B2.2 + 3 Tissues, organs, organ systems and Photosynthesis

Question 1

What is a tissue?

Answer 1

A group of similar cells working together to perform a particular function

Question 2

Name 3 types of tissue in mammals and their purposes.

Answer 2

• Muscular tissue which contracts to move whatever it is attached to.
• Glandular tissue which makes and secretes chemicals e.g enzymes and hormones
• Epithelial tissue which covers parts of the body

Question 3

What is the purpose of muscular tissue in the stomach?

Answer 3

Moves the stomach wall to churn up the food

Question 4

What is the purpose of glandular tissue in the stomach?

Answer 4

Makes and secretes digestive juices and enzymes to digest the food

Question 5

What is the purpose of epithelial tissue in the stomach?

Answer 5

Covers the outside + inside wall of the stomach, stops it digesting itself

Question 6

What is digestion?

Answer 6

The breaking down of large insoluble molecules to smaller soluble ones to be absorbed in the bloodstream

Question 7

What is an organ?

Answer 7

A group of different tissues working together to perform a particular function.

Question 8

What happens in the mouth with digestion?

Answer 8

• Food is cut into smaller pieces with teeth (larger surface area for enzymes to work on)
• Amylase acid is produced here by salivary glands and begins to break down carbohydrates into glucose

Question 9

Where is bile produced?

Answer 9

Livers

Question 10

Where is bile stored?

Answer 10

Gall bladder

Question 11

What are the two purposes of bile?

Answer 11

• To emulsify fat for a bigger surface area for lipase to work on
• To neutralise stomach acid so enzymes can work in the small intestine

Question 12

What happens in the small intestine with digestion?

Answer 12

• Finishing breaking down insoluble molecules to soluble molecules
• Lipase enzymes break down lipids and amylase breaks starch down
• All diffuses into the blood

Question 13

What is happens in the oesophagus?

Answer 13

Muscles push down food into the stomach

Question 14

What happens in the stomach with digestion?

Answer 14

• Pepsin breaks protein down

Question 15

What are the two purposes of stomach acid?

Answer 15

• To protect against bacteria

- To create the right PH for pepsin

Question 16

What is the purpose of the pancreas?

Answer 16

To produce enzymes for the small intestine (e.g insulin, lipase, amylase)

Question 17

What happens in the large intestine with digestion?

Answer 17

Excess water is absorbed and faeces are created

Question 18

What is an organ system?

Answer 18

A group of similar organs working together to perform a particular function.

Question 19

What are the function of glands in digestive system?

Answer 19

They produce digestive juices and enzymes

Question 20

What are the main organs of a plant? (3)

Answer 20

• Stems
• Roots
• Leaves

Question 21

What are the main tissues of a plant and their functions? (3)

Answer 21

• Epidermal tissue - covers the plant
• Xylem and phloem tissue - transport water, mineral ions and sucrose around the plant
• Mesophyll tissue - where photosynthesis in a plant occurs

Question 22

What is the equation for photosynthesis?

Answer 22

carbon dioxide + water –light energy–> glucose + oxygen

Question 23

Where does carbon dioxide come from in the plant?

Answer 23

Diffuses into the leaf through the stomata

Question 24

Where does water come from in a plant?

Answer 24

From root hair cells, travelling up the xylem.

Question 25

What is the role of chlorophyll in photosynthesis?

Answer 25

To absorb sunlight and use the energy to convert carbon dioxide and water into glucose.

Question 26

What happens to the oxygen produced by photosynthesis?

Answer 26

It leaves the plant as a waste gas

Question 27

Name 3 limiting factors for photosynthesis.

Answer 27

- Temperature - Carbon dioxide - Light intensity

Question 28

How does increasing light intensity/carbon dioxide affect the rate of photosynthesis?

Answer 28

- As they increase, so does the rate of photosynthesis because light is a limiting factor. - At a certain temperature, a constant rate is reached as the other two factors become limiting factors.

Question 29

How does increasing temperature affect the rate of photosynthesis?

Answer 29

- As temperature increases at first so does the rate of photosynthesis as more energy means more collisions between the particles meaning more reactions. - After the optimum temperature is reached (45 degrees c) increasing temperature becomes a limiting factor as it denatures the enzymes by changing their active site, so the rate of photosynthesis goes down.

Question 30

- Name 5 uses of glucose in plants

Answer 30

- Respiration - Making cell walls - Storage as starch - Storage as seeds - Protein synthesis

Question 31

How is glucose used for respiration?

Answer 31

- Energy is released enabling them to convert the rest of the glucose into other useful substances. - Energy is also used to gather minerals from the soil (ATP for active transport)

Question 32

How is glucose used for protein synthesis?

Answer 32

Plants combine glucose and nitrate ions to make amino acids which are then made into proteins

Question 33

How is glucose used for storage as starch?

Answer 33

- Plants convert glucose into starch for storage as starch is insoluble. Glucose is soluble and would draw lots of water into plant cells making them swell up. - Some plants store them in bulbs/tubers - Potato and parsnip plants store starch underground over the winter so new plants can grow from it in the spring.

Question 34

How is glucose used for storage as seeds?

Answer 34

- Glucose is turned into lipids for storing in seeds and we can get cooking oil from them (e.g sunflower oil)

Question 35

How is glucose used for making cell walls?

Answer 35

Glucose is converted into cellulose for making strong cell walls

Question 36

How do farmers create ideal conditions for farming in greenhouses?

Answer 36

- Greenhouses trap some of the earth's heat, in winter a farmer might use a heater as well. - In summer, ventilation and shades can be used to cool things down. - Supplying light artificially so more photosynthesis takes place - Carbon dioxide levels are increased (e.g using a paraffin heater) - Adding fertilisers to provide all the minerals needed for a healthy growth - Keeping them enclosed makes it easier to keep them free from pests and disease

Question 37

What are nitrate ions used for in plants?

Answer 37

Building proteins and growth

Question 38

What are magnesium ions used for in plants?

Answer 38

Photosynthesis - chlorophyll contains it

Question 39

What are potassium ions used for in plants?

Answer 39

Respiration and photosynthesis

Question 40

What are phosphate ions used for in plants?

Answer 40

Respiration and growth

Question 41

How does the digestive system exchange materials with the environment?

Answer 41

By taking in nutrients and releasing substances (e.g bile)

Question 42

What is the purpose of organ systems in large multicellular organisms?

Answer 42

To transport and exchange materials

Question 43

What 3 environmental conditions affect photosynthesis?

Answer 43

- Time of day - Season - Weather