B1-Cell-level systems

Question 1

DNA structure

Answer 1

Double helix, made of nucleotides,polymer

Question 2

DNA bases

Answer 2

Adenine,guanine,cytosine and thymine

Question 3

DNA base pairs

Answer 3

A and T

C and G

Question 4

Enzymes

Answer 4

Large protein molecules,catalysts,specific to one reaction

Question 5

Lock and key hypothesis

Answer 5

Active site specific to only one substrate

Question 6

Factors affecting rate of enzyme reactions

Answer 6

1-temperature 
2-pH
3-substrate concentration 
4-enzymes concentration 
(pH too high or too hot, enzymes will denature)

Question 7

Catalyst

Answer 7

Something that speeds up a reaction without being used up itself

Question 8

Enzyme- carbohydrates->sugars

Answer 8

Carbohydrase

Question 9

Enzyme- proteins-> amino acids

Answer 9

Protease

Question 10

Enzyme- Lipids->fatty acids + glycerol

Answer 10

Lipase

Question 11

Respiration equation

Answer 11

Glucose + oxygen -> carbon dioxide + water

C6H12O6 + 6O2 -> 6CO2 + 6H2O

Question 12

Anaerobic respiration equation

Answer 12

Glucose-> lactic acid

Question 13

Aerobic vs anaerobic

Answer 13

• aerobic produces more
• aerobic occurs in mitochondria anaerobic occurs in muscles
• anaerobic leads to buildup of lactic acid (cramps) which can be broken down by oxygen (oxygen debt)

Question 14

Fermentation equation

Answer 14

glucose -> ethanol + carbon dioxide

Question 15

Eukaryotic

Answer 15

-complex,large (10-100 micrometers),contain nucleus

Eg.Animal cell, plant cell

Question 16

Prokaryotic

Answer 16

Simple,small (1-10 micrometer),DNA floats in cytoplasm

Eg.bacterial cell

Question 17

Light microscopy

Answer 17

-cheap,easy to use, natural colours sen,resolution up to 2 micrometers,live or dead specimen

Question 18

Electron microscopy

Answer 18

-expensive,difficult to use,black and white images but false colour can be added,up to 0.1nm resolution, only dead specimens

Question 19

Parts of light microscope

Answer 19

Eyepiece lens,objective lens,stage,coarse focus, stage, fine focus, slide, light

Question 20

Cell stains

Answer 20

Methylene blue -> nucleus of anima, cells

-iodine-> nucleus of plant cell

Question 21

Photosynthesis equation

Answer 21

Carbon dioxide + water -> glucose + oxygen

6CO2 + 6H2O -> C6H12O6 + 6O2

Question 22

Starch test (glucose stored as starch)

Answer 22

Iodine will turn from yellow-brown to blue-black if starch present

Question 23

Limiting factors of photosynthesis

Answer 23

1-light intensity
2-carbon dioxide
3-Temperature (until enzymes denature)

Question 24

Inverse square law

Answer 24

Relative light intensity = 1/distance from light source^2

Question 25

Animal cell subcellular structures

Answer 25

Nucleus
Mitochondria (respiration takes place)
Cell membrane
Cytoplasm

Question 26

Plant cell sub cellular structures

Answer 26

Chloroplast (photosynthesis)
Vacuole (keeps cell rigid)
Cytoplasm 
Cell wall
Cell membrane
Nucleus 
Mitochondria