Biology Ch1. Revision

Question 1

Magnification

Answer 1

the degree to which something is or can be magnified.

Question 2

Resolution

Answer 2

The level of quality in an image

Question 3

IAM triangle

Answer 3

Image size = magnification x actual size
Magnification = image size divided by actual size
Actual size = image size divided by magnification

Question 4

Nucleus

Answer 4

‘Control center’ of cell containing DNA.

Question 5

Cytoplasm

Answer 5

Liquid in cell where chemical reactions take place

Question 6

Cell membrane

Answer 6

Outer layer of protection in a cell. In a plant cell it is surrounded by a cell wall.

Question 7

Mitochondria

Answer 7

Component of cell where chemical reactions takes place.

Question 8

Ribosomes

Answer 8

Aspect of cell responsible for protein synthesis

Question 9

Cell wall

Answer 9

Outer layer of plant cell. Animal cells only have a cell membrane

Question 10

Vacuole

Answer 10

Food storage in a cell. Usually permanent in plant cells but temporary in animal cells.

Question 11

Chloroplasts

Answer 11

Aspect of a plant cell responsible for photosynthesis.

Question 12

Eukaryotic cells

Answer 12

Plant cells and animal cells are both eukaryotic because their cells contain a nucleus. A eukaryote is an organism which contains mainly eukaryotic cells.

Question 13

Prokaryotic cells

Answer 13

Cells, such as bacterial and fungal, that contain no nucleus. A prokaryote is an organism that contains mainly prokaryotic cells.

Question 14

Plasmids

Answer 14

The DNA of a bacterial cell, however is also found in some eukaryotes

Question 15

Order of magnitude

Answer 15

Order of size

Question 16

Nerve cell adaptations

Answer 16

Contain branches allowing the cell to span over a wider volume.

Question 17

Muscle cell adaptations

Answer 17

Cells merge together to form muscles that can contract

Question 18

Sperm cells adaptations

Answer 18

‘Tail’ allows them to move and shape means they can burrow into the egg cell.

Question 19

Root hair cell adaptations

Answer 19

Large surface area to speed up osmosis and allow the plant to receive water at a faster rate.

Question 20

Xylem cells

Answer 20

Responsible for transpiration. Involved in the movement of water through a plant from its roots to its leaves.

Question 21

Phloem cells

Answer 21

Responsible for translocation. This is the movement of food substances from the stems to growing tissues and storage tissues.

Question 22

Diffusion

Answer 22

Movement of particle from a region of high concentration to a region of low concentration.

Question 23

Rate of diffusion

Answer 23

Rate at which a particle moves from an area of high to low concentration.

Question 24

Dilute

Answer 24

Substance that has been diluted by a neutral substance such as water. Eg. Ribena

Question 25

Concentrated

Answer 25

Substance that has not been diluted by a neutral substance such as water. Eg. Bleach

Question 26

Osmosis

Answer 26

Movement of H2O particles from an area of high concentration to an area of low concentration across a membrane.

Question 27

Crenated

Answer 27

Animal cell placed in a concentrate substance loses water via osmosis and shrinks and dries.

Question 28

Lysis

Answer 28

Animal cell placed in dilute solution gains water through osmosis to the point where it expands so much that the cell membrane ruptures and the cell effectively explodes.

Question 29

Plasmolysis

Answer 29

Plant cell placed in concentrated solution loses water due to osmosis and dries out, with the cell membrane peeling from the inside of the cell wall.

Question 30

Turgid

Answer 30

When placed in a dilute solution the plant cell gains water through osmosis and begins to swell, however it does not rupture because unlike the animal cell it has a cell wall.

Question 31

DNA structure

Answer 31

DNA is a polymer made up of 2 strands joined together. It is a double stranded, double helix molecule.

Question 32

Chromosome

Answer 32

Chromosomes are made up of thousands of genes. There are 46 cheomosomes in each cell.

Question 33

Gene

Answer 33

A gene is coding regions in the DNA that make all the proteins in the body. (They make up who we are).

Question 34

Allele

Answer 34

A variation of a gene found in the parent that could be inherited by offspring.

Question 35

Dominant allele

Answer 35

If there is 1 dominant allele, the offspring will get that gene.

Question 36

Recessive allele

Answer 36

If there is two recessive alleles (one from each parent), this will be the gene inherited by the offspring.

Question 37

Homozygous

Answer 37

If there are 2 of the same alleles, the person has homozygous alleles

Question 38

Heterozygous

Answer 38

If there is different alleles, the alleles are heterozygous.