Key Concepts In Biology ( 1 )

Question 1

What are eukaryotic cells + eg

Answer 1

Have a nucleus

Plant and animal cells

Question 2

What are prokaryotic cells + eg

Answer 2

No nucleus

Bacteria

Question 3

Nucleus

Answer 3

Contains genetic material arranged into chromosomes

Question 4

Cytoplasm

Answer 4

Contains enzymes

Where chemical reactions take place

Question 5

Cell membrane

Answer 5

Semi permeable membrane controls what enters and exits

Question 6

Mitochondria

Answer 6

Respiration takes place

Question 7

Ribosomes

Answer 7

Synthesise proteins

Question 8

Cell wall

Answer 8

Made of cellulose strength

Question 9

Vacuole

Answer 9

Maintains internal pressure

Question 10

Chloroplasts

Answer 10

Where photosynthesis occurs

Contain chlorophyll

Question 11

Flagellum

Answer 11

Move bacteria away from harmful toxins and towards oxygen

Question 12

What are the 3 specialised cells

Answer 12

Egg
Sperm
Ciliated epitherelia cells

Question 13

Explain how specialised cells are used for reproduction

Answer 13

Egg cell fuses with sperm cell to create fertilised egg which develops into embryo
Both of these are haploid to create a diploid cell

Question 14

Egg cell functions

Answer 14

Carry female dna and nourish developing embryo

Question 15

Functions of sperm cell

Answer 15

Transport males dna to female egg

Long tail to swim to egg

Question 16

Cilliated epithelia cells

Answer 16

Line the surface of organs

Move substances along a direction by cilia

Question 17

Total magnification equation

Answer 17

Eyepiece lens x objective lens

Question 18

What are enzymes used for

Answer 18

Biological catalyst

Question 19

Explain enzymes active site

Answer 19

For an enzyme to work the substrate must fit in active site

This is called ‘ lock and key ‘

Question 20

What happens to enzyme if it’s too hot

Answer 20

Denatures due to optimum temperature

Question 21

What does the core practical on investigating effect on ph enzyme do

Answer 21

Enzyme analyse cataylises breakdown of starch using iodine . If startch is present it will go black.

Question 22

Rate of reaction

Answer 22

1000 | time

Question 23

What are the 3 big molecules

Answer 23

Proteins , lipids , carbohydrates

Question 24

Why are molecules digested

Answer 24

Allow them to be absorbed into the blood stream so they can pass into cells of body

Question 25

What do enzymes convert carbohydrates into

Answer 25

Simple sugars

Analyse —> starch

Question 26

What do protease convert proteins into

Answer 26

Amino acids

Question 27

What do lipases convert lipids into

Answer 27

Fatty acids

Question 28

What is used to store energy in animals

Answer 28

Glycogen

Question 29

What’s diffusion

Answer 29

Movement of partials from area of high to low concentration

Question 30

What’s osmosis

Answer 30

Movement of water to high to low concentration

Question 31

What’s the osmosis experiment

Answer 31

Prepare sucrose solution from pure to concentrated
Use potato skins and place in each
Record mass after 40 mins
Calculate percentage change

Question 32

What’s percentage change

Answer 32

Final mass - initial mass

Initial mass X 100