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Question 1

Name the sub-cellular structures in animal cells

Answer 1

• Cell membrane
• Cytoplasm
• Nucleus
• Ribosomes
• Mitochondria

Question 2

Name the sub-cellular structures in plant cells

Answer 2

• Cell wall
• Cell membrane
• Cytoplasm
• Nucleus
• Ribosomes
• Mitochondria
• Vacuole
• Chloroplasts

Question 3

Name the sub-cellular structures in bacteria cells

Answer 3

• Cell membrane
• Ribosomes
• Cytoplasm
• Chromosomal DNA
• Plasmid DNA
• Flagella

Question 4

What type of cell are plant and animal cells

Answer 4

Eukaryotic

Question 5

What type of cell are bacteria cells

Answer 5

Prokaryotic

Question 6

What is the function of the cytoplasm

Answer 6

• Where chemical reactions take place
• Site of anaerobic respiration

Question 7

What is the function of the nucleus

Answer 7

• Contains all of the cells genetic information

Question 8

What is the function of mitochondria

Answer 8

• Site of aerobic respiration

Question 9

What is the function of ribosomes

Answer 9

• Protein synthesis

Question 10

What is the function of the cell wall

Answer 10

• Maintains cell structure
• Made of cellulose
• Keeps cell rigid

Question 11

What is the function of the cell membrane

Answer 11

• Controls what enters and leaves the cell

Question 12

What is the function of chloroplasts

Answer 12

• Absorb sunlight
• Site of photosynthesis

Question 13

What is the function of the vacuole

Answer 13

• Helps maintain cell structure
• Holds cell sap

Question 14

What is the function of chromosomal DNA

Answer 14

• Holds bacteria’s necessary genes for survival and reproduction

Question 15

What is the function of plasmid DNA

Answer 15

• Holds bacteria’s extra genes e.g. antibiotic resistance

Question 16

What is the function of the flagella

Answer 16

• Helps propel bacteria
• Helps bacteria move

Question 17

Define enzymes

Answer 17

• Biological catalysts that help speed up a reaction without getting used up

Question 18

Why are enzymes imprtant

Answer 18

• Help reduce the need for high temperatures to speed up reaction
• Less likely to cause damage to cells
• Requires less energy
• Very specific

Question 19

What are enzymes

Answer 19

Large proteins

Question 20

What are the two things enzymes do

Answer 20

• Break down one large substrate into tiny products
• Join together lots of tiny substrates into one big product

Question 21

What is the key feature of the active site

Answer 21

It is complementary to the substrate

Question 22

What is the difference between the ‘Lock and key’ theory and the ‘Induced fit’ theory

Answer 22

• Lock and key depicts that the substrate fits perfectly into the active site
• Induced fit states that the active site will change shape to perfectly fit substrate

Question 23

What is the optimum pH for body enzymes

Answer 23

7

Question 24

What types of enzymes have a different optimum pH

Answer 24

Stomach enzymes

Question 25

What is the optimum temperature for body enzymes

Answer 25

37 degrees

Question 26

What is the purpose of digestive enzymes

Answer 26

To break down larger food molecules into smaller more soluble ones that can be absorbed through the small intestine

Question 27

Function and location of amylase

Answer 27

- Breaks down starch into sugars e.g. maltose - Small intestine - Pancreas - Salivary glands

Question 28

Function and location of protease

Answer 28

- Breaks down proteins into amino acids - Pancreas - Small intestine - Stomach

Question 29

Function and location of lipase

Answer 29

- Breaks down fats into glycerol and fatty acids - Pancreas - Small intestine

Question 30

What are specialised cells

Answer 30

- Cells that have differentiated to adapt to a certain function

Question 31

Function and adaptations of a sperm cell

Answer 31

- Deliver genetic material to an egg cell to fertilise it - Fertilisation and reproduction - Has 23 chromosomes in its (haploid) nucleus - **Flagellum** allows sperm cell to swim through uterus - Lots of **mitochondria** to provide energy for swimming - **Streamlined** shape - **Acrosome** contains digestive enzymes which help break down eggs jelly coat

Question 32

Function and adaptations of an egg cell

Answer 32

- Fertilisation and reproduction - Has 23 chromosomes in its (haploid) nucleus - Cytoplasm contains necessary nutrients for embryo growth - **Jelly coat** hardens to prevent more than one sperm cell entering

Question 33

Function and adaptations of a ciliated epithelial cell

Answer 33

- Line surface of organs to help move substances e.g. mucus in one direction - Cilia on their surfaces

Question 34

Describe the food test for reducing sugars

Answer 34

- Benedict's test - 5ml of food sample mixed with 10 drops of benedict's solution (blue) - Place test tube in water bath at 75 degrees - If reducing sugars are present, precipitate will turn green, yellow or brick-red depending on concentration

Question 35

Describe the food test for proteins

Answer 35

- Biuret test - Prepare 2ml of food sample then add potassium hydroxide (to make it alkaline) - Then add copper sulphate - If solution turns pink/purple protein is present

Question 36

Describe the food test for lipids

Answer 36

- Ethanol emulsion test - Prepare 5ml of unfiltered food sample - Add 2ml of ethanol and vigorously shake - Add 2ml of distilled water - If it turns cloudy lipids are present

Question 37

Describe the food test for starch

Answer 37

- Iodine test - Prepare 5ml of food sample - Add iodine - If it turns blue black, starch is present