2.2- Biological molocules Flashcards Preview

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Flashcards in 2.2- Biological molocules Deck (75)
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1

What type of bond is water called?

Covalent

2

How is a hydrogen bond formed?

Oxygen molecules pull electrons closer,making it slightly negative. This makes hydrogen atoms slightly positive which forms hydrogen bonds.

3

On diagrams, how should you express charge?

with a delta+ or delta- symbol

4

Why is water so important in the human body? (name 3)

It acts as a medium for chemical reactions
It is a major component for tissues
It maintains body temperature

5

Why is water so important for plants? (name 3)

It is required for photosynthesis
it is used to transport substances such as nutrients
It can act as a habitat for organisms such as algae

6

What is water surface tension?

The property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of the water

7

Why is water surface tension important for organisms?

It allows small organisms to walk on water and lily pads to float.

8

What is special about waters SHC?

It has a very high SHC because of the many hydrogen bonds which require lots of energy to break.
This means water is a liquid at RT instead of a gas

9

Why is waters high SHC important for organisms?

It ensures the body temperature remains largely constant
When we sweat, water absorbs heat before evaporating which helps cool us down and regulates temperature

10

Why does water behave as a solvent?

The hydrogen bonds attract other molecules such as salt which can make water heavily attracted to the other molecule and break it apart/dissolve it

11

Why is it important for organisms that water behaves as a solvent?

it allows substances to be dissolved and transported to different parts of an organism

12

Why is water a dense liquid?

the hydrogen bonds pull the water molocules closer together

13

Why is the density of water important for organism?

Waters density means that many animals can float or swim
organisms can also change their density to float/sink

14

What is another word for water concentration?

Water potential

15

What are carbohydrates?

Organic compounds which compose of carbon, hydrogen and oxygen atoms only

16

Why are carbohydrates essential to organisms?

Because they act as energy sources, energy stores and structural unit

17

What is the general formula for monosaccharides.

CnH2nOn

18

What are isomers?

a compound with the same formula but a different arrangement of atoms

19

What are the 2 isomers that glucose exists in?

Alpha glucose and Beta glucose

20

True or false. Monosaccharide can be joined together to form disaccharides.

true

21

What is a reaction called if water is removed?

condensation reaction

22

What is a reaction called if water and enzymes are added to break apart a bond?

Hydrolysis reaction

23

If 2 monosaccharides are bonded together, what is this bond called?

1-4 glycosidic bond

24

Why is an a1-4 glycosidic bond called this?

it is a bond between the first carbon atom and the 4th carbon atom

25

Why are glycogen and starch suitable energy stores?

they are compact and are found in chains which can be easily snipped off for respiration by hydrolysis reactions

26

Why are branched chains better for releasing lots of energy quickly?

more molecules can be "snipped off" by hydrolysis at once which provides more energy

27

Why are polysaccharides less soluble in water than monosaccharides?

They have a large size and because regions which could hydrogen bond with water are hidden on the inside of the molecule

28

True or False. Amylose and Amylopectin are found in animals

False. Amylose and Amylopectin are found in plants

29

Were are Amylose and Amylopectin stored in the organism?

Dense granules in starch grains in cells

30

What disaccharide is formed when 2 alpha glucose molocules are joined together?

maltose