Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology unit 1 > 1.1-Biological compounds > Flashcards

1.1-Biological compounds Flashcards

(70 cards)

Start Studying
1
Q

water has a high latent heat of vaporisation

A

due to cohesion a large amount of heat is needed to vaporise water

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

what are globular proteins?

A

-have functions such as enzymes/antibodies/hormones
-compact and folded into 3D spherical molecules
-soluble in water
-haemoglobin (transports oxygen to the body tissue)

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

what is are phospholipids?

A

-a type of lipid
-the phosphate group is polar and therefore soluble in water
-they have a hydrophilic phosphate head and two hydrophobic fatty acid tails

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

what is a triglyceride?

A

-the most common type of lipid
-fats and ails
-insoluble in water (non-polar)
-soluble in other solvents (ethanol/chloroform/ether)
-formed by condensation reactions between glycerol (type of alcohol) and fatty acids (organic molecules with a -COOH group)

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

describe saturated fatty acids

A

-have a double bond between neighbouring Carbon atoms
-do not have the max possible number of H atoms
-melt more easily
-most oils are unsaturated
-1 C=C bonds means it is monunsaturated
-2+ C=C bonds means it’s polyunsaturated

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

what is starch made of?

A

-starch allows plants to store glucose
-made up of ɑ-glucose monomers added one at a time by condensation reactions
-glucose can be easily added or removed (easily hydrolysed to a ɑ-glucose which is soluble and can be transported to wherever energy is needed)
-compact and has no osmotic effect on the cell so doesn’t affect the water potential of the cell

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

compare triglycerides and phospholipids

A

triglycerides:
-3 fatty acid tails
-no phosphate group
-non-polar (completely hydrophobic)
phospholipids:
-2 fatty acid tails (hydrophobic)
-phosphate group (hydrophilic)

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

lipids and nerve transmission

A

-triglycerides form the myelin sheath surrounding the axon of the neuron

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

what are lipoproteins

A

-when food has been absorbed at the small intestine lipids and proteins cobine to make lipoproteins which travel around the body in the blood stream

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

what happens if the diet is high in saturated fats?

A

-low-density lipoproteins (LDL) builds up
-fatty material (atheroma) is deposited in the coronary arteries which restricts the blood flow and therefore restricts oxygen delivery to the heart tissue
-this restricted blood flow can result in angina
-the coronary arteries become completely blocked and a heart attack is caused

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

what is the Buiret Test?

A

-a chemical test used for detecting the presence of peptide bonds
-in the presence of peptides a copper II ion forms a violet coloured complex in an alkaline solution (Biuret reagent turns blue->violet)
-the intensity of the colour is directly proportional to the protein concentration/number of peptide bonds
-lower protein conc=less obvious colour change

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

what are polysaccharides?

A

-large complex polymers
-formed from very large numbers of identical monosaccharides which are their monomers linked by glycosidic bonds from condensation reactions

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

lipids as thermal insulators

A

-when stored under the skin it acts as a thermal insulator which reduces heat loss

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

what are some properties of water

A

-water is a a dipole molecule as it has an uneven distribution if charge

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

what are disaccharides?

A

-composed of two monosaccharides bonded with a glycosidic bond by a condensation reaction
-two ɑ-glucose molecules form maltose+H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the four levels of a protein structure?

A

-primary
-secondary
-tertiary
-quartenary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

describe the teriary structure of a protein

A

-the secondary structure is folded and twisted to give a more comple and compact 3D structure
-the shape is maintained by disulphide, ionic, covalent hydrophobic and hydrogen bonds
-enzymes have tertiary protein structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

the use of lipids as waterproofing

A

-fats are non polar (insoluble in water)
-leaves have a waxy cuticle to reduce water loss from the leaf surface
-insects also have a waxy cuticle to reduce water loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

cohesion

A

the attraction between water molecules allows water to be transported

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

lipids in cell membrane formation

A

-phosphlipids form a bilayer allowing the transport of non-polar molecules across the cell membrane by simple diffusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is a monosaccharide

A

-the basic unit of a carbohydrate (building blocks to other bigger carbohydrates)
-monosaccharides are sweet and soluble.
-have the general formula (CH2O)n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

water as a transport medium

A

blood is largely water and transports many dissolved substances around the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what happens if a diet has a high proportion of unsaturated fats?

