Chapter 2- Biochemistry- chemical elements and water Flashcards

0
Q

Most frequent element- carbon, what it its percentage?

A

19%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What are the 4 most frequently occurring chemical elements?

A

Carbon
Hydrogen
Oxygen
Nitrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Most frequent chemical, hydrogen, what is its percentage?

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Most frequent chemical, oxygen, what is its percentage?

A

65%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Most frequent chemical, nitrogen, what’s its percentage?

A

3%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 5 other main elements needed by living organisms?

A
Sulphur
Calcium
Phosphorus 
Iron
Sodium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where is sulphur (0.25%) found and what does this allow?

A

Found in certain amino acids (cysteine and methionine) - allowing for proteins to form disulphides bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where is calcium (1.5%) found and what’s its involved with ?

A

Found in bones and teeth and involved in neurotransmitter release in synapses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is phosphorus (1%) a component of?

A

Nucleic acids and cell membranes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is iron (0.7%) found and what’s its purpose?

A

Found in haemoglobin (red protein responsible for transporting oxygen) and allows oxygen transport.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is sodium (0.15%) involved in the generation of?

A

Generation of nerve impulses in neurones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is chemical polarity?

A

Describes how equally bonding electrons are shared between atoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is cell polarity?

A

Differences in shape, structure and functions of cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does oxygen atoms have more of?

A

More protons (+ve)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If oxygen has more protons what does it attract more of and what does this equal too?

A

Attracts more electrons (-ve) which equals it to become slightly negative while hydrogen becomes slightly positive.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Covalent bonded molecules that have slightly potential charge are what?

A

Polar

16
Q

Slightly charged regions of water can attract other polar or charged compounds therefore water molecules can associate with what?

A

Weak hydrogen bonds

17
Q

What are the 3 thermal properties of water?

A

High specific heat capacity
High heat of vaporisation
High heat of fusion

18
Q

What does specific heat capacity measure?

A

Measure of energy required to raise the temp of 1g of substance by 1•C

19
Q

What does heat of vaporisation measure?

A

amount of energy absorbed per gram as it changes from a liquid to a gas/vapour

20
Q

What does heat of fusion measure?

A

amount of energy required to be lost to change 1g of solid at 0•C

21
Q

Why do all these thermal properties of water occur?

A

Result of extensive hydrogen bonding between water molecules

Allows water to absorb considerable amounts of energy with little change ( hydrogen bonds need to be broken first)

22
Q

Is water strongly cohesive (stick to one another)? If so what do they stick too?

A

Yes- tend to stick to other molecules that are charged or polar (adhesion)

23
Q

Why is water strongly cohesive (stick to one another)?

A

Result of polarity of a water molecule and its ability to form hydrogen bonds with appropriate molecules.

24
Q

What are waters solvent properties?

A

Can dissolve organic and inorganic substances that contain electronegative atoms (fluorine,oxygen and nitrogen)

25
Q

Why does water have the solvent properties it does and what does it result in?

A

Polar attraction of large quantities of water can sufficiently weaken intramolecular forces (such as ionic bonds) and result in the dissociation (split into smaller particles) of the atoms.

26
Q

What are the 2 other properties water has?

A

Is transparent- allowing light to pass through it

Expands when frozen become less dense

27
Q

What is a coolant?

A

A liquid or a gas which is used to remove hear from something

28
Q

What do animals and plants do

to facilitate cooling?

A

Evaporation of water from surface of bodies

29
Q

How do animals and plants facilitate cooling?

A

Animals- sweating and panting

Plants- transpiration from leaves in plants

30
Q

Water is a medium for what?

A

Metabolic reactions.

31
Q

What can water do to facilitate chemical reactions in metabolic reactions?

A

Dissolve many inorganic and organic substances

32
Q

What can water absorb in a metabolic reaction?

A

Thermal energy released as a by product of chemical reactions.

33
Q

Is Water is a transport medium?

A

Yes

34
Q

How is water transported up xylem of plant?

A

Forces of attraction between water molecules help facilitate

35
Q

How is water effectively transported for dissolved substances in plants?

A

In plants minerals from soils and sugars from leaves can be transported in water through xylem.

36
Q

How is water effectively transported in dissolved substances in animals?

A

In animals- water in blood is used to transport oxygen,glucose and urea.

37
Q

How is the surface tension useful in water?

A

Force of attraction between water molecules makes water sufficiently dense for some smaller organisms to move along its surface.