Topic 1 - Key terms

Question 1

Define an acrosome

Answer 1

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

Question 2

Define an active site

Answer 2

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

Question 3

Define active transport

Answer 3

The movement of substances from a low concentration to a high concentration

Question 4

Define binedict’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

Define biuret test

Answer 5

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

Question 6

Define calorimetry

Answer 6

A method of measuring heat transfer during a chemical reaction

Question 7

Define carbohydrasses

Answer 7

Enzymes that break down carbohydrates into simple sugars

Question 8

Define a carbohydrate

Answer 8

A large molecule that is synthesised from simple sugars

Question 9

Define a cell

Answer 9

The basic building block of all living organisms

Question 10

Define a cell membrane

Answer 10

A partially permeable barrier that surrounds the cell

Question 11

Define a cell wall

Answer 11

An outer layer made of cellulose that strengthens plant cells

Question 12

Define chloroplasts

Answer 12

An organelle that is the site of photosynthesis

Question 13

Define a chromosome

Answer 13

A long, coiled molecule of DNA that carries genetic information in the form of genes

Question 14

Define cilia

Answer 14

Hair-like structures found on ciliated epithelial cells which pass substances across the surface of the tissue in one direction

Question 15

Define a ciliated epithelial cell

Answer 15

A type of epithelial cell that lines the surface of structures such as the respiration tract and uterus

Question 16

Define a concentration gradient

Answer 16

The difference in concentration between 2 areas

Question 17

Define denaturing

Answer 17

The permanent change in the shape of an enzyme’s active site that prevents the binding of a substrate

Question 18

Define diffusion

Answer 18

The movement of particles from a high concentration to a low concentration

Question 19

Define a diploid cell

Answer 19

A cell that contains 2 copies of each chromosome

Question 20

Define an egg cell

Answer 20

A specialised female sex cell involved in reproduction

Question 21

Define an electron microscope

Answer 21

A type of microscope that uses a beam of electrons, focused using magnets to produce an image of a specimen

Question 22

Define the emulsion test

Answer 22

A chemical test that produces a cloudy emulsion when performed on lipids

Question 23

Define an enzyme

Answer 23

A biological catalyst that increases the rate of reactions in living organisms

Question 24

Definea eukrayotic cell

Answer 24

A type of cell found in plants and animals that contain a nucleus

Question 25

Define the flagella

Answer 25

A whip-like tail attached to bacteria that allow bacteria cells to move

Question 26

Define a haploid cell

Answer 26

A cell that contains a single copy of each chromosome

Question 27

Define the iodine test

Answer 27

A chemical test that produces a blue/ black colour when iodine solution is added to a sample containing starch

Question 28

Define a light microscope

Answer 28

A type of microscope that uses a series of lenses to magnify the visible light reflecting off a specimen

Question 29

Define lipases

Answer 29

Enzymes that break down lipids into fatty acids and glycerol

Question 30

Define a lipid

Answer 30

A large molecule that is synthesised from fatty acids and glycerol

Question 31

Define the lock and key hypothesis

Answer 31

A theory that describes how substrates must be the correct shape to fit the active site of an enzyme

Question 32

Define magnification

Answer 32

The number of times bigger an image appears compared to the original object

Question 33

Define a micrometer

Answer 33

A quantative unit of length

Question 34

Define a millimeter

Answer 34

A quantative unit of length

Question 35

Define mitochondria

Answer 35

Site of respiration

Question 36

Define a nanometer

Answer 36

A quantative unit of length

Question 37

Define a nucelus

Answer 37

Contains genetic material of the cell and controls the activities of the cell

Question 38

Define an organelle

Answer 38

A specialised structure found inside a cell

Question 39

Define osmosis

Answer 39

The movement of water molecules from a high water concentration to a low water concentration across a semi-permeable membrane

Question 40

Define percentage change in mass

Answer 40

The proportion of the mass of a substance that has changed over a set period

Question 41

Define a picometer

Answer 41

A quanitative unit of length

Question 42

Define a plasmid

Answer 42

Loops of DNA found in the cytoplasm of prokaryotic cells

Question 43

Define a prokaryotic cells

Answer 43

A type of cell found in bacteria that does not contain a nucleus

Question 44

Define proteases

Answer 44

Enzymes that break down proteins into amino acids

Question 45

Define protein

Answer 45

A large molecule that is synthesised from amino acids

Question 46

Define the rate of reaction

Answer 46

The speed at which reactants are converted into products

Question 47

Define resolution

Answer 47

The smallest distance between two objects that can be distinguised

Question 48

Define ribosomes

Answer 48

Sub-cellular structures that are the site of protein synthesis

Question 49

Define a specialised cell

Answer 49

Cells that have a specific structure to allow them to do their specific function

Question 50

Define specificity

Answer 50

Describes the ability of an enzyme to catalyse only a particular reaction or set of reactions in which a specific substrate fits the active site of the enzyme

Question 51

Define a sperm cell

Answer 51

A specialised male sex cell that is involved in reproduction

Question 52

Define a vacuole

Answer 52

A organelle found in plant cells which stores cell sap and supports the cell