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Biology > Topic 2: Molecular Biology > Flashcards

Topic 2: Molecular Biology Flashcards

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1
Q

molecular biology

A

explains living processes in terms of the chemical substances involved

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2
Q

Discover of DNA

A

1953

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3
Q

Nucleic acid

A

large biomolecules (DNA & RNA)

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4
Q

Urea

A

compound produced by living organisms but can also be synthesised.
- animals synthesis to remove excess nitrogenous waste from excess amino acids

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5
Q

Process of urea synthetisation

A

synthesised in the liver, then filtered out of the blood by the kidneys and excreted in the urine.

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6
Q

urea chemical equation

A

CO2(HN)2

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7
Q

Chemical equation of artificial urea

A

ammonia + carbon dioxide -> ammonium carbonate -> urea + water

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8
Q

falsification of vitalism

A

artificial synthesis of urea falsified vitalism

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9
Q

Vitalism

A

Only organisms can synthesis organic compounds

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10
Q

atom

A

are the basic unit of all matter

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11
Q

elements

A

substances made up of only one type atom

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12
Q

molecules

A

two or more atoms are held together by chemical bonds

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13
Q

Organic compounds

A

organisms containing these primarily have hydrogen and carbon

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14
Q

covalent bonding

A

sharing electrons between two molecules to achieve stablity

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15
Q

ionic bonding

A

attraction, one molecule take an electron from another. one molecules is positive (cation), and one is negative (anion)

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16
Q

Carbohydrates

A

most abundant organic molecules.
- are a chemical energy source
- form structural components
-form parts of DNA and RNA
-Combine with proteins to form glycoproteins and glycolipids.

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17
Q

Breaking Saccharides

A

Polysaccharides and disaccharides can be broken down into smaller molecules via hydrolysis

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18
Q

Hydrolysis

A

the splitting of the molecules with water

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19
Q

Glucose

A

involved with energy production in cell respiration
polar
carried by blood in the plasma

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20
Q

Fructose

A

a component of flower nectar to attract pollinators

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21
Q

Sucrose

A

the transport form of carbohydrates in plants (phloem)

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22
Q

Glycogen

A

storage in liver

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23
Q

Cellulose

A

the storage form of glucose found in the cell wall.

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24
Q

Examples of monosaccharides

A

Glucose, Galactose, and fructose

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25
Q

Examples of disaccharides

A

Maltose, Lactose and Sucrose

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26
Q

Examples of Polysaccharides

A

Glycogen and Cellulose

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27
Q

Proteins

A

large organic compounds made of amino acids arranged into one or more linear chains

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28
Q

Enzyme Proteins

A

Acceleration of chemical reactions

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29
Q

Transport Proteins

A

Transportation of substances

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30
Q

Structural Proteins

A

Support

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31
Q

Hormonal Proteins

A

Chemical communication with an organism

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32
Q

Receptor Proteins

A

Response of a cell to chemical messages

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33
Q

Motor Proteins

A

Movement

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34
Q

Defensive Proteins

A

Protection against disease

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35
Q

Nucleic acids

A

Chain of sub units called nucleotides

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36
Q

Simple Lipids

A

Includes Fat, Steroids and hormones, composed of Fatty Acid and Glycerol.

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37
Q

Fatty acids

A

can be saturated or unsaturated

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38
Q

Saturated Fat

A

Contained the maximum number of hydrogens with no double carbon bonds.

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39
Q

Unsaturated Fats

A

Must contain at least one double carbon bond

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40
Q

Anabolic reaction

A

builds molecules

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41
Q

Catabolic molecules

A

break down molecules

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42
Q

Anabolism

A

synthesis of complex molecules from simpler molecules

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43
Q

maltose synthase

A

condenses two molecules of glucose into maltose forming a glyosidic bond

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44
Q

Ribosomes in anabolism

A

Condeses two amino acids into a dipeptide forming a peptide bond.

