Biological Molecules C2 Flashcards
(140 cards)
1
Q
why can’t oil dissolve in water
A
Oil & other CH molecules are non polar molecules: non polar molecules can’t dissolve in a polar solvent, aka polars don’t mix
2
Q
what is capillary action
A
movement of liquid (by cohesion & adhesion) against force of gravity up a narrow tube
3
Q
ions definition
A
a molecule/atom where no. of electrons isn’t equal to no. of protons
4
Q
what are ions in solution called
A
electrolyte
5
Q
what is - in simple terms - an electrolyte
A
ions in solution
6
Q
why is water a good transport medium
A
solvent & low viscousity
7
Q
why does ice float on water
A
ice has a crystalline structure: more space between molecules = less dense
8
Q
what is hydrogen bonding
A
weak interaction between slightly negatively charged atom with a slightly positively charged one
9
Q
what atoms are attracted in water in hydrogen bonding
A
slightly positive hydrogen atoms are attracted to slightly negative oxygen atoms
10
Q
draw a diagram of hydrogen bonding
A
search it up
11
Q
why does water have a high latent heat of vaporisation
A
high no. of hydrogen bonds aka high intermolecular forces
12
Q
True or False: hydrogen bonds can occur between molecules without a hydrogen atom
A
False, doesn’t have to be a water molecule but MUST have hydrogen atoms with a polar structure
13
Q
True or False: hydrogen bonding only occurs with polar molecules
A
True (if also have hydrogen atoms)
14
Q
difference between cohesion & adhesion
A
cohesion - between water molecules
adhesion - between water & other molecules
15
Q
name 4 monosaccarides
A
fructose, glucose, ribose, galactose
16
Q
name 3 disaccharides
A
sucrose, lactose, maltose
17
Q
name 3 polysaccharides
A
cellulose, starch, glycogen
18
Q
draw out condensation reaction for glucose
A
see book
19
Q
condensation reaction definition
A
reaction where 2 molecules combine to form a large molecule + H2O
20
Q
what does - lysis mean
A
breaking down (a chemical entity)
21
Q
hydrolysis definition
A
splitting a chemical entity with a water molecule
22
Q
what 3 things are carbohydrates used for
A
energy storage, structure, make up other molecules (e.g glycoprotein)
23
Q
name a carbohydrate used for energy
A
glucose
24
Q
name a carbohydrate used for storagr
A
glycogen & starch
25
name a carbohydrate used for structure
cellulose, chitin (in cell wall in prokaryotics)
26
what is the ratio in carbohydrates
Cn(H2O)n
27
why is density at the top of a water drop/ on the water's surface higher?
water molecules at top try to re-configure themselves to be close to other water molecules than the air (due to being polar) causing surface tension.
28
Give some examples of non polar molecules
Glycogen and oils
29
how are monosacharides classified: by their shape or by number of carbons
no. of carbons
30
Name 2 features of monosaccharides
sweet-tasting & soluble in water
31
How are carbons numbered in a chain structure?
From top to bottom
32
How are carbons numbered in a ring structure?
count carbons clockwise starting from far right
33
what is the cytosol?
the aqueous component of the cytoplasm of a cell, within which various organelles and particles are suspended.
34
why is glucose being dissolvable useful in animals/ humans?
can be present in cytosol in the cell, hence used for chemical/metabolic reactions
35
what is the word for this definition: compounds with the same molecular formula (same type & number of atoms) but a different structural formula, (aka in a different shape due to different connections)
structural isomer
36
name 3 hexose monosaccarides
alpha glucose, beta glucose, galactose
37
name 2 pentose monosaccharides
fructose, ribose
38
name a triose monosaccharide (has 3 carbon atoms)
glyceraldehyde
39
what is the structural difference between an alpha and beta glucose molecule?
alpha: hydroxyl group on Carbon1 is facing downwards (vice versa for beta)
40
what is the difference between a hexose and a pentose monosaccharide
hexose: 6 carbons
pentose: 5 carbons
41
draw a ribose monosaccaride?
see book
42
draw an alpha glucose?
see bpok
43
draw a beta glucose?
see book
44
true or false in some monosacchraaide diagrams all the ememnets aren't dorwn on the diagram? which ones?
true, hydrogen and carbon
45
what does an alpha glucose + alpha glucose make?
maltose
46
glucose + fructose
sucrose
47
glucose + galactose
lactose
48
lactose made from
glucose + galactose
49
sucrose made from
glucose+ fructose
50
maltose
alpha glucose + alpha glucose
51
WHat are the products of a alpha glucose + alpha glucose condensation reaction?
maltose+ H2O
52
what is the bond between disaccarides after a condensation reaction called
glycosydic bonds
53
how are glycosidic bonds named
by the carbons numbers attached to them. e.g in alpha glucose + alpha glucose its: 1,4 glycosidiic bond
54
what elements are lipids made from
carbon, hydrogen, oxygen
55
what elements are proteins made from
carbon hydrogen, oxygen, nitrogen, sulfur
56
what elements are nucleic acids made from
carbon, hydrogen, oxygen, nitrogen, phosphorus
57
what are magnesium ions used for in plants
making chlorophyll
58
ignore
j
59
where is fructose naturally found?
fruit
60
where is sucrose naturally found?
sugar cane
61
where is ribose found?
RNA nucleotides
62
Why is glucose hydrophilic
Because it is polar: has a hyfrogen bond between water molecules with its slightly positive hydrogen from the OH group with the slightly negative oxygen from the water
63
What are reducing sugars
Sugars that can donate electrons to another molecule
64
What are non-reducing sugars
Sugars that can’t donate electrons because no available reducing groups
65
What element does Benedicts solution contain
Copper (Cu+)
66
Examples of non reducing sugars
Sucrose
67
How to test for non reducing sugars (before doing reducing sugars steps)?
Add hydrochloride acid
Boil in water bath
Neutralise solution by adding sodium hydrogencarbonate
68
What does hydrochloride acid do in no reducing sugars test?
Hydrolysed (aka breaks) glycosidic bonds , creating monosaccharides
69
What can’t function in acidic conditions reducing sugars or benedicts solution?
Benedicts solution
70
How does Benedicts copper ions show reducing sugars are present?
Cu2+ ions gain an electron = Cu+
71
explain how a hydrogen bond forms?
atoms share electrons unequally, when they bond oxygen has a greater share of electrons than hydrogen = slightly positive & negeative atoms
72
name all the parts of the chain between cellulose chains & cell wall
cellulose chains ---> microfibril ---> macrofibrils --> cellulose fibre ---> cell wall
73
how often does a amylopectin get a 1,6 gylcosidic bond?
after 25-30 alpha glucose'
74
what charge are cations
postively charged ions
75
what charge are anions
negative ly charges ( 2 n's = negative)
76
what are macrofibrils & what do they do?
made of microfibres, macrofibrils connect cellulose chains in all directions for extra strength.
77
True or false: cell wall is permeable, why?
true, macrofibrils have gaps between them allowing water and mineral ions to pass through
78
Microfilaments diameter
3-6nm
79
Microtubles diameter
25nm
80
Microfilaments function
Cell contraction during cytokinesis
| And cell movement
81
Microtubles is made of what protein
Globular tubulin
82
How do you show ribose is a 3D molecule when drawing its structure?
Make the bottom 3 lines of the ring bold
83
How does a bieuret test for proteins work? And mention the positive result
Peptide bonds form lilac compaoinds with copper ions in Bieruet. If positive then blue—-> lilac
84
what does specific heat capacity in water show?
water has high SHC hence does not heat/cool easily = maintain body temperature & good for aquatic animals``
85
what does specific latent heat show?
water as a cooling agent e,g sweating, due to high amounts of energy needed to heat it
86
what organism are each of these stored in: amylopectin, amylose, glycogen
plants: (starch grains) amylopectin, amylose
animals: glycogen
87
which organelle do plants store starch in?
in membrane-bound starch grains and chloroplasts
88
give 3 properties of energy storage polysaccahrideds
- compact
- don't disrupt water potential (like glucose)
- large molecules
89
what makes a cell wall permeable
spaces between MICROfibrils allow water and mineral ions to pass through
90
describe everything you know about unsaturated fatty acids
- has more than 1 double-bonded carbon 1
- this gives it a kink
- the kink pushes the molecule apart = more fluid
91
what happens to the boiling point if there are more unsaturated fatty acids
lowers melting point due to it being more fluid
92
what is the bond between fatty acids and a single glyceride in a triglyceride
ester bond
93
what is the composition of a phospholipid
2 fatty acids, 1 glyceride, 1 phosphate group
94
name 4 things trigylcerides do/ are good for?
