present in Carbohydrates

Answer 10

CHO
Carbon, oxygen, hydrogen

Question 11

what chemical elements are present in Protein

Answer 11

CHON
Carbon, oxygen, hydrogen, nitrogen

Question 12

what chemical elements are present in lipids (fats and oils)

Answer 12

CHO
Carbon, hydrogen, oxygen

Question 13

describe the structure of carbohydrates

Answer 13

long chain of simple sugars

Question 14

what is a simple sugar of carbohydrates

Answer 14

Monosaccharide

Question 15

examples of carbohydrates(monosaccharide)

Answer 15

glucose
fructose
galactose

Question 16

examples of disaccharide carbohydrates

Answer 16

Maltose
lactose
sucrose

Question 17

examples of Polysaccharide carbohydrates

Answer 17

starch
glycogen
cellulose

Question 18

what are examples of monomers for lipids

Answer 18

glycerol and fatty acids

Question 19

what are most Lipids in the body made up of

Answer 19

Triglycerides

Question 20

what are examples of polymers for lipids

Answer 20

Triglyceride

Question 21

what are monomers for Protein

Answer 21

amino acids

Question 22

what are polymers for protein

Answer 22

polypeptide/protein

Question 23

what are proteins

Answer 23

long chains of amino acids

Question 24

what is the role of an enzyme

Answer 24

A biological molecule which speeds up the rate of reaction without being used up itself by lowering the energy required

Question 25

what happens to an enzyme as temperature increases

Answer 25

As temperature increase so does the rate of reaction up to a certain point.
kinetic energy of molecules increases=more collisions
optimum temp is when enzymes work rate is the highest
After optimum temp enzyme denatures(active site shape changes)

Question 26

when the enzyme denatures what happens to it

Answer 26

the shape changes
active site changes

Question 27

What happens to an enzyme as pH changes

Answer 27

If it is too high or too low the Ph interferes with the bonds holding the enzyme together
- This changes the shape of the active site
- enzyme denatures
- Active site changes
- No ESC formed
- All enzymes have an optimum pH that they work best at , this usually a pH Level of 7

Question 28

all enzymes have an ________ pH __________ of usually ___________

Answer 28

all enzymes have an optimum pH level of usually 7

Question 29

Describe the practical investigation on how enzyme activity can be affected by the change in temp

Answer 29

• Add 5cm3 starch solution to a test tube and heat to a set temperature using beaker of water with a Bunsen burner
• Add a drop of Iodine to each of the wells of a spotting tile
• Use a syringe to add 2cm3 amylase to the starch solution and mix well
• Every minute, transfer a droplet of solution to a new well of iodine solution (which should turn blue-black)

-Repeat this transfer process until the iodine solution stops turning blue-black (this means the amylase has broken down all the starch)

-Record the time taken for the reaction to be completed

-Repeat the investigation for a range of temperatures (from 20°C to 60°C)

Question 29

What is the process of diffusion

Answer 29

Diffusion is the random net movement of particles from an area of higher concentration to an area of lower concentration

Question 29

What is the process of Osmosis

Answer 29

Osmosis is the net movement of free water molecules from an area of high water concentration/pointential to an area of low water concentration across a partially permeable membrane

Question 29

what are factors which affect movement of substances

Answer 29

• surface area : volume ratio
• short diffusion distance
• Large blood supply to maintain concentration gradient ( only affects diffusion and osmosis not active transport)
• Temperature (as the particles in the substance get warmer they have more energy - so they move faster . This means as temperature increases substance moves in and out of cell faster.

Question 29

Describe the investigation for living organisms on osmosis

Answer 29

• cut up a potato into identical cylinders
• get some beakers with different sugar levels
• one with pure water
• one with a very high concentration of sugar solution
  then have a few other beakers with concentrations in between
• measure the initial length of the cylinders
• leave for around half-hour
• measure the final length
• if the cylinders have drawn in water via osmosis they will be a bit longer
• if they have shrunk then they have lost water via osmosis

Question 30

What is the process of active transport

Answer 30

Active transport is the movement of molecules from an area of low concentration to an area of high concentration using ATP (goes against the concentration gradient)