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45
Q

Protease hydrolyses

A

a dipeptide into two amino acids breaking the peptide bond

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46
Q

Lactose Hydrolyse

A

Lactose into glucose and galactose breaking the glyosidic bond

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47
Q

Cohesion (water)

A
  • bonds present = tetrahedral, give cohesive force and increase strength
  • strongly cohesive tend to stick to one another
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48
Q

Adhesion (water)

A

Attract to other polar molecules

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49
Q

Solvent (water)

A
  • Polar attraction of large quantities of water molecules can interrupt intra-molecular forces and result in the dissociation of the atoms
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50
Q

Hydrophilic

A

substance attracted to water
substance that dissolves and adheres to water.

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51
Q

Hydrophobic

A

non-polar
all lipids
like dissloves like

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52
Q

amino acids

A

positive and negative chargers -
R group determines polarity and t/f solubility
carried by the blood plasma

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53
Q

oxygen

A

non polar
soluble
as temp increases, solubility decreases
at 37 degrees, little oxygen can be carried by the plasma.
haemoglobin in the red blood cells carry most oxygen

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54
Q

Fats (transport)

A

Non polar molecules
carried in blood inside lipoproteins complexs

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55
Q

Cholesterol (MB)

A

hydrophobic, apart from small hydrophilic part
carried in blood in lipoprotein complexes

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56
Q

Lipoprotein complexes

A
  • outer layer of phospholipid molecules
  • hydrophilic phosphate heads face outwards, connect with water
  • hydrophobic hydrocarbon tails face inwards connecting with fats
  • cholesterol molecules are positions in the phospholipid monolayer.
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57
Q

Sodium Chloride

A
  • ionic compound
    -freely soluble in water
    -carried in the blood plasma
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58
Q

Thermal (water)

A
  • high specific heat capcity (4.2 joules is required to increased temp by 1)
    High heat of vaporisation and fusion
    B/c hydrogen bonds need to be broken.
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59
Q

Water as a coolant

A

increased temp damages tissues and denatures proteins
takes energy to change temperature
when water evaporates, removes energy from the system. felt as cooling b/c excess heat energy is removed from the body. Skin and blood vessels are cooled.

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60
Q

difference between water and methane

A

water =polar
methane = non polar

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61
Q

methane (MB)

A
  • waste product of aerobic respiration in certain prokaryotes
  • can be used in fuel
  • contributes to the greenhouse effect
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62
Q

Methanogenic Prokaryotes

A
  • found in swamps, wetlands, and the guts of animals
  • found in waste dumps
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63
Q

monosaccharides examples

A

Glucose, Galactose, Fructose, Ribose

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64
Q

Disaccharides examples

A

Maltose, Lactose, Sucrose

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65
Q

Poly Sacchardies example

A

Cellulose, Amylose and Amylopectin, Gloceryn

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66
Q

Functions of Lipids

A

1- Energy storage
2- Subcatenos fat as a buoyancy aid and thermal insulation
3- Water proofing of hair and feather
4- Electrical conductivity

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67
Q

Energy Storage

A

mass for mass lipids produce more energy than carbohydrates

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68
Q

Water proofing of hair and feahters

A

Oil secretions from sebaceous glands in mammals and preen glands in birds preventing water logging and increase efficency of movement.

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69
Q

Electrical conductivity

A

myelin lipids of Schwann cells are involved in neurosignal transduction.

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70
Q

Cis-ismoers properties

A
  • common
    -double bond becomes bend in a fatty acid chain
    -loosely packed
    -triglycerdies formed typically liquid at room tempature
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71
Q

TRans-simoers

A

-Rare
-double bond doesn’t bend
-closely packed
-trigyclerins are typically soild at room tempature.

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72
Q

Draw the amino acid strucutre

A
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73
Q

fibrous protein properties

A

-long and narrow
-structural
-insouble in water
-repetitive amino acid
-less sensitive to change in temp, PH

74
Q

Globular proteins

A

-round/spherical
- functional
-soluble in water
-irregular amino acids
-more senstive to change

75
Q

Protein uses: CAtalysis

A

there are thousands of different enzymes to catalyse specific chemical reactions within or outside a cell

76
Q

protein uses: Muscle contraction

A

actin and myosin together cause the muscle contraction used in locomotion and transport around the body

77
Q

Protein uses: Cytoskeletons

A

tubulin is the subunit of microtubules that give animals cells their shape and pull on chromsones during mitosis

