Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Biological molecules > Flashcards

Biological molecules Flashcards

2.1.2

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

How do hydrogen bonds form between water molecules ?

A

Water is a polar molecule meaning oxygen is more electronegative than hydrogen which therefore makes oxygen slightly negative and hydrogen slightly postive .
There are intermolecular forces of attaction between a lone pair of oxygen of one molecule and hydrogen on an adjancent molecule

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

State biological important properties of water

A
  • High specfic heat capacity
  • High latent heat of vaporisation
  • High surface tension
  • Reaches maximum density at 4 degrees
  • Cohesion between molecules
  • Incompressible
  • Good solvent
  • Transport medium
  • Medium for chemical reactions
  • Habitat for organisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why is it important that ice is less dense then water?

A

Ice is less dense then water because the hydrogen bonds are held in fixed postions further away.
The ice floats which insulates the water underneath from freezing protecting habitats underneath

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

Why is it important that water has a high surface tension?

A
  • Slows water loss due to transpiration in plants
  • Water rises unusually high in narrow tubes, lowering demand on root pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why is it important that water is a good solvent ?

A

Polar universal solvent dissolves and transports charged particles.
This is because waters charge is unevenly distrubted so it is able to dissolve charged particles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

1.Why is high specific heat capacity important?
2. Why is latent heat of vapourisation important?

A
  1. Acts as a temperature buffer which helps to resist fluctuations in core temperatures to maintain optimum enzyme activity
  2. Colling effect when water evaporates from skin surface as sweat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a:
1. Monomer
2. Polymer

A
  1. Monomers - smaller units that join together to form molecules (monosaccharides, amino acids, nucleotides)
  2. Polymer - molecules formed when many monomers join together (polysaccharides, proteins, DNA / RNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens in a:
1. Condensation reaction
2. Hydrolysis reaction

A
  1. Chemical bond forms between 2 molecules and a molecule of water is produced
  2. A water molecule is used to break a chemical bond between 2 molecules with the help of a enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Carbohydrates + lipds : C,H,O
Proteins : C,H,O,N,S
Nucleic acids : C,H,O,N, P

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

Alpha glucose

Properties of a alpha glucose ( monosaccharides + diasaccharides)
* small + water solube = easily transported in the blood
* sweet
* forms crystals

A

Structure of an alpha glucose
* triose - 3 carbons
* pentose - 5 carbons
* hexose - 6 carbons

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

What is a diaccharides ?

A

Two monosaccharides join to form a diaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. alpha glucose + alpha glucose =?
  2. alpha glucose + fructose =?
  3. alpha glucose + galactose =?
  4. beta glucose + beta glucose =?
A
  1. maltose
  2. sucrose
  3. lactose
  4. cellulose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the properties of polysaccharides?

A
  • Insolube in water
  • Not sweet
  • Cant be crystalisised
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the function of starch ?

A
  • Insolube in water - doesnt affect the water potential ( glucose lowers the water potential)
  • Brached - main energy storage in plants ( branched structure in amylopectin means lots of glucose can be released and used quickly for respiration
  • Compact - doesnt take up of space + good energy storage molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the structure of starch:

A
  1. amylose - **1,4 glycosidic bonds **with a helix and intermolecular H bonds = compact ( alpha glucose) coiled
  2. amylopectin - 1,4 + 1,6 glycosidc bonds , branched to access glucose to be accessed more easily (roots in plants) colied but has branches
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the structure and function of glycogen?

A
  • Function : **main energy storage **of alpha glucose in animal cells (liver +muscles)
  • Structure :** 1,4 + 1,6 glycosidic bonds** , branched,less coiled , compact , more ends at the end of the branches
    insolube in water - doesnt affect water potential
17
Q

What is the function and strucutre of cellulose ?

A
  • Structure: Polymer of beta glucose molecules joined together by hydrogen bonds forming strong fibres called mircofibrils - straight chains
  • Function: high tensile strength because of the glycosidic bonds and hydrogen bonds between the chains preventing bursting when turgid , fibres go in all directions so gives it extre strength
  • ** fully permeable**
  • turgid to help protect the strucure of the whole plant
  • Fibre - Helps maintain a healthy digestive system
18
Q

How is a glycosidic bond formed with two beta glucose?