- long term energy storage
- insulation
- buoyancy (less dense than water)
- protection -
95
expand on roles of trigycderide: protection
water-proof = protects insects & leaves
| cushioning to protect organs
96
expand on roles of trigycderide: insulation
redce heat loss
| lipids in nerve cells act as electrical insulator
97
what is the text for lipids called
emulsion test
98
whwere is cholesterol made in animals
liver
99
what type of lipid is cholesterol
steroid
100
what is cholesterol made out of
4 carbon-based rings, NOT glycerol or fatty acids
101
example of a quaternary protein (3)
hemoglobin
enzymes
insulin
102
fibrous protein definition
has a re;lativley long, thin structure (1) often having a structural role within an organism
103
globular proteins
has molecules of a relatively spherical shape have metabolic role within an organism
104
which of these are soluble in water: globular proteins or fibrous proteins
globular: soluble
fibrous: insoluble
105
what is a prosthetic group
a non-protein component that is a permanent part of the protein
106
examples of fibrous proteins (3)
collagen & keratin & elastin
107
where is collagen found in animals
artery walls & tendons
108
what is the function of collagen
to give mechnaical strength
109
what is the function of keratin
mechanical protection & provides an impermeable barrier to infections.
110
where is keratin found
nails, hair, hoofs, scales, fur & feathers
111
elastin function
allows living things to stretch and/or adapt their shape
112
where is elastin found?
skin, lungs, blood vessels
113
what is the structure of hemoglobin
2 alpha helix and 2 beta pleasted sheets
114
give an example of a prosthetic group
haem in haemoglobin
115
insulin structure
1 alpha-helix and 1 beta-pleated sheet (1), folds into a tertiary structure joined by disulphide links (2)
116
what us bieuret solution made out of
sodium hydroxide and copper (II) sulphate
117
If amino acids were mixed with biuret solution, will a positive or negative result be shown? why?
biuret tests for peptide bonds specifically, so it's a negative test result
118
what group are fatty acids are a part of?
carboxylic acids + hydrogencarbon chain +hydroxyl
119
what are fatty acids comprised of
carboxyl (-COOH) + hydrogencarbon chain +hydroxyl (OH)
120
what is esterification
a type of condensation reaction between glycerol & 3 fatty acids to make a triglyceride
121
what is the product of esterification
water + triglycerides
122
is oil a unsaturated or staurated lipid
unsaturated trigylecerides
123
lipids defnition
group of susbtances that are soluble in alcohol, but insoluble in water
124
what is glycerol
an alcohol
125
glycerol structure
3 carbons connectd to a OH group each, with rest of bonds with hydrogen atoms, no double bonds
126
why are fatty acids, called an acid
can produce free H+ ions from -COOH group when ionised
127
what is the composition of fatty acids
hydrocarbon chain + carboxyl group with 1 double bond
128
what does a kink in a molecule do
push the molecule apart = more fluid
129
true or false respiration can occur using a lipid as a reactant
true- tryglycsierdes are energy stores
130
cholesterol definition
a sterroid alchohol
131
insulin role
binds to glycoproteins on cell surfaces in liver and muscles to convert glucose to glycogen
132
why is pepsin so stable in stomach's acidiccondtiion
has many acidic R-groups attached to amino acids, hence not many groups bond to H+ = stable
133
why is high water tension important in plants
slows water loss due to transpiration
134
what are microfibrils
H-bonds crosslink bnetween chains in cellulose
135
Name a non reducing sugar
Sucrose
136
Name a reducing sugar
All monosaccharides
137
Cholesterol structure
4 carbon rings with a hydroxyl at one end
138
What is the membrane of a vacuole called
Tonoplast membrane
139
haemolysis definition
The bursting of a animals red blood cell due to water uptake
140
why is ATP known as universal currency
It is present in all cells (1); it is present in all organisms (1). It releases energy in, small/ manageable
quantities
