Topic 1 Key Concepts In BIO

Question 1

Picometre (pm)

Answer 1

A quantitative unit of length. One picometre is equal to × 10-12 metre.

Question 2

Plasmid

Answer 2

Loops of DNA found in the cytoplasm of prokaryotic cells.

Question 3

Prokaryotic cells

Answer 3

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

Question 4

Proteases

Answer 4

• Enzymes that break down proteins into amino acids.

Question 5

Protein

Answer 5

A large molecule that is synthesised from amino acids.

Question 6

Rate of reaction

Answer 6

The speed at which reactants are converted into products.

Question 7

Ribosomes

Answer 7

Ribosomes - Sub-cellular structures that are the site of protein synthesis.

Question 8

Specialised cell

Answer 8

A cell that has a structure which makes it adapted to its function.

Question 9

Sperm cell

Answer 9

Sperm cell - A specialised male sex cell that is involved in reproduction.

Question 10

Vacuole

Answer 10

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

Question 11

Mitochondria

Answer 11

An organelle that is the site of respiration.

Question 12

Nucleus

Answer 12

Nucleus - An organelle found in most eukaryotic cells that contains the genetic material of the cell and controls the activities of the cell.

Question 13

Osmosis

Answer 13

The diffusion of water molecules from a region of high water concentration to a region of lower water concentration across a partially permeable membrane.
.

Question 14

Plasmid

Answer 14

Plasmid - Loops of DNA found in the cytoplasm of prokaryotic cells.

Question 15

Enzyme

Answer 15

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

Question 16

Eukaryotic

Answer 16

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

Question 17

Flagella

Answer 17

A long hair-like structure found on bacterial cells that is used for cell movement.

Question 18

Haploid

Answer 18

A cell that contains a single copy of each chromosome (i.e. half the number of chromosomes).

Question 19

Iodine test

Answer 19

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

Question 20

Light microscopes

Answer 20

Light microscope - A type of microscope that uses a series of lenses to magnify the visible light reflecting off a specimen. It has a lower magnification and resolution than an electron microscope.

Question 21

Lipases

Answer 21

Enzymes that break down lipids into fatty acids and glycerol.

Question 22

Lipid

Answer 22

Lipid - A large molecule that is synthesised from fatty acids and glycerol.

Question 23

Magnification

Answer 23

Magnification - The number of times bigger an image appears compared to the original object, calculated using the formula:

Question 24

Diffusion

Answer 24

The net spreading out of particles from a high concentration to a lower concentration (down their concentration gradient).

Question 25

Diploid cell

Answer 25

Diploid cell - A cell that contains two copies of each chromosome (i.e. a full set of chromosomes).

Question 26

Egg cell

Answer 26

A specialised female sex cell involved in reproduction.

Question 27

Electron microscope

Answer 27

Electron microscope - A type of microscope that uses a beam of electrons, focused using magnets, to produce an image of a specimen. It has a greater magnification and resolution than a light microscope.

Question 28

Emulsion test

Answer 28

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

Question 29

Active transport

Answer 29

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 30

Benedict’s test

Answer 30

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

Question 31

Biuret test

Answer 31

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

Question 32

Carbohydrate

Answer 32

Carbohydrate - A large molecule that is synthesised from simple sugars.

Question 33

Cell

Answer 33

The basic building block of all living organisms.

Question 34

Cell membrane

Answer 34

A partially permeable barrier that surrounds the cell.

Question 35

Cell wall

Answer 35

An outer layer made of cellulose that strengthens plant cells.

Question 36

Chloroplast

Answer 36

An organelle that is the site of photosynthesis.

Question 37

Chromosomes

Answer 37

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

Question 38

Cilia

Answer 38

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

Question 39

Active site

Answer 39

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

Question 40

Active transport

Answer 40

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.