Key concepts in Biology

Question 1

Acrosome

Answer 1

An organelle in the tip of a sperm that contains enzymes which digest the egg cell membrane.

Question 2

Active site

Answer 2

A specific region on an enzyme where the substrate binds and the reaction takes place.

Question 3

Active transport

Answer 3

The movement of substances from a low concentration to a higher concentration (against the concentration gradient) across a membrane, with the use of energy from respiration.

Question 4

Benedict’s test

Answer 4

A chemical test used to test for reducing sugars that produces a different colour based on the amount of reducing sugar present.

Question 5

Biuret test

Answer 5

A chemical test that produces a purple colour when it is added to a solution containing protein.

Question 6

Microscopes- Resolution

Answer 6

The smallest distance that can still be seen as two points

Question 7

A = actual size (of cell)
M = magnification
I = image size

Answer 7

I / M
I / A
A * M

Question 8

Plant cell

Answer 8

Chloroplast
Cell wall
Vacuole
Cytoplasm
Membrane
Nucleus
Ribosomes
Mitochondria

Question 9

Animal cell

Answer 9

Cytoplasm
Membrane
Nucleus
Ribosomes
Mitochondria

Question 10

Cell membrane

Answer 10

Controls what enters and what leaves the cell

Question 11

Nucleus

Answer 11

Contains DNA and controls cell activity

Question 12

Cytoplasm

Answer 12

Where chemical reactions happen

Question 13

Ribosomes

Answer 13

Where protein is made

Question 14

Mitochondria

Answer 14

Where aerobic respiration happens

Question 15

Cell wall

Answer 15

Provides support and maintains shape

Question 16

Vacuole

Answer 16

Provides support and contains cell sap

Question 17

Chloroplasts

Answer 17

Site of photosynthesis

Question 18

Prokaryotic cells

Answer 18

The capsule
Cell wall
Plasma membrane
Ribosomes
Pili
Nucleoid
Flagella

Question 19

The capsule

Answer 19

The protective barrier against white blood cells

Question 20

Plasma membrane

Answer 20

Allows things to enter and leave.

Question 21

Pili

Answer 21

Allows bacteria to attach to other cells

Question 22

Nucleoid

Answer 22

A loop of loosen DNA

Question 23

Flagella

Answer 23

Tail enables it to move

Question 24

The difference between Prokaryotic cells and Eukaryotic cells (e.g plant and animal cells)

Answer 24

Prokaryotic cells do not have a nucleus or membrane bound organells

Question 25

Transporting substances

Answer 25

Diffusion - The movement of a substance from an area of high concentration to low concentration HIGH -> LOW Osmosis — The diffusion of water, across a semi-permeable membrane, from a dilute area to a more concentrated area LOW—> HIGH

Question 26

Active transport

Answer 26

The movement of ions against the concentration gradient, this means the concentration of the ion is lower outside the cell than inside the cell. This requires energy

Question 28

Mitosis - stages of the cell cycle

Answer 28

Interphase Prophase Metaphase Anaphase Telophase Cytokinesis

Question 29

Interphase

Answer 29

The DNA in the cell is copied. Sub-cellular parts are also copied

Question 30

Prophase

Answer 30

The membrane around the nucleus breaks down

Question 31

Metaphase

Answer 31

The chromosomes line up in the middle of the cell

Question 32

Anaphase

Answer 32

Each of the chromosomes x-shapes splits to form single chromosomes. The single chromosomes move away from each other

Question 33

Telophase

Answer 33

The single chromosomes arrive at opposite ends of the cell. The membranes around each nucleus start to form again

Question 34

Cytokinesis

Answer 34

The cytoplasm of the cell is seperated as a cell membrane dividers the cell into two daughter cells