A

-the body will make more high-density lipoproteins (HDL)
-carry harmful fats tot he liver for disposal
-the higher the proportion of HDL:LDL in a persons blood the lower the risk of cardiovascular and coronary heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

describe amylose

A

-as polysaccharide of starch
-unbranched
-coiled
-each ɑ-glucose monomer added forms a C1-C4 glycosidic bond with the adjacent glucose molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what are micronutrients?
minerals needed in small concentrations (Copper/Zinc)
26
what are isomers?
-molecules that have the same chemical formula an the same number of atoms but are arranged differently -ɑ-glucose and ß-glucose
27
what are fibrous proteins?
-preform structural functions -consist of polypeptides in parallel chains or sheets with numerous cross linkages to form long fibres (keratin in hair) -insoluble in water -strong and tough -Collagen provides the properties needed in tendons (attach muscle to bones) -a single fiber consists of three identical polypeptide chains twisted together linked together by cross bridges (stable)
28
how do you test for reducing sugars?
-benedicts reagent -heat (80C+) -reducing sugars will reduce copper II sulphate to form copper I sulphate (a red ppt) -Maltose/Lactose
29
compare haemoglobin and collagen
haemoglobin: -globular -4 polypeptide molecules -each polypeptide is different (4 genes needed to code) -associated with non protein groups (haem group) -the highest level of protein structure is quaternary) collagen: -fibrous -3 polypeptide molecules -each polypeptide is identical (1 gene is needed to code) -not associated with non-protein groups -the highest level of protein structure is secondary
30
describe the primary structure of a protein
-the primary structure is the sequence of amino acids in a polypeptide chain -the sequence of amino acids is determined by DNA -the bond between each amino acids is a peptide bond
31
what are proteins made of?
-proteins are polymers made of monomers called amino acids -a chain of amino acids is called a polypeptide
32
how do you test for non-reducing sugars?
-sucrose is a non-reducing sugar because it does not reduce copper II sulphate -it must first be hydrolysed by boiling in dilute hydrochloric acid to form Glucose and Fructose -the acid must be neutralised with dilute sodium hydroxide before testing with Benedicts reagent -a positive result should be observed as glucose and fructose are reducing sugars (red ppt formed)
33
calcium
-Ca^2+ -hardens bones and teeth -constituent of cell walls
34
density of water
water has a max density at 4C -ice is less dense and therefore floats on the surface and insulates the water beneath -reduces the tendency for large bodies of water to freeze completely allowing organisms to survive
35
what formed between two amino acids in a condensation reaction?
-peptide bond -the resulting compound is a dipeptide
36
water has a high specific heat capacity
-large amounts of heat is needed o raise the temperature of water -prevents large fluctuations in water temps, keeping aquatic environments stable
37
lipids as a metabolic water source
-trigylcerides produce a lot of metabolic water when oxidised -essential for desert animals that survive on metabolic water from its fat intake (kangaroo rat/camel)
38
iron
-Fe^2+ -constituent of haemoglobin
39
Nitrate
-NO^3- -used to make nucleotides (DNA/RNA) used in the making of amino acids
40
what are macronutrients?
minerals needed in larger amounts (magnesium and iron)
41
inorganic molecules
molecules that have no more than a carbon atoms
42
what is an essential amino acid?
-amino acids cannot be synthsides by our bodies so must be provided by our diet
43
phosphate
-PO4^3- -used to make nucleotides -constituent of phospholipid -hardens bones
44
water as a solvent
-positive and negative charges attracts other charged particles (glucose) -ions and polar molecules can dissolve in water, non-polar molecules cannot
45
the use of lipids in steroids and cholesterol
-steroids/sex hormones are lipids -have a ring structure rather than a long chain
46
lipids as energy reserve in plants and animals
triglycerides contain more C-H bonds than carbohydrates (yields approx x2 as much energy when oxidised) -fat is stored under the skin and around organs (animals) -triglycerides are stored as oils in seeds (plants
47
describe amylopectin
-polysaccharide of starch -branched -forms C1-C4/C1-C6 glycosidic bonds
48
describe glycogen
-the main storage product in animals -easily hydrolysed to a ɑ-glucose which is soluble and can be transported to wherever energy is needed -has similar structures to amylopectin -ɑ-glucose are joined by C1-C4 and C-C6 glcosidic bonds (similarity) -glycogen has shorter C-C4 glucose chains and there are more C-C6 branch points (difference) -more branched than amylopectin
49
how do you test for fats and oils?
-mix the substance with absolute ethanol any lipids present will dissolve -add an equal volume of water into the sample and shake -any dissolved lipids come out of the solution and form an emulsion (cloudy white)
50
what are the types of monosaccharides?
TRIOSE: important in metabolism. they are intermediates in the reactions of respiration and photosynthesis PENTOSE: constituents of nucleotides (deoxyribose in DNA/ribose in RNA) HEXOSE: Glucose is a source of energy in respiration. C-H and C-C bonds are broken to released energy which is transferred to ATP
51
surface tension
at ordinary temps water has high surface tension -the cohesion of water molecules supports organisms such as pond skaters allowing them to walk on water
52
describe cellulose
-a structural polysaccharide found in plant cell walls -consists of many long and parallel chains of ß-glucose joined by C1-C4 glycosidic bonds -bonds rotate 180° allowing hydrogen bonds to form between OH groups of adjacent cellulose chains -between 60 and 70 cellulose molecules become cross linked to form bundles (microfibrils-bunch together to form fibres) -unreactive and stable (due to it being unbranched) -high tensile strength (due to the formation of microfibrils/fibres)
53
what is non-essential amino acids?
-can be synthesised by our bodies
54
what do phospholipids form?
a phospholipid bilayer which is the basis of all cell membranes
55
what bond is formed in a triglyceride?
an ester bond (O-C=O group) -broken by hydrolysis
56
describe saturated fatty acids
-no double bonds -carry the max possible number of H atoms -solid -animal lipids tend to be saturated
57
give examples of different disaccharides and their biological roles
maltose=>Glucose+glucose (in germinating seeds) sucrose=>glucose +fructose (a product of photosynthesis which is transported in the phloem) Lactose=>Glucose+Galactose (found in mammalian milk)
58
what is the structure of an amino acid?
-it has an amino group (-NH2)-basic/alkaline -it has a carboxyl group (-COOH)-acidic -a hydrogen atom -a variable group (-R)
59
describe the quaternary structure of a protein
-arises from the combination of two or more polypeptide chains in tertiary form -these are associated with non-protein groups and form large complex molecules (haemoglobin-4 polypeptide chains)
60
what is a micelle?
-in water the hydrophobic fatty acid tails turn upwards to avoid the water to form a fatty droplet (micelle)
61
organic molecules
molecules that have a high proportion of carbon and hydrogen atoms
62
how is a glycosidic bond broken?
-hydrolysis -water is chemically added to break a bond between monomers
63
what is the link between saturated fatty acids and heart disease?
-there is a possible link between the consumption of saturated fatty acids and heart disease -the main cause of heart disease is fatty deposits in the coronary arteries (artherosclerosis) and high blood pressure (hypertension) -a diet that is high in saturated fatty acids, smoking, lack of excerise and ageing are all contributory factors
64
the use of lipids as protection
fats are often stored around delicate organs such as kidneys
65
describe the secondary structure of a protein
-the secondary structure is the shape that the polypeptide chain forms due to hydrogen bonds -H bonds twist and fold the polypeptide to form an alpha helix or a beta pleated sheet
66
describe chitin
-similar structure to cellulose -a structural polysaccharide -found in the exoskeleton of arthropods (insects) and fngal cell walls -long chains of ß-glucose linked by C1-C4 glycosidic bonds -each monomer has a group derived from amino acids added (acetylamine group) (difference) -alternate glucose molecules are rotated by 180 to allow H bonds to from between adjacent OH groups of chitin chains -crosslinked parallel chains form microfibrils -strong -waterproof -lightweight
67
describe the structure of the enzyme lysozyme
-tertiary structure -the disulphide bonds connect different parts of the polypeptide molecule together which maintains the shape of the active site allowing enzyme-substrate complexes to form
68
magnesium
-Mg^2+ -constituent of chlorophyll
69
lipids and its low density/bouyancy
-fats have fairly low density -helps animals float -seeds whch store oils can also be dispersed easily as they are light
70
chemical reactions take place in water
transport of ions and polar molecules allows chemical reactions to take place when particles or molecules meet

biology unit 1 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions