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Question 1

What does eukaryotic mean and give examples?

Answer 1

Cells with a nucleus
.Plants
.animal

Question 2

What does prokaryotic mean and give examples?

Answer 2

Cells without a nucleus

.Bacterial

Question 3

What are the different parts of an animal cell?

Answer 3

• Cell membrane
• Cytoplasm
• Nucleus
• Mitochondria
• Ribosomes

Question 4

What are the parts of a plant cell that you don’t find in an animal cell?

Answer 4

• Cell Wall
• Vacuole
• Chloroplast

Question 5

What is the function of mitochondria?

Answer 5

Aerobic respiration occurs and ATP is produced.

Question 6

What is the function of ribosomes?

Answer 6

Protein is made and protein synthesis occurs.

Question 7

What is the function of the nucleus?

Answer 7

Controls the cell and contains DNA.

Question 8

What is the function of the cell wall?

Answer 8

Made from cellulose and provides strength to the cell and supports it.

Question 9

What is the function of chloroplasts?

Answer 9

Photosynthesis occurs providing food for the plant, contains chlorophyll pigment which harvests light for photosynthesis, also makes the plant green.

Question 10

What is the function of a permanent vacuole?

Answer 10

Contains cell sap and improves cell rigidity.

Question 11

Describe the parts of a bacteria cell.

Answer 11

• Cytoplasm
• Cell Membrane
• Cell Wall
• Chromosomal DNA
• Flagella
• Plasmids

Question 12

What is the function of Plasmids?

Answer 12

Small rings of DNA, that code for extra genes to those provided by chromosomal DNA.

Question 13

Where do you find DNA in bacterial cells?

Answer 13

Circular chromosomal DNA floats in the cytoplasm.

Question 14

What are features of a sperm cell?

Answer 14

• Streamlined Shape
• Nucleus
• Acrosome(contains enzymes that break down egg coat, allowing it to burrow inside it)
• Large number of mitochondria
• Flagellum

Question 15

What are the features of an egg cell?

Answer 15

-Cell membrane can change shape to stop other sperm cells from entering.
-Cytoplasm contains nutrients to supply the embryo
-Haploid nucleus
-Jelly coat protects the
egg cell.

Question 16

What are the features of a Ciliated Epithelial Cell?

Answer 16

• Cilia on top of the surface of the cell, it moves substances in one direction along the surface of the tissue.
• It helps move mucus and trapped air particles so it can reach he lungs.
• Also is found in oviduct lining cells, the cilia covers the cell membrane and contain strands of a substance that can contract and cause wavy movement which means in the can safely transport egg cell towards the nucleus.

Question 17

What is the difference of a haploid and diploid?

Answer 17

Haploid has half the set of chromosomes whilst diploid has the full amount.

Question 18

What is the equation for Microscopes?

Answer 18

I/A*M
Image Size= Actual Size * Magnification
Actual Size= Image Size/Magnification
Magnification=Image Size/Actual Size

Question 19

Convert 0.5mm to micrometres.

Answer 19

0.5*100=5000

Question 20

A red blood cell is 8 µm in diameter. How big will its diameter be if magnified ×2000?

Answer 20

8*2000=16000

Question 21

What is an enzyme?

Answer 21

A biological catalyst made up of proteins that speeds up a reaction that makes or breaks a substance without ever being used up itself.

Question 22

Explain how the lock and key model links to the active site of an enzyme?

Answer 22

The active site is designed to only allow in the substrate that fits it specifically, otherwise it won’t work.

Question 23

How do you work out rate of reaction?

Answer 23

1/time in seconds

Question 24

What factors can affect rate of reaction of an enzyme?

Answer 24

• pH
• Temperature
• Concentration of enzyme

Question 25

How can an increase of heat affect how an enzyme functions?

Answer 25

As the heat increases, the rate of a reaction usually increases but after an enzyme has reached its optimum temperature it will then begin to denature as the bonds holding the enzyme together break apart causing the active site to change shape so it can't fit with a substrate and function.

Question 26

Rate of Reaction for an enzyme is...

Answer 26

Amount of substrate used or amount of product formed/ time taken

Question 27

How can a change in pH affect the how an enzyme functions?

Answer 27

If the pH is too high or low, the forces that hold the amino acid chains that make up the protein will be affected, this changes the shape of the active site so the substrate can no longer fit in.

Question 28

What are the different types of enzymes?

Answer 28

protease-breaks down proteins(found in stomach) (pH 2/3) lipase-breaks down lipids(pH7) carbohydrase-breaks down carbohydrates(pH6/7) amylase-breaks down starch, found in saliva in the mouth (pH6/7)

Question 29

Explain the Iodine test for starch.

Answer 29

Start- yellow/orange | End- blue/black if contains starch

Question 30

Explain the Benedicts test for reducing sugars.

Answer 30

``` Start-blue End-blue( no sugar) green (some) orange(lot) reds( a very large amount) ```

Question 31

Explain the Buiret test for protein.

Answer 31

no protein-blue | protein-purple

Question 32

Explain the Ethanol test for lipids (fats and oils)

Answer 32

start- clear, transparent solution | end- (If lipids are present)clear with a cloudy white suspension on top ( the precipitate)

Question 33

What is Calorimetry?

Answer 33

A way to measure the energy taken in and given out during a chemical reaction. This measures calories in food.

Question 34

What would you do to measure calorimetry in food?

Answer 34

1) Take the temperature of 50ml cold water 2) Place the test tube at 45 degrees and hold a burning food sample beneath it 3) When the food is burned up, record the final temperature of the water

Question 35

What is the equation for energy released from food per gram (J)?

Answer 35

mass of water(g) *temp rise*4.2/ mass of food sample (g)

Question 36

A student burned 0.2g of popcorn and 0.5g of bread separately under 20cm3 of water. During the experiment, the temperature of the water increased by 28.6oC when the popcorn was burnt and 38.7oC when the bread was burnt. Which food has more energy per unit mass?

Answer 36

1) First you need to find the amount of energy in each type of food? Popcorn Energy= 20*28.6*4.2=2402.4J Bread Energy= 20*38.7*4.2=3250.8J 2) Then convert it into joules per gram Popcorn-2402.4/0.2=12012 J Bread-3250.8/0.5=6501.6 J Therefore the popcorn has more energy per mass

Question 37

What is diffusion?

Answer 37

The movement of particles from high to low concentration, it goes along the concentration gradient, it is a passive way of transport

Question 38

What is Osmosis?

Answer 38

The movement of particles (water) through solution from an area of high to low concentration through a partially permeable membrane, it goes along the concentration gradient, it's a passive way of transport.

Question 39

What is Active Transport?

Answer 39

The movement of particles from a cell membrane from low to high concentration against the concentration gradient which therefore requires energy, the molecule sticks to the transporter protein which then changes shape and carries the molecule across the cell membrane, it's an active way of transport.

Question 40

What is the difference of passive transport and active transport?

Answer 40

Passive-no energy required | Active- energy is required

Question 41

A piece of potato of initial mass 25 g was placed in water. After 15 minutes its final mass was 50 g. Calculate the percentage gain in mass of the potato?

Answer 41

50-25=25/25=1*100=100%

Question 42

Name the process of which mineral salts are absorbed by a root hair cell from the soil?

Answer 42

Active Transport/Endocytosis

Question 43

What is the difference in Endocytosis and Exocytosis?

Answer 43

Endocytosis is the process of capturing a substance or particle from outside the cell by engulfing it with the cell membrane, and bringing it into the cell. Exocytosis describes the process of vesicles fusing with the plasma membrane and releasing their contents to the outside of the cell.

Question 44

What is the difference between a sperm cell and ciliated epithelial cell?

Answer 44

``` Sperm Cell- flagellum acrosome small surface area extra mitochondria Ciliated Epithelial Cell- found in lungs and oviduct lining cells large surface area moves dirt across in wave like functions designed to stop bacteria and dust entering your lungs. ```

Question 45

What are the differences between a light and electron microscope?

Answer 45

``` Light: cheaper lower resolution lower magnification dead or alive organisms simple, quick preparation Electron: expensive high magnification high resolution dead organisms only complex, long preparation ```