A

the alternate b glucose is rotated through 180 forming strain chains . Forms hydrogen bonds with adjancent molecules

19
Q

What is the function of :
1. amylose
2. amylopectin
3. glycogen
4. cellulose

A
  1. respiration in plants, store of energy
  2. respiration in plants, store of energy
  3. used to store glucose in the liver + muscles , aerobic respiration
  4. cell wall and fibre
20
Q

How does a triglycerides form?

A

A condensation reaction between 1 molecule of glycerol and **3 fatty acids **with form a ester bonds

21
Q

What is the function of lipids ?

A
  • Energy source
  • structure
  • thermal insulation
  • electrical insulation
  • protection + cushioning
  • waterproofing
  • hormones
22
Q

what are :
1. saturated acids
2. unsaturated fatty acids

A
  1. Saturated
    * all carbon atoms have formed the maximum number of bonds
    * no double bonds = no kinks
    * high melting point = solid at room temp.
  2. unsaturated
    * contain atleast one double bond
    * double bonds = liquid at room temperature
    * monounsaturated - one double bond
    * polyunsaturated- two or more double bond
23
Q

What is the function of triglycerides ?

A
  • energy store
  • release high amounts of energy
  • non-polar so insolube and doesnt affect water potential waterproofing
  • respiration which releases water for desert animals
    * thermal insulation
24
Q

What is the structure of phospholipids ?

A
  • glycerol backbone attached to 2 hydrophobic fatty acid tails and 1 hydrophilic polor phosphate head
25
Q

What is the function of phosolipids?

A
  • Forms phosolipid bilayers - tails inwards , heads outwards
  • Forms micelles - tiny balls with the tails pointing in and heads out
  • water proofing
26
Q

What is the structure and function of cholesterol ?

A

Structure: Steriod structure of 4 hyrdocarbons with a hydrocarbon tail and a hydroxyl group on the other side
Function : adds stability to cell surface phospholipid bilayer by reducing fluidity

27
Q

How do polypeptides form?

A

A condensation reaction between amino acids to form a peptide bond

28
Q

What are the primary structure of a protein?

A
  • primary structure - a specific sequence of amino acids
29
Q

What is the secondary structure of a protein?

A
  • alpha helix - spiral shape and hydrogen bonds parallel to helical axis
  • b- pleated sheets - a flat sheet where the polypeptide that folds back on itself
    stablised by hydrogen bonds
30
Q

W

What is the tertiary structure of proteins ?
What are the bonds present as well ?

A
  • A 3d structure formed by futher folding
  • Disulfide bonds - Strong covalent s-s bonds between molecules of the amino acid cysteine (very strong)
  • Ionic bonds - relatively stron bonds between charded R-groups (quite strong)
  • Hydrogen bonds - numerous and easily broken (very weak)
  • Hydrophobic/hydrophilic interactions - whether the R group faces inwards or outwards away from the water or towards the water ( weak)
  • Peptide Bonds - Stong covalent bonds between amino acids ( very , very strong )
31
Q

What is a conjugated protein?

A

Proteins that contain a non protein part which is known as the prosthetic group which may be attached to any of the bonds

32
Q

Describe the structure of a globular proteins

A
  • Spherical and compact
  • precise primary structure with a non repeating amino acid sequence
  • complex secondary and tertiary structure
  • solube in water
33
Q

What is the function of globular proteins ?

A
  • Hydrophilic R groups face outwards and hydrophobic r groups face inwards = usually water soluble
  • Involved in metabolic processes e.g enzymes , amylase. insulin
34
Q

What is the structure of haemoglobin?

A
  • Globulat conjugated proteins with a prosthetic group ( haem)
  • 2 alpha chains and 2 beta chains
  • Water soluble so dissovles in plasma
  • Fe2+ haem group forms a bond with o2 to transport oxygen around the blood
35
Q

what is the structure of fibrous proteins?

A
  • long narrow fibres
  • simple primary structure with repeating amino acid sequence
  • simple secondary and tertiary structure
  • insolube in water
36
Q

What is the function of :
1. Collagen
2. elastin
3. keratin

A
  1. component of bones, cartilage, connective tissue , tendons
  2. elasticity to connective tissue , arteries , skin , lungs, cartilage and ligaments
  3. structural component of hair , nails , hooves
37
Q
A

Biology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions