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topic two Flashcards

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AP® Biology flashcards Biology 101 flashcards
1
Q

carbon based compounds found in living organisms incoude

A

lipids
carbohydrates
nucleic acids
proteins

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2
Q

how many bodns can carbon form

A

4

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3
Q

waht are macromolecules

A

organic compounds. There are four types of macromolecules: carbohydrates, lipids, proteins and nucleic acids. All of them contain carbon, hydrogen and oxygen atoms.

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4
Q

carbohydrates are comprised of

A

carbon, hydrogen and oxygen. the ratio of hydrogen to oxygen is 2:1

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5
Q

proteins consist of

A

amino acids arranged in long chains

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6
Q

function of alpha d glucose

A

Used in the production of ATP in cells.

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7
Q

function of beta d glucose

A

Used to build cell walls in plants.

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8
Q

function of starch

A

Used as long-term storage in plants.

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9
Q

function of ribose

A

Used as a component of DNA and RNA.

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10
Q

function of triglycerides

A

Used as long-term storage in adipose tissue in animals.

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11
Q

function of steroids

A

Used as chemical messengers in the body, have a distinctive ring shape.

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12
Q

function of phospholipids

A

Major component of plasma membranes.

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13
Q

function of strutural proteins

A

Proteins such as keratin and collagen form the structural framework of many parts of the body.

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14
Q

function of enzymes

A

Metabolic proteins that speed up chemical reactions in the body.

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15
Q

function of polypeptides

A

A sequence of amino acids that may make up a protein, or a series of polypeptides can also make up a protein.

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16
Q

function of dna

A

Used to store genetic information.

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17
Q

function of rna

A

Used to create proteins at ribosomes using the information stored in DNA.

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18
Q

basic structures of glucose, amino acids, fatty acids and ribose.

A
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19
Q

what implies the monomer is an aminoa cid

A

-COOH

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20
Q

what implies the monomer is a fatty acid

A

-COOH attached to a long hydrocarbon chain

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21
Q

what detects starch in food

A

iodine solution. will turn blue black

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22
Q

waht detects protein in food

A

biuret test. the liquid turns purple.

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23
Q

what detects carbs

A

benedict’s solution, reducing sugars. will change from blue to orange or brick red when heated

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24
Q

anabolism

A

is the synthesis of complex molecules from simpler molecules; it is a process that requires the input of energy. Anabolism includes the formation of macromolecules from monomers by condensation reactions.

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25
Q

catabolism

A

the breakdown of complex molecules into simpler molecules and includes the hydrolysis of macromolecules into monomers. The breakdown of sugars (including glycolysis) or fats to release energy are all examples of catabolic reactions. Catabolism is a process during which energy is released.

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26
Q

Hydrolysis reaction

A

the breaking of chemical bonds by the addition of water molecules.

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27
Q

Condensation reaction refers to

A

the reaction in which two smaller organic molecules combine to form a larger molecule with the accompanied formation of water or some other simple molecule.

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28
Q

define metabolism

A

the sum of all the enzymatic reactions in a cell or organism.

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29
Q

define anabolism

A

the synthesis of more complex molecules from simpler precursor molecules.

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30
Q

define catabolism

A

the breakdown of complex molecules into simpler molecules.

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31
Q

urea formula

A

CO(NH2)2

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32
Q

function of urea

A

used by body to excrete nitorgen and is also used as a nitrogen fertiliser

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33
Q

who synthesised urea and when

A

Friedrich Wöhler in 1828

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34
Q

what contradicted the theory of vitalism

A

artifical synthesis of urea

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35
Q

why is water a polar molecule

A

the oxygen atom is more electronegative than the hydrogen atoms. this means that oxyen has a greater pull on the electron cloud, acquiring a slightly negative charge whilst the hydrogens are slightly posiitive.

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36
Q

polarity of warer allows

A

important biological properties such as solvency, cohesion and adhesion.

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37
Q

what allows the formation of hydrogen bonds

A

the partial positive hydrogen atoms of one molecule are attracted to the partial negative oxygen atoms of other water molecules.

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38
Q

why are fats and oil hydrophobic

A

they are non polar

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39
Q

cohesion

A

tendancy of wawter molecules to stick to each other due to the hydrogen bonding between them. Each water molecule can potentially form four hydrogen bonds with other water molecules in a tetrahedral arrangement.

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40
Q

are the cohesive forces in water strong

A

yes, Although hydrogen bonds are weak bonds, the presence of a large number of hydrogen bonds in water gives the cohesive forces great strength.

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41
Q

what causes high surface tension in water

A

strong cohesive forces.

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42
Q

what is responsible for water droplets adopting a spherical shape, minimising the ratio of area to volume.

A

high surface tension

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43
Q

what is adhesion

A

the interaction that water molecules have to other molecules, and is why water molecules stick to other polar compounds

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44
Q

what causes capillary action

A

forces of adhesion

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45
Q

what creates the unique thermal properties of water inc high specific heat capacity

A

the hydrogen bonds

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46
Q

how much energy is required to turn liquid water into water vapour

A

a large amount. this means water is a great cooland and has a high latent heat of vaporisation

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47
Q

can water dissolve ionic compounds

A

yes

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48
Q

benefit of cohesive properties of water to living organisms

A

Allows water to be pulled up from the roots to the leaves of plants.
Permits insects, such as pond skaters, to walk/float on the surface of water to catch their prey.

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49
Q

benefit of adhesive properties of water to living organisms

A

Capillary action generated by adhesive forces assists the pumping action of the heart to help blood move through blood vessels.
Adhesion of water molecules to the cell wall of xylem vessels helps water move against gravity from the roots to the leaves.

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50
Q

benefit of thermal properties of water to living organisms

A

Evaporation of sweat from body surfaces involves heat loss, which brings about a cooling effect.
The high specific heat capacity of water makes aquatic ecosystems more stable than terrestrial.

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51
Q

benefit of solvent properties of water to living organisms

A

Water dissolves mineral ions in the soil and transports it along xylem vessels from the roots to all parts of the plant.
Water in blood plasma dissolves a range of solutes and gases, which makes it possible for blood to transport nutrients and gases around the body
Water’s versatility (its ability to exist as a liquid, solid and vapour) makes water a universal solvent and medium for numerous biochemical reactions.

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52
Q

What causes water to have a relatively high specific heat capacity?

A

Hydrogen bonds between hydrogen and oxygen of different water molecules.

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53
Q

What property of water makes it an excellent coolant?

A

Water molecules are dipolar, allowing strong cohesive forces between the molecules.

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54
Q

is blood oil based or water based

A

water based

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55
Q

list the biological molecules found in blood

A

glucose
amino acids
fats
cholesterol
oxygen
sodium chloride

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56
Q

why does blood gluclsoe level need to be strictly maintatined

A

it effects osmolarity

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57
Q

what changes the solubility of amino acids

A

size and r group

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58
Q

when will amino acids easily dissolve in water

A

if they contain a hydrophilic r group. if hydrophobic hey will be transported in lower concentrations

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59
Q

how are fats transported in blood

A

generally insoluble in water so transported in lipoproteins a

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60
Q

what are lipoproteins

A

a single layer of phospholipids with proteins embedded among the molecules surrounding the fat

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61
Q

how is cholesterol transported in the blood

A

lipoproteins are needed

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62
Q

how ix oygen transported in the blood

A

Oxygen is nonpolar, however, due to its small size it is soluble in water to a limited extent. This is why oxygen transported in the blood is bound to the protein called hemoglobin.

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63
Q

how is sodium chloride transported in the blood

A

as Na+ and Cl- ions

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64
Q

what substances are dissolved in the blood

A

Amino acids, sodium chloride and carbon dioxide.

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65
Q

how is starch transported in theblood

A

broken down into glucose molecules

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66
Q

how is methane produced

A

a gas produced by anerobic bacteria as a waste product. is also a greenhouse gas

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67
Q

physical states of water and methane at 20 degrees

A

liquid and gas

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68
Q

polarity of water and methane

A

polar and non polar

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69
Q

water and methane as a solvent

A

excellent and not

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70
Q

boiling temp of water and methane

A

100 and -161

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71
Q

melting point of water and methane

A

0 and -182

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72
Q

specific heat capacity of water and methane

A

4.2 and 2.2

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73
Q

latent heat of vap of water and methane

A

2257 J/g and 760J/g

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74
Q

what explains the differences in thermal properties of water and methane

A

the presence of hydrogen bonding in water

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75
Q

how can carbs be classified

A

monosaccharides, disaccharides and polysaccharides.

the former two are considered sugars; polar

the latter is a macromolecule resulting from polymerisation or condensation of sugars and is not soluble inw ater

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76
Q

monosaccharides

A

the simplest types of carbohydrates. The number of carbon atoms can be from three to seven. The carbons are joined to a hydroxyl group (-OH).

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77
Q

what happens when monosaccharides link together via a condensaiton reaction

A

they form a glycosiddic bond producing a disaccharide

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78
Q

Condensation reaction refers to the reaction in which

A

two smaller organic molecules combine to form a larger molecule and a molecule of water or some other simple molecule. The reaction opposite to condensation is called hydrolysis. This is a chemical reaction in which water is used to break down the bonds of big compounds.

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79
Q

hydrolysis

A

is when water (‘hydro’) is added and used to break up (‘lyse’) a polymer, a disaccharide or a dipeptide into smaller monomers.

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80
Q

glucose exists in two forms:

A

D glucose and L glucose

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81
Q

differences between the alpha de glucsoe and beta d glucose

A
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82
Q

how do animals and fungi store energy

A

glycogen

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83
Q

how do plant sstore energy

A

starch in their roots and stems

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84
Q

what are chitin exoskeletons mad eup of

A

carbs

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85
Q

what is scurose made up of

A

glucose and fructose

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86
Q

waht is maltose made up of

A

2 glucose units

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87
Q

waht is lactose made up of

A

glucose and galactose

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88
Q

what is starch made from

A

glucose

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89
Q

what is glycogen made up of

A

glucose

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90
Q

what is cellulose made up of

A

glucose

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91
Q

How is maltose formed?

A

By joining two glucose molecules in a condensation reaction.

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92
Q

what polysaccharides make up starch

A

amylose and amylopectin (both of these have glucose as their monomer subunit)

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93
Q

structural difference in starch and cellulose

A

In cellulose molecules, all glucose monomers are oriented in the same direction.

In contrast, starch molecules are made up of glucose monomers that rotate 180 degrees around the backbone chain.

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94
Q

is amylose or amylopectin branched

A

amylopectin

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95
Q

uses of amylopectin

A

gives starch its characteristic stickiness. This is very useful in the food, paper and chemical industries, where it is used to make paste, glue (adhesive) or as a lubricant.
makes up 80% of the starch content in potatoes. A genetically modified potato which predominantly produces amylopectin starches (useful for adhesive making), has been produced and approved for cultivation.

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96
Q

cellulose fucntion

A

sturcutral component in plant cell walls

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97
Q

amylopectin and amylose are

A

two differnet forms of starch.

usually in starch glucose monomers rotate 18p degrees around backbone chain.

the arrangement of glucose molecules can be linear, which is called amylose, or branched, which is called amylopectin

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98
Q

how are triglycerides formed

A

by condensation reactions between one glycerol and three fatty acids, creating ester bonds.

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99
Q

distinguish between fats and oils

A

fats are solid at room temp, oils are liquid

100
Q

difference betwen saturated fatty acid and unsaturated fatty acid

A

A saturated fatty acid has no double bonds between any of the carbon atoms that make up the hydrocarbon chain.

An unsaturated fatty acid can be monounsaturated if it has just one double bond

101
Q

what is a polyunsaturated fatty acid

A

has two or more double bonds in its hydrocarbon chain

102
Q

cis is when

A

both hydrogens on one side

103
Q

trans when

A

hydrogen on either side

104
Q

key features of cis isomers

A

commonly occur in nature
lower melting point

105
Q

key features of trans isomers

A

produced artifically when lipids formed by polyunsaturated fatty acids from plants are ‘partially hydrogenated’ chemically (e.g. when margarine is made from vegetable oil). This process makes plant fatty acids more solid, like saturated fats.

higher melting points

106
Q

phospholipids composition

A

when one fatty acid in a triglyceride is replaced by a phosphate group

107
Q

whya re steroids lipids

A

hydrophobic and insoluble in water

108
Q

why do steroids not resemble lipids

A

they have four fused rings

109
Q

are cis or trans isomers bad

A

trans

110
Q

Which substances are examples of steroids?

A

cholesterol and sex hormones

111
Q

why are lipids better for energy storage

A

higher energy content and can act as thermal insulators

112
Q

a gram of lipid gives

A

twice the amount of energy as a gram of glycogen

113
Q

each gram of glycogen is stored with

A

2 grams of water

114
Q

key properties of lipids

A

more energy per gram
less dnese
non polar but does not affect movement of water
excellent heat insulation
water insoluble

115
Q

The two types of fats that are generally considered to be unhealthy are

A

the trans fats and those rich in saturated fatty acids.

116
Q

Trans fats, on the other hand, are formed by

A

the hydrogenation of vegetable oils by adding hydrogen to unsaturated fats under pressure. This process increases the spreadability of vegetable oils and extends the shelf life of certain food products

117
Q

what is the evidence linking the ocnsuption of trans and saturated fats to the incidence of CHD

A

The hypothesis is that the trans fats and saturated fats contribute to the formation of atherosclerotic plaques in arteries, which in turn lead to heart attack

118
Q

Key questions to consider when doing an evaluation:

A

Is there a correlation between the lipid and the incidence of the disease under investigation?
Has a statistical analysis been carried out to determine the significance of the data collected?
Is the data collected widely spread? The more widely spread the data, the lower their significance and reliability. Standard deviation and error bars can be used to determine the extent to which the data is widely spread.
Was the sample used for the investigation big enough? Small samples do not provide reliable data.
Was the factor measured as the health indicator valid? For instance, how fast a person can run is not a valid way to measure health.
Were representatives of the whole human population considered? Or only a specific age group, gender, ethnicity, lifestyle, etc.?
Were all important variables effectively controlled?
Were realistic dietary levels of lipids considered?

119
Q

bmi is

A

weight / height squared

120
Q

health risk classification acording to bi

A

underweight is under 18.5
normal is 18.5 to 24.9
overweight is 25-29.9

121
Q

how many amino acids are there

A

20

122
Q

how do two amino acids bind in a condensation reaction to form a depeptide

A

The carboxyl group and the amino group provide OH and H, respectively, for the formation of a water molecule.

123
Q

Which chemical reaction is taking place when a dipeptide is converted to two amino acids?

A

hydrolysis

124
Q

Name the bond that forms when two amino acids react together in a condensation reaction.

A

ester bond

125
Q

genes normally code for how many polypeptides

A

one

126
Q

what determines the shape and function of the protein

A

order of rthe amino acids

127
Q

waht determines the types of bonds and itneractions with other molecules aminoa cids can make

A

r groups

128
Q

A single change in the order of amino acids can cause changes in a protein’s conformation, resulting in

A

a change of shape or loss of function

129
Q

. In sickle cell anemia, the glutamic acid is substituted by ???. This causes severe changes to the structure of hemoglobin.

A

valine

130
Q

waht is the primary structure

A

the sequence of amino acids in a protein

131
Q

what is the secondary structure

A

involves the folding of the chains on themselves to form pleated sheets or alpha helixes

132
Q

what is the tertiary structure?

A

When the polypeptide folds and coils to form a complex three-dimensional shape

133
Q

what is the quaternary structure

A

A quaternary structure only occurs in proteins that are made up of two or more polypeptide chains and refers to the way the multiple subunits are held together in a multi-subunit complex.

134
Q

hemoglobin has which chains

A

2 alpha 2 beta

135
Q

proteome meaning

A

each persons unique set of proteins

136
Q

globular proteins

A

They tend to play active roles in the cell’s metabolism. They consist of complex polypeptide chains that can be linked to other chains to form large complex proteins

137
Q

fibrous proteins

A

more like a fibre; long and thread-like. Usually, fibrous proteins are made of long polypeptide chains where the hydrophobic R groups are exposed, making the molecule insoluble. They are often found in structural parts of organisms, such as tendons and skin

138
Q

rubisco

A

globular
An enzyme involved in the fixation of CO 2 in chloroplasts.

139
Q

insulin

A

globular
A hormone produced by the beta cells of the pancreas, which is involved in glucose uptake from the blood.

140
Q

immunoglobin

A

globular
These are large Y-shaped proteins, also called antibodies, involved in fighting infections by specifically recognising and binding to antigen molecules.

141
Q

rhodopsin

A

globular

A protein linked to pigment, found on the membrane of rod (photoreceptor) cells of the retina, where it allows very low light intensities to be detected.

142
Q

collagen

A

fibrous

A structural protein, found in muscles, tendons and ligaments, where it gives tensile strength. It also occurs in skin and bones, where it prevents tearing and fractures, respectively.

143
Q

spider silk

A

fibrous

A fibrous protein produced by spiders for their webs. It can be extended and is very resistant to breaking.

144
Q

what is lost via denaturation

A

secondary and tertiary structures
The hydrogen bonds formed between R-groups of amino acids and amino groups of different amino acids are disrupted. Active sites lose their shape. As a result, the whole enzyme loses its enzymatic properties.

145
Q

how to denature proteins

A

temp pH

146
Q

what does pH break

A

the bonds between the non-adjacent amino acids or between the polypeptide chains of quaternary proteins.

147
Q

what is the special area on an enzyme where the actual catalytic reaction takes place

A

active site

148
Q

what is meant by enzyme–substrate specificity

A

one enzyme can only catalyse one type of reaction.

149
Q

induced fit

A

where the enzyme changes shape slightly to fit the substrate more tightly

150
Q

enzymes are

A

biological catalysts
globular proteins that can speed up a biochemical reactioj

151
Q

benefit of the induced fit

A

the enzyme induces the weakening of bonds within the molecules of the substrate(s), thus reducing the activation energy needed for the reaction. When the enzyme-catalysed reaction is completed, the products are released from the enzyme.

152
Q

How enzymes lower the activation energy.

A
153
Q

effect of low temp on enezymes

A

When temperature is low, molecules tend to move slowly. The chance of collision between substrate and enzyme molecules is also low.

154
Q

effect of mid to high temp pn enzymes

A

When temperature rises, molecules move more rapidly and it is more likely that they will collide with each other. Each enzyme has an optimum temperature in which the rate of enzymatic reaction is the highest. The optimal temperature for human enzymes is around 37   °C.

155
Q

effect of substrate conc on enzyme rate of reaction

A

When the substrate concentration is low, there are more enzyme molecules available than substrate. The rate of reaction is relatively low. Increasing the substrate concentration causes more chances of collision between substrate and enzyme molecules. Hence, the rate of enzymatic reaction rises gradually. However, this increase is halted when all active sites are occupied by substrate molecules. After this point, adding more substrate does not affect the rate of reaction.

156
Q

stomach pH

A

2

157
Q

small intenstine pH

A

7.5

158
Q

what parts of the enzyme are destroyed by denaturation

A

teritary or quaterynary, maybe even secndary

159
Q

what is immobilisation

A

a process of attaching an enzyme to a material so that its movements are restricted.

160
Q

adv of immobilising enzymes

A

if not, they are often present in the final product, which restricts the concentration that can be used to process food for human consumption to avoid adverse effects.

permits higher concentrations of enzymes to be used, allowing a faster rate of reaction.

allows immediate separation of the enzymes from the reaction mixture, which allows them to be recycled, reducing production costs.

161
Q

lactose is broken down into glucose and galactose via which enzyme

A

lactase

162
Q

The production of lactose-free products has a number of advantages:

A

no ill effects after consumption
quicker fermentation, for example, in yogurt production as bacteria ferment glucose and galactose more readily than lactose
sweeter tasting milk (glucose and galactose are sweeter tasting than lactose).

163
Q

how are lactoe free products produced

A

adding the enzyme lactase
immobilsing lactase in alginate beads whilst milk flows past

164
Q

what are dna and rna composed of

A

three parts; a pentose sugar, phosphate group and nitrogenous base

165
Q

nitrogenous bases in dna

A

agtc

166
Q

nitrogenous bases in rna

A

aguc

167
Q

differences in dna and rna

A

DNA RNA
Contains the sugar deoxyribose.
Bases involved are adenine, thymine, guanine and cytosine.
Is a double-stranded molecule.

Contains the sugar ribose.
Bases involved are adenine, uracil, guanine and cytosine (thymine has been replaced by uracil).
Is a single-stranded molecule.

168
Q

The nucleotide units link together through what

A

a phosphodiester bond (a covalent bond) to form a single strand, a polynucleotide

169
Q

What is the name of the pentose present in DNA molecules

A

deoxyribose

170
Q

omplementary base pairing rule

A

Guanine always pairs with cytosine.
Adenine always pairs with thymine.

171
Q

antiparalel concept

A

In order for bases to be facing each other, the two strands must run in opposite directions (i.e. they are antiparallel ) to each other. Thus, one strand of DNA runs from 5’ to 3’, and the opposite strand runs from 3’ to 5’. The 3’ and 5’ refer to the exposed carbon (on the sugar) at the ends of the DNA chains

172
Q

what did crick and watson do

A

They used the information from the DNA X-ray diffraction patterns produced by Rosalind Franklin and Maurice Wilkins to deduce that the DNA molecule must have a regular double helix structure.
Additionally, they integrated Chargaff’s base ratio, a finding that showed A is always equal to T and C always equal to G in the DNA molecule to work out the complementary base pairing of A to T and C to G. Once they had all the information they built a 6-foot (about 1.8 m) model out of metal scrap and, as expected, everything clicked into place. One very important aspect of using a model is the ability to visualise the molecule and to quickly see how well it fits the available evidence.

173
Q

when does the formation of a new DNA molecule occur

A

during s phase of the cell cycle

174
Q

what changes during dna rep.

A

Only the number of DNA molecules changes. It doubles after DNA replication. The chromosome number and genes stay unchanged during DNA replication.

175
Q

summary of dna replication

A

unwind the coils to make the strands accessible to enzymes. The enzyme helicase then unwinds the double helix and separates the two DNA strands by breaking the hydrogen bonds between the bases. Once the strands are separated and the bases exposed, another enzyme called DNA polymerase can start making new strands of DNA using the two ‘old parent’ strands as templates.

176
Q

why is dna semi conservative

A

because each daughter molecule formed contains one original strand from the old molecule and one newly synthesised strand.

177
Q

Conservative Model

A

– An entirely new molecule is synthesised from a DNA template (which remains unaltered)

178
Q

semi conservative model

A

Each new molecule consists of one newly synthesised strand and one template strand

179
Q

dispersive model

A

New molecules are made of segments of new and old DNA

180
Q

Meselson-Stahl Experiment

A

Nitrogen is a key component of DNA and can exist as a heavier 15N or a lighter 14N

DNA molecules were prepared using the heavier 15N and then induced to replicate in the presence of the lighter 14N

DNA samples were then separated via centrifugation to determine the composition of DNA in the replicated molecules

The results after two divisions supported the semi-conservative model of DNA replication

After one division, DNA molecules were found to contain a mix of 15N and 14N, disproving the conservative model
After two divisions, some molecules of DNA were found to consist solely of 14N, disproving the dispersive model

181
Q

transcription

A

the coding information is copied or transcribed into a special molecule called messenger RNA (mRNA). The DNA functions as a template, and the single-stranded mRNA molecule that is made follows the complementary base pairing rules of DNA, with one exception.

the section of DNA that contains the required gene is unwound and separated so that RNA polymerase enzymes can access the DNA bases. The RNA polymerase then transcribes a sequence of DNA bases into mRNA. Hence, the net product of this process is a single-stranded RNA molecule.

182
Q

Which of the following enzymes is responsible for uncoiling and separating the DNA strands during transcription?

A

RNA polymerase

183
Q

Each set of three consecutive bases in RNA is known as

A

a codon or triplet .

184
Q

what does the genetic code being degenerate mean

A

some amino acids encode more than one codon

185
Q

what does the genetic code being universal mean

A

genetic info in bacteria is translated in the same way as that of elephants, sequoia trees or any other living organisms

186
Q

trna molecuel labelled

A
187
Q

what is translation

A

the synthesis of polypeptides on ribosomes according to the genetic code

188
Q

what does trna do

A

brinds a spefcific amino acid to the mrna

189
Q

what to tran molecules have that paris with the codon of mrna

A

an anticodon

190
Q

whree does translation take place

A

in the cytoplasm

191
Q

What is the role of tRNA in translation?

A

It brings amino acids to the ribosome.

192
Q

what does pcr stand for

A

polymerase chain reaction

193
Q

what is pcr

A

a technique that can make billions of copies of one molecule of DNA by repeatedly copying a specific stretch of that DNA.

194
Q

what are plasmids

A

small circular DNA molecules in some prokaryotic cells that can be used as transfer molecules.

195
Q

waht are transgenic orgnanisms

A

Placing a gene from one organism into a different organism results in a transgenic organism.

196
Q

how is insulin produced

A

the human gene for insulin is transgerred to e. coli and results int he production of human insulin

197
Q

how are humans proteins made from plasmids

A
198
Q

respiration def

A

the gradual and controlled release of energy by breaking down organic compounds to produce ATP ( A denosine T ri P hosphate).

199
Q

3 main processes of cellular respiration

A

glycolysis
krebs
etc

200
Q

where does glycolysis take place

A

cytoplasm

201
Q

where does krebs and oxidative phosphorylation and etc take place

A

mitocohondria

202
Q

where does krebs take placae

A

matrix

203
Q

where does the etc take place

A

the inner membrane of the mitochondrial envelope

204
Q

when is energy produced

A

when atp is hydrolysed

205
Q

where does Anaerobic respiration take place

A

the cytoplasm

206
Q

which produces more oxygen

A

aerobic resp

207
Q

what does anaerobic production produce in yeast

A

alchol and co2

208
Q

alocholic fermentation formula

A

Glucose → ethanol + carbon dioxide + 2 ATP molecules

209
Q

lactic acid fermentation

A

Glucose → lactate + 2 ATP molecules

210
Q

What is the net yield of ATP produced by anaerobic respiration in yeast?

A

2 ATP molecules

211
Q

which step of aerobic respiration is the only one completed in anaerobic respiration

A

only glycolysis

212
Q

why is more atp produce in aerobic respiration

A

6-carbon glucose is systematically and gradually broken down to 6 CO 2 molecules. Each step yields potential energy, which can be converted into ATP in the electron transport chain.

213
Q

what do aerobic and anerobic respiration have in common

A

glycolysis
both generate in form of ATP
glucose as a substrate

214
Q

how would a respirometer be set up

A
215
Q

why would you set up the respirometer in a water bath

A

ensures that temperature does not affect the pressure and hence volume of air in the system

216
Q

what cna be measured with a respirometer

A

A respirometer can give us a good idea of the respiration rate of germinating seeds, a resting animal or a moving animal, and it allows us to compare different species. It can measure the influence of temperature or, for example, sleep, on respiration. The whole range of tests can be performed with such a simple setup.

217
Q

What is the role of an alkaline solution in the respirometer?

A

To absorb carbon dioxide

218
Q

why do chloroplasts look green

A

because chlorophyll a and chlorophyll b , the pigments that capture the photons, reflect green light and absorb most of the other wavelengths in the visible light spectrum

219
Q

cholorophyll absorbes waht most effectively

A

red and blue light

220
Q

The action spectrum is a good indicator of which wavelengths are most efficient in photosynthesis. Some wavelengths cause a higher photosynthetic rate than others. The action spectrum in Figure 4 shows the different rates of photosynthesis that occur at different wavelengths of visible light.

A
221
Q

When asked to draw the action spectrum, ensure that the following is included:

A

The x -axis is labelled light wavelength or frequency and the y -axis is labelled rate of photosynthesis.
The curve increases, decreases and then increases again to decrease again.
One peak is approximately at 425 nm in the blue region.
The second peak is approximately at 670 nm in the red region.
The first peak is higher than the second peak.

222
Q

The absorption spectrum of chlorophyll a and b.

A
223
Q

what is photolysis

A

he stage of photosynthesis in which water is split by light ( photo – light and lysis – splitting). The energy in photons is used to split water molecules.

224
Q

What are the electrons generated from photolysis used for

A

to generate atp

225
Q

In which process of photosynthesis is light directly involved

A

The splitting of water

226
Q

What are the products of photolysis?

A

Hydrogen ions and oxygen

227
Q

is photosynthesis anabolic or catabolic

A

anabolic

228
Q

which names are interchangeable in photosyntehsis

A

calvin cycle and light independent reactions

229
Q

Carbon dioxide + water →

A

→ carbohydrates + oxygen

230
Q

describet he two stages of photosynthesis

A

Light-dependent reaction which requires light and occurs on the thylakoids of chloroplasts. Photolysis takes place at this stage.
Light-independent reaction that has no light requirement and takes place in the stroma of chloroplasts. It involves carbon fixation to produce carbohydrates.

231
Q

What is needed in photosynthesis to convert carbon dioxide into organic molecules?

A

ATP and hydrogen from the splitting of water.

232
Q

what is a limiting factor

A

A limiting factor is a factor that restricts the rate of a reaction when present in a low amount.

233
Q

why does photosynthesis decrease at niht

A

no sun

234
Q

limiting factors of photosynthesis

A

CO2
oxygen
Sun
temp

235
Q

how is co2 a limiting factor in photosynthesis

A

Carbon dioxide is a raw material in the production of carbohydrates, which takes place in the light-independent reaction. Once all the active sites of the enzymes involved in this cyclic process are occupied with a substrate, any further increase in carbon dioxide concentration will not increase the rate (the graph levels off).

236
Q

When designing an experiment to investigate the effect of limiting factors on photosynthesis, consider the following:

A

Choose a plant material that allows easy control of variables and collection of data. Would it be better to use an aquatic plant or a terrestrial plant?
Finalise your independent variable first (it could be either temperature, light intensity or carbon dioxide concentration), then list all other variables that you have to keep constant throughout the experiment.
After checking the amount of time you have for the experiment, decide on how many levels of the independent variable you will include, as well as the number of repeats for each value. You should have at least 3–5 different levels of the independent variable.
If you have decided to measure the amount of oxygen produced as an indication of rate of photosynthesis, avoid counting bubbles; consider measuring the volume of gas produced, which is more accurate. Alternatively, you may use a data logger and oxygen or carbon dioxide sensor to collect data (if you have them at school).

237
Q

what happened when eykaryotes appeared and increased the oxygen conc underwater

A

Once the oceans and deposits were saturated, the Earth’s atmospheric oxygen started to build up. You will see that there is a peak around 300 million years before present – this coincides with the evolution of multicellular organisms and the colonisation of lan

238
Q

Which organisms contributed to the rise in oxygen concentration during the first 2 billion years of the Earth’s existence?

A

Cyanobacteria

239
Q

Name the process that accounts for the oxygen in the Earth’s atmosphere, oceans and rock depositions over the past 2 billion years.

A

photosynthesis

240
Q

phases of chromatography

A

mobile phase and a stationary phase

241
Q

what are the phasesi in paper hromatography

A

In the case of paper chromatography, the paper is the stationary phase while the solvent used to develop the chromatogram is the mobile phase. The pigments are commonly separated using an alcohol solvent mixture.

242
Q

how does chromatography work

A

The pigment is first extracted from the leaves by using a suitable solvent that dissolves most plant pigments. A sample of the extract is then placed on chromatography paper and transferred to a container with the chromatography solvent (see Figure 1 ). The pigments move at different rates on the stationary phase, so they separate out to form a chromatogram.

243
Q

Rf =

A

distance travelled by sample/distance travelled by solvent

244
Q

how can you deduce the pigments present in a plant from paper chromatography

A

By comparing the R f value to known R f values of plant pigments, the pigments present in the plant extract can be deduced.

245
Q

what is the difference in thin layer chromatographg

A

the stationary phase is usually silica gel, aluminium oxide or cellulose instead of paper.

246
Q

benefit of thin layer chroamtograpt

A

The good thing about thin layer chromatography is that it gives a better result as well-defined and well-separated spots are obtained.

247
Q

Which substance can be used to dissolve pigments in paper chromatography?

A

Ethanol

biology (13 decks)

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