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Flashcards in unit 2, topic 1 Deck (27)
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1

what is fibre

the tissue of plants stems, leaves, seeds or roots

2

how do humans use plants

humans use plants for clothing paper and building materials.

3

why are plants critical to the ecosystem

because they produce oxygen that most organisms need to live

4

because industries excess carbon dioxide and pollutants to the atmosphere what do plants use do to prevent this

they use carbon dioxide because they breathe in carbon dioxide and let out oxygen.

5

plants are the basis of most...

food webs

6

what are the three reasons why plants are important

1.they provide shelter for countless animals.
2.plants help clean and filter water and absorb it.
3.the roots of the plants help help soil in place and prevent it from being washed or blown away.

7

How many trees does it take to absorb the carbon dioxide from a car driven for one hour?

it takes four large trees to absorb the excess carbon dioxide put into the atmosphere when a car is driven four one hour,

8

today 75 percent of the world's food supply is based on seven major crops..

1.wheat
2. rice
3.maize (corn.)
4.potatoes
5. barley
6. cassava
7. sorghum.`

9

silk is the most

expensive fibre in the world.

10

what are the three natural fibres we use

cotton, hemp, and flax

11

what are the two manufactured fibres

polyester or nylon

12

what is cotton?

cotton is a natural fibre that has been grown and used by humans for centuries. Cotton fibres come from the plant's seed. The fibres are strong , flexible and gradually spiral that causes the strands to interlock when twisted

13

what is hemp

Hemp is the oldest cultivated plant in the world. Hemp has less negative effect on the environment than other sources of fibre do.

14

what is flax

Flax is a food and fibre crop that is grown in the northern, cooler regions of the world. Flax fibres are taken from the stem of a plant and are two to three times strong as those of cotton. Flax fibre is also used for making linen paper.

15

What does the common silkworm eat?

they eat the leaves of a mulberry tree that provide the stable food of the common silkworm

16

Where does the word “denim” come from?

the word denim came from the French name material, serge de nimes, soon turned into the word "denim" in North America

17

more than________ medicines are made from plants

7000

18

what are some medicines that are made from plants

heart drugs, cancer medicines, antibiotics, and pain medicines

19

plants often give us the __________ for medicines that scientists can then copy in laboratories

"blueprints"

20

what is morphine

a powerful pain medicine is found only in the thick fluid of the opium poppy's seed pot , it cannot be manufactured

21

what is quinine

comes from cinchona trees it is used in prevention odd malaria, a deadly disease carried by certain tropical mosquitoes.

22

Where does softwood come from? Where do hardwoods come from?

Softwood comes from coniferous trees, and hardwood comes from broad-leaved, deciduous trees.

23

what are the different uses for plants

Environment
Food
Fibre
Medicine
Transportation

24

what are some example for plants for food

Apple
oranges
bananas

25

what are some example of plants for fibre

cotton
silk
flax
wool
linen

26

What advantages does hemp have over other fibre plants such as wood and cotton?

Hemp has a less negative effect in the environment than other sources of fibre do.

27

Name two ways plants are used in transportation.

Rubber- is made out of latex, that is hard and flexible so it can be a very good tool for transportation

Wood- wood is one way of transportation because it is used for boats, and many people use boats to travel.