Module 2- Key Words

Question 1

Magnification

Answer 1

The degree to which the size of an image is larger than the object itself

Question 2

Staining

Answer 2

The process which helps reveal or distinguish different features

Question 3

Cytoskeleton

Answer 3

The network of protein fibres found within cells that give structure and shape to the cell

Question 4

Organelle

Answer 4

A particular structure of a cell which has a specialised/specific function

Question 5

Phospholipid Bilayer

Answer 5

The basic structural components of plasma/ cell surface membranes, consisting of two layers of phospholipid

Question 6

Fluid Mosaic Model

Answer 6

Model of cell surface/ plasma membrane structure

Question 7

Cell signalling

Answer 7

Cells communicate with one another by signals eg. Hormones to help them work together and coordinate their actions

Question 8

Diffusion

Answer 8

The net movement of molecules from a region of high partial pressure of that molecule to a region of lower partial pressure of that molecule down a concentration gradient. This is a passive process

Question 9

Facilitated Diffusion

Answer 9

The net movement of molecules or ions across a membrane from a region of high concentration of that molecule to a region of lower concentration of that molecule down a concentration gradient through carrier proteins (large molecules) or channel proteins (ions). This is a passive process

Question 10

Active transport

Answer 10

The movement of molecules or ions across a membrane from a religion of low concentration to a region of high concentration of that molecule , against the concentration gradient. This process uses ATP to drive the protein pumps within the membrane

Question 11

Osmosis

Answer 11

The net movement of water molecules from a region of high water potential to an area of lower water potential, down the water potential gradient across a partially permeable membrane. This is a passive process

Question 12

Solute

Answer 12

A solid that dissolves in a liquid

Question 13

Solvent

Answer 13

A liquid that dissolves solids

Question 14

Solution

Answer 14

A liquid containing dissolved solids

Question 15

Cell cycle

Answer 15

Describes the events that take place as one parent cell divides to produce two new daughter cells which then each grow to full size

Question 16

Mitosis

Answer 16

The process of nuclear division where two genetically identical nuclei are formed from one parent cell nucleus

Question 17

Resolution

Answer 17

The ability to be able to distinguish between two objects which are close together

Question 18

Clones

Answer 18

Genetically identical cells or organisms derived from one parent

Question 19

Differentiation

Answer 19

The changes occurring in cells of a multicellular organism so that each different type of cell becomes specialised to perform a specific function

Question 20

Tissue

Answer 20

A group of similar specialised cells working together to perform a common function

Question 21

Organ

Answer 21

A collection of tissues that work together to carry out a common function

Question 22

Stem cells

Answer 22

Cells that are not differentiated and are capable of mitosis and differentiation to become other cell types

Question 23

Metabolism

Answer 23

In the sum total of all the biochemical reactions taking place in the cells of an organism

Question 24

Polysaccharides

Answer 24

Are polymers of monosaccharides. They consist of hundreds or thousands of monosaccharide monomers bonded together to form a single large molecule

Question 25

Hydrolysis

Answer 25

Breaking of a covalent bond using a water molecule

Question 26

Condensation

Answer 26

Forming a bond which releases a water molecule

Question 27

Primary structure

Answer 27

Sequence or order of amino acids in a polypeptide chain

Question 28

Secondary structure

Answer 28

The coiling or folding of the polypeptide into an alpha helix or beta pleated sheet held together with hydrogen bonds between amino acids

Question 29

Tertiary structure

Answer 29

The final 3D shape of the protein. The shape is held in place with hydrogen bonds, ionic bonds between oppositely charged r groups, disulphide bridges and hydrophobic and hydrophilic interactions

Question 30

Quaternary structure

Answer 30

Made up of more than one polypeptide chain joined together to make the final functional protein

Question 31

Lipids

Answer 31

Substances that dissolve in organic solvents like alcohol but not water

Question 32

Saturated fatty acids

Answer 32

Fatty acids with no double bonds in the hydrocarbon chain

Question 33

Unsaturated fatty acids

Answer 33

Fatty acids with at least one double bond in the hydrocarbon chain

Question 34

Triglyceride

Answer 34

3 fatty acids joined to a glycerol molecule with 3 ester bonds

Question 35

Nucleotides

Answer 35

Monomers of nucleic acids. Made of a phosphate group, pentose sugar and a nitrogenous base

Question 36

Gene

Answer 36

A length of DNA that codes for a specific protein

Question 37

Enzyme

Answer 37

Biological catalysts which reduce the activation energy required for a reaction to take place. They are protein molecules

Question 38

Activation energy

Answer 38

The required amount of energy for a chemical reaction to take place

Question 39

Active site

Answer 39

A region on the surface of an enzyme molecule where a substrate can bind and where the reaction takes place

Question 40

Enzyme specificity

Answer 40

One enzyme’s active site is complementary in shape to only one substrate molecule

Question 41

Catalyst

Answer 41

A molecule which speeds up a chemical reaction but remains unchanged and is not used up in the reaction

Question 42

Extracellular

Answer 42

Chemical reactions taking place outside of the cell

Question 43

Intracellular

Answer 43

Chemical reactions taking place inside of the cell

Question 44

Denaturation

Answer 44

When the active site of an enzyme changes shape due to the breaking of the bonds, losing its tertiary structure and complementary shape to the substrate