Chapter 6 - Sources of Food

Question 1

What are the 4 categories of food?

Answer 1

crops , farm animals , dairy products , fish and seafood

Question 2

what is the primary source of food

Answer 2

Plants

Question 3

What is photosynthesis

Answer 3

it is a process where green leafed plants make their own food in the presence of sunlight

Question 4

Where the excess food goes ?

Answer 4

to the roots , leaves and stems of the plants

Question 5

the word equation for photosynthesis

Answer 5

carbon dioxide + water + sunlight + chlorophyll = sugar + oxygen

Question 6

what does the excess sugar change into ?

Answer 6

starch

Question 7

how is starch used for photosynthesis?

Answer 7

starch is used as evidence to show that photosynthesis has occured

Question 8

What Color does the iodine turns when starch is present

Answer 8

iodine turns blue

Question 9

pH of 0-6

Answer 9

acidic

Question 10

pH of 7

Answer 10

neutral

Question 11

pH of 8-14

Answer 11

alkaline

Question 12

what does soil provide for the plants

Answer 12

nutrients

Question 13

what does fertilisers do?

Answer 13

it helps to give nutrients to the soil if the soil does not have enough nutrients and helps to increase crop yield

Question 14

natural fertilisers

Answer 14

natural fertilisers such as compost is not toxic and does not pose a threat to the environment

Question 15

chemical fertilisers

Answer 15

chemical fertilisers are also used to increase crop yield

Question 16

disadvantages of chemical fertilisers

Answer 16

1. water contamination
2. negative impact on aquatic life
3. algae bloom
   these chemicals are toxic and harmful for the environment and if we overuse them there can be negative impacts

Question 17

what is slash and burn

Answer 17

slash and burn is an agricultral method where tress are cut down to clear land to grow crops

Question 18

advantages of slash and burn

Answer 18

1. cheap and fast method
2. the ashes provide nutrients for the soil
3. it reduces the occurence of pests and plant diseases

Question 19

disadvantages of slash and burn

Answer 19

1. haze
2. soil erosion
3. possible spread of fires

Question 20

what are pests

Answer 20

they are animals ( insects / rats ) that feed on the crops and destroy them

Question 21

what are weeds

Answer 21

weeds compete with crops for nutrients. this can decrease crop yield as there is lesser nutrients for the crops

Question 22

what are pesticides

Answer 22

pesticides are used to kill pests. they are sprayed onto the crops but it does not harm the crops.

Question 23

what are herbicides

Answer 23

herbicides are used to kill weeds and prevent them from competing with the crops for nutrients

Question 24

the negative impacts when too much of the chemicals are used

Answer 24

1. soil contamination

2. water contamination

Question 25

what is biological methods

Answer 25

this is where farmers bring in the natural enemies of the pests. this helps to prevent the pests from attacking the crops

Question 26

what are the advantages of using this method ?

( non chemical method )

Answer 26

1. the crops will not be contaminated by the chemicals

2. they are not toxic and they do not harm the environment

Question 27

what are the disadvantages of using this method

biological method

Answer 27

when too many natural enemies are introduced, it can disrupt the food chain

Question 28

why do we need to improve food production

Answer 28

because the global human population is increasing

Question 29

what is one way we can improve food production

Answer 29

improve plant varieties by planting good seedlings. good seedlings can make the crops bigger and better.

Question 30

another way we can improve food production

Answer 30

improve animal varieties like milking cows . good meat , bigger farm animals, chickens to grow better eggs

Question 31

what is aeroponics

Answer 31

it is a method where plants are in a mist of the special nutrients solution but it sprayed onto the roots

Question 32

what is hydroponics

Answer 32

its a method of growing plants in a special nutrient solution

Question 33

what are plant hormones

Answer 33

plant hormones are used to kill weeds and help with the ripening of the plant fruit growth.