78
Q

Protein uses: Tensile strength:

A

Fibrous proteins give tensile strength needed in skin, tendons, ligaments and blood vessel wall

79
Q

Protein uses: Blood clotting

A

plasma proteins act as clotting factors that cause blood to turn from a liquid to a gel in wounds

80
Q

Protein uses: Transport of nutrients and Gases

A

Proteins in blood help transport oxygen, carbon dioxide, iron and lipids

81
Q

Protein uses: Cell adhesion

A

membrane proteins cause adajacent animals cells to stick to each other within tissues

82
Q

Protein uses: Membrane transport

A

Membrane proteins are used for facilitated diffusion and active transport, during cell respiration and photosynthesis

83
Q

Protein uses: Hormones

A

some such as insulin, FSh and LH are protein but hormones are chemically diverse

84
Q

Protein uses: Receptors

A

Binding sits in membrane and cytoplasm for hormones, neurotransmitters, taste and smells and also receptors for light in the eye and in plant.

85
Q

Protein uses: Packing of DNA

A

Histones are associated with DNA in eukaryotes and help chromosomes to condense during mitosis

86
Q

Protein uses: Immunity

A

This is the most diverse group of proteins as cells can make huge numbers of different antibodies

87
Q

Rubisco

A

Enzyme- catalyses the reaction that fixes carbon dioxide in the atmosphere.
-provides carbon for most organisms.

88
Q

Insulin

A

hormone- signals many cells to absorb glucose and help reduce the glucose concentration of the blood

89
Q

Immunglobins

A

two antigen binding sites - a molecules on the pathogen which invokes a immune response

90
Q

Rhodopsin

A

-pigment that absorbs light
-membrane protein of rod cell of the retina
-consists of the opsin polypeptide surrounding the retinal prosthetic group.

91
Q

Collagen

A
  • rope like proteins made of three polypeptides wound togehter
    -1/4 of protein in human body is collagen
    -forms a mesh of fibres in skin and in blood vessel walls that resists tearing
92
Q

spider silk

A

different silk=different functions
dragline silk is strogner than steel and tougher than kelvar
- when first made it contains regions where the polypeptide forms parallel arrays and some regions resemble a distored tangle
-when stretched the poypeptide extends make the silk extensible and resistant to breakage

93
Q

genome

A

all of the genes of a cell, a tissue or an organism

94
Q

Proteome

A

all of the proteins produced by a cell, tissue or an organism

95
Q

Denaturation of protein

A

ITs irrevisble and caused by heat, extreme ph condtions

96
Q

Denatuation of proteins: Heat

A

heat can cause denaturation: vibrations within the molecule breaks intramolecular bond or intereactions.

97
Q

Denaturation of proteins: PH

A

extremes of ph: charges on R group are changed bresking ionic bonds within the protein or causing new ionic bonds to form.

98
Q

Metabolism functions

A

overall chemical activity of your cells
- synthesising biomolecules
-energy formation and transformation
-recycling materials
-breaking down unwanted materials

99
Q

Enzymes

A

-Proteins
-Substrate specific
-Reusable
-Effective in small amounts
-Reduce the activation energy of a reaction
-able to catalyse the reaction both ways
-not able to change the direction of the reaction
-not able to change the final amount of the reaction

100
Q

Enzyme activity

A

enzyme catalysis involves molecular motion and the collision of substrate with the active site.

101
Q

Three stages of enzyme activity

A
  1. The substrate bind to the active site of the enzyme (this forms the enzyme-substrate complex)
  2. Chemical bonds in the substrates are stressed and new bonds form between substrate molecules (or bonds in a large substrate are broken)
  3. the products seperate from the active site, leaving it vacant to catalyse another reaction
102
Q

Collision theory

A

a reaction will only happen if the particles have the correct orientation and enough energy

103
Q

Factors affecting enzyme activity

A

-tempature
-pH
-inhibtion
amount of reactant
coenzymes and cofactors

104
Q

Temperature (enzyme activity)

A

adding heat increases enzyme reactions as the molecules are moving around faster and colliding more often.
too much heat can damage the structure of the enzymes and denature the enzyme.

105
Q

pH (enzyme activity)

A

shape of proteins can be affected by pH, altering the fit between the enzyme and the substrate
pH is a measure of hydrogen ions.
Enzymes shape is often created with hydrogen bonds.

106
Q

Substrate and product concentration (enzyme activity)

A

increasing the concentration of the substrate will increase the amount of reactions until the enzyme becomes saturated, adding more enzymes will fix this.,

107
Q

how lactose free milk is made

A
  1. make the enzyme lactase with bacteria. insert the gene that codes for the enzyme into the genome of a bacteria plasmid and let the bacteria create the enzyme vis protein synthesis
  2. immobilise the enzyme and combine with the milk, enzymes are held in place via entrapment. milk is then passed through these enzymes and the lactose is converted into lactase.
108
Q

immbolized enzymes

A

have been attached to other materials or included in aggregation so that the movement of the enzyme is restricted

109
Q

immbolisation of enzyme techniques

A

-attaching enzymes to a glass surface
-trapping enzymes in alginate gel
-bonding enzymes together to form aggregates

110
Q

Advantages of immobilized enzymes

A
  • the enzymes can be separated from the solution containing products of the reaction, stopping the reaction when needed.
    -enzyme can be retrieved and reused
    -immobilization increased the stability of the enzyme to changes in temp and pH
    -higher enzyme concentration can be used, increasing the rate of reactions.
111
Q

chloroplast structure

A

membranous structure: outer and inner membrane, plus thylakoid structure composed of membrane.
Fluid filled
Enzymes needed for photosynthesis reactions located in the fluid matrix (stroma)
usually twice as long as wide

112
Q

Draw a chloroplast diagram

A

look at book

113
Q

photosynthesis

A

energy conversion, as light energy is converted into chemical energy in carbon compounds

114
Q

carbohydrate at the end of photosynthesis

A

3-carbon molecule
glyceraldehyde-3-phosphate, G3P
this is converted into glucose and also used to make fatty acids and amino acids.

115
Q

draw the G3P diagram

A

check diagram

116
Q

ATP equation

A

two phases, first aborbing and converting the required energy to chemical energy.
then the second phase.
equation:
carbon dioxide+ water -> carbohydrate +oxygen

117
Q

light dependent reactions

A

occur within thylakoid membranes, chlorophyll absorbs light energy, light energy converted to ATP and NADPH. energy sources for light independent reactions, water is the source of hydrogen required for glucose.

118
Q

light independent reactions

A

occur in fluid filled stroma, the reactions are endergonic and use ATP and NADPH previously produced
ADP- low energy form of ATP
NADP+ = low energy form of NADPH
can be recycled to produce original form

119
Q

photolysis

A

light energy is used to split a water molecule to release hydrogen ions needed later, oxygen is surplus and diffused out

120
Q

photolysis of water equation

A

2H20 > 4e- + 4H+ + O2 for 2 molecules of water, half for one molecule

121
Q

effects of photosynthesis on earth

A

–increase in photosyntheic organisms and the accumulation of oxygen in the atmosphere became measure about 2.4 billion years ago and rose to 2% ( this is known as the great oxidation event) 2.2 billion years ago which it stayed until 750 million years ago. oxygen in the atmosphere decreases the methane concentration and photosynthesising organisms use up carbon dioxide. increases oxygen in atmosphere lead to increase in ocean, caused oxidation of dissolved iron in the water and the iron oxide precipitate feel onto the sea floor forming bands of iron oxide. the atmosphere since 750mya has risen to 20.05% oxygen concentration.

122
Q

limiting factors of photosynthesis

A

temperature, light intensity, and carbon dioxide concentration

123
Q

Light intensity (photosynthesis)

A

-as light intensity increases, more energy is avaliable and the rate of photosynthesis increases.
-this is a straight increase until reaching a plateau in which no further increase in co2 consumption can occur, as the light intensity cannot support the rate of reaction.

124
Q

temperature (photosynthesis)

A

rising: increasing molecular collisions due to increased kinetic energy lrads to an increase in the rate of photosynthesis.
tip: maximum rate of photosynthesis reached at the optimal temperature
too high: breaking of bond in enzymes structure leads a change in shape of the active site (denaturation) decreasing the rate of photosynthesis

-shape is a bell curve for graph.

125
Q

carbon dioxide concentration

A

positive correlation, until rate of photosynthesis reaches a plateau (plants reach saturation level with CO2) no further increase unless temperature or light intensity is increases, o possibly too little CO2 due to amount of photosynthetic organisms.

126
Q

when is visible detectable

A

from 400 to 700 nanometers

127
Q

wavelengths of light

A

red to violet, red = longest wavelength
gamma rays - long radio waves
shorter = higher energy, lower frequency = lower energy

128
Q

what light does chlorophyll absorbs

A

-red and blue light, and reflects green light. white or transparent substances don’t absorb light.

129
Q

two types of nucleic acids

A

dna: deoxyribonucleic acid
rna: ribonucleic acid

130
Q

draw a nucleotide

A

-pentose sugar, phosphate group and nitrogenous base

131
Q

difference between rna and dna (molecularly)

A

carbon two
dna: only hydrogen comming off
rna: hydroxide coming off c2

132
Q

difference between DNA and RNA

A
  • dna: double stranded
    rna: single stranded
    -dna: thymine
    rna: uracil
    dna: deoxyribose sugar
    rna: ribose sugar
133
Q

base pairings

A

adenine (b) - thymine or uracil - 2 lines
cytosine- guanine (b) - lines

134
Q

purines

A

adenine and guanine

135
Q

pyrimidines

A

cytosine, thymine and uracil

136
Q

draw dna

A

label 3’ and 5’ carbon corners, oppisite on both sides

137
Q

what type of bonding is used for nitrogenous bases

A

hydrogen bonding

138
Q

discovering the structure of dna

A

Crick and watson, used model-making to discover the structure of dna.

139
Q

DNA replication

A

the purpose of dna replication is to produce two identical copies of a dna molecule. essential for cell growth or repairable of damaged tissue. ENSURES THAT EACH NEW CELL RECIEVES ITS OWN COPY OF THE DNA

140
Q

dna helicase

A

DNA helicase separates the two polynucleotides strands of DNA by breaking the hydrogen bonds between complementary base pairs
-is required to unwind and unzip the DNA double helix.

141
Q

Dna polymerase

A

links nucelotides together to form a new strand, using pre-existing strand as a template. only copies from5’ to 3’
-catalyses the formation of a new DNA strand that is complementary in sequence to the original DNA template strand.
-DNA polymerase brings a nucleotide into a position where its base can form hydrogen bonds with the complementary base on the template strand, then catalyses a covalent bond between that nucleotide and the one before it in the new, growing DNA strand.

142
Q

stages in DNA replication

A

stage one: helicase unwinds the double helix and separates the two strands by breaking hydrogen bonds
2: DNA polymerase links nucleotides together to form new strands using the pre-existing strands as templates. completes from 3’ to 5’, which is the template. new build goes from 5’ to 3’
3: the daughter DNA molecule each rewind into a double helix

143
Q

semi conservative replication of DNA

A

each strand contains one original and one new strand. this is its own model

144
Q

conservative model

A

an entirely new molecule is synthesised from a DNA template (which remains unaltered

145
Q

semi conservative model

A

each new molecule consists of one newly synsthesised strand and one template strand

146
Q

dispersive model

A

new molecules are made of segments of new and old DNA

147
Q

Three types of RNA

A

mRNA Rrna
tRNA

148
Q

mRNA

A

serves as a temporary copy of DNA and carries the DNA codes from the nucelus to the ribosome

149
Q

rRNA

A

ribosomal rna makes up the ribosome

150
Q

tRNA

A

transfer RNA carries a specific amino acid to the ribosome and adds it to the growing polypeptide

151
Q

limitations of DNA polymerase

A
  • can not start the attachment process, as it needs a primer or is done by RNA
152
Q

PCR

A

-the polymerase chain reaction
-use of Taq polymerase to produce multiple copies of DNS, rapidly by chain reaction.
–this polymerase is obtained from a bacterium, thermus aquaticus, that lives in hot springs.
-has to be heat stable to prevent denaturation. can t/f resist the brief period of the cycle where the temp = 95, to separate DNA strands.

153
Q

PCR method

A

1: denaturation
-at 95 for 15 seconds
-double stranded DNA seperates to form two new strands.
2: attaching primer (annealing) - at 54 for 25 seconsd
primers attach to complementary sequences, so that Taq DNA polymerase can add nucelotides.
3: elongation (extending primers)
at 72 for 80 seconds, allows all single stranded DNA to be copied. 72 is the optimal tempature/
taq DNA polymerase forms a complementary strand for each template strand.

154
Q

stages in DNA polymerase

A

1: A nucleotide with the correct base is brought in by DNA polymerase.
2:Hydrogen bonds form between complementary bases.
3:DNA polymerase catalyses a covalent bond between the 5’ terminal of the new nucleotide and the 3’ terminal of the previous nucleotide.
4:DNA polymerase moves to the next nucleotide on the template strand and repeats step 1-3.

155
Q

stages in DNA polymerase

A

1: A nucleotide with the correct base is brought in by DNA polymerase.
2:Hydrogen bonds form between complementary bases.
3:DNA polymerase catalyses a covalent bond between the 5’ terminal of the new nucleotide and the 3’ terminal of the previous nucleotide.
4:DNA polymerase moves to the next nucleotide on the template strand and repeats step 1-3.

156
Q

evidence for the theory of semi-conservative replication

A

-1958, Mathew Meselson and Franklin Stahl developed a methodology to investigate DNA replication, was possible in part to to Harold Uery’s work in purifying stable isotopes for use in tracing biochemical pathways/
two isotopes of nitrogen (normal N14, and rare N15)

157
Q

evidence for the theory of semi-conservative replication

A

-1958, Mathew Meselson and Franklin Stahl developed a methodology to investigate DNA replication, was possible in part to to Harold Uery’s work in purifying stable isotopes for use in tracing biochemical pathways/
two isotopes of nitrogen (normal N14, and rare N15)
- the caesium chloride solution is centrifuged, the dense caesium ions move towards the bottom of the tubes.
-carsium ions fo not sediment fully b/c of diffusion, a concentration gradient is established.
these substances become concentrated . corresponding to density.

158
Q

Meselson and Stahl’s experiment.

A

-cultured e’coli, bacteria in a medium containing 15^N. the results concluded that all the nitrogen atoms in the DNA had denser 15^N.
bacterial was then tranffered to a medium of 14^N.
DNS samples were collected at regular time intervals for several hours, allowing for replication of DNS over four generations.

159
Q

Analysis of Meselson and Stahl’s results

A
  • demonstrated that DNA replicated semi-conservatively , meaning that each strand serves as a template for synthesis of a new, complementary strand.
    -although experimented in bacteria, we know that DNA replication is a universal mechanism.
160
Q

Gene expression

A

process by which information from a gene is used in the synthesis of a functional gene product.
The process of gene expression consists of two phases:
-Transcription, where a gene sequence is read by RNA polymerase and used to build a complementary strand of RNA
-Translation, where the RNA strand, called messenger RNA (mRNA), is read by a ribosome and used to determine the amino acid sequence of a new polypeptide

161
Q

Transcription

A

-the synthesis of mRNA copied from the DNA base sequences by RNA polymerase.
-* The strand that is transcribed is called the antisense strand and is complementary to the RNA sequence
* The strand that is not transcribed is called the sense strand and is identical to the RNA sequence (with T instead of U)

162
Q

Steps of Transcription

A
  1. RNA polymerase separates the DNA strands and synthesizes a complementary RNA copy from one of the DNA strands
  2. When the DNA strands are separated, ribonucleotide triphosphates align opposite their exposed complementary base partner
  3. RNA polymerase removes the additional phosphate groups and uses the energy from this cleavage the covalently join the nucleotide to the growing sequence
  4. Once the RNA sequence has been synthesised, RNA polymerase detaches from the DNA molecule and the double helix reforms.
163
Q

translation

A
  • Translation is the process of converting a sequence of mRNA nucleotides to a sequence of amino acids
  • This process occurs in the cytoplasm and results in a polypeptide chain (protein)
164
Q

triplets

A

group of three letters of DNA

165
Q

codon

A

-three letters of mRNA

166
Q

anticodons

A

compeltmentary to codons on tRNA

167
Q

Steps of translation

A
  1. mRNA binds to a ribosome
  2. A tRNA molecule with an anticodon that is complementary to the codon on mRNA binds to the mRNA
  3. Another tRNA with an anticodon complementary to the second mRNA codon attaches to the mRNA molecule at the ribosome
  4. An enzyme joins the two amino acids on the tRNA molecules together via a condensation reaction
  5. The bond is broken between the tRNA molecule and the amino acid that was just added to the polypeptide chain
  6. The tRNA molecule is released
  7. The ribosome moves down to the next mRNA codon
  8. This process is repeated many times to form the amino acid chain
168
Q

genetic code

A

-said to be universal
-because the same triplets make the same codons which are translated into the same amino acids in ebery single organism on earth

169
Q

what is ATP

A

adenosine triphosphate
-a high energy molecule that functions as an immediate source of power for cell processes.

170
Q

use of ATP

A

o Synthesis of macromolecules. This include DNA, RNA and proteins
o Active transport
o All movements in the cell, such as muscle contraction, endocytosis, exocytosis, etc

171
Q

anaerobic respiration

A

-oxygen not present
-glucose only
-yield of ATP per glucose per small
products:
Humans: Lactate
Yeast: CO2 and ethanol

172
Q

aerobic respiration

A

-oxygen present
-substrate is glucose or lipids
large atp yield
products: CO2 and water

173
Q

CO2 and baking

A
  • Yeast is used in baking bread. It is mixed into the dough before baking
  • The yeast rapidly uses up all oxygen present in the dough and then produces ethanol and carbon dioxide by anaerobic cell respiration. The carbon dioxide forms bubbles making the dough rise
  • It increases the volume of the bread and makes it less dense. When the dough is based most of the ethanol evaporates and the carbon dioxide bubbles give the bread a light texture
174
Q

Ethanol and brewing and biofuel industries.

A
  • Yeast can be used to produce ethanol by fermentation. The yeast is cultured in a liquid containing sugar and other nutrients, but not oxygen so its respires anaerobically
  • The ethanol concentration of the fluid around the yeast cells can rise to approximately 15% by volume, before it becomes toxic to the yeast and the fermentation ends. Most of the carbon dioxide bubbles out into the atmosphere
  • Beer, wine and other alcoholic drinks are brewed in this way
  • Ethanol is also produced by fermentation for use as a fuel
175
Q

Glycolysis

A

-all celluar respiration pathways begin with glycolysis
anaebroic process

176
Q

process of glycolysis

A
  1. Starts with glucose (6 carbons)
  2. An enzyme modifies to make it unstable
  3. A series of reactions splits the glucose into 2 molecules of pyruvate (3 carbons each)
  4. The energy from the bond that are broken in this process are used to generate 2 ATP molecules
    * To make the glucose unstable 2 ATP molecules are needed. The breaking of glucose generates 4 ATP molecules
    * So, we say that 2 ATP molecules are spent, 4 are generated, and that results in a net gain of 2 ATP molecules
177
Q

fermentations

A

-after glycolysis if no oxygen, organisms undergo fermentation.
-The breakdown of organic molecules for ATP production anaerobically
* Fermentation also takes place in the cytoplasm as it is anaerobic

178
Q

alcoholic fermentation

A

Example Organism: Yeast
1. Starts with pyruvate
2. Ends with alcohol and carbon dioxide
Real World Application: Yeast fermentation is sued to produce bread, beer and wine

179
Q

lactic acid fermentation

A

Example Organisms: Bacteria, Animals
1. Starts with pyruvate
2. Ends with lactic acid
Real World Application: Production of sour cream, yogurt, cheese, and muscle soreness after exercise in animals

180
Q

aerobic respiration

A

when oxygen is present organisms undergo aerobic respiration in the mitocondria.

Biology (6 decks)

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