Topic 2: Molecular Biology Flashcards

Question

Examples of disaccharides

Answer 1

Maltose, Lactose and Sucrose

Answer 2

Glycogen and Cellulose

Answer 3

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

Answer 4

Acceleration of chemical reactions

Answer 5

Transportation of substances

Answer 6

Chemical communication with an organism

Answer 7

Response of a cell to chemical messages

Answer 8

Protection against disease

Answer 9

Chain of sub units called nucleotides

Answer 10

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

Answer 11

can be saturated or unsaturated

Answer 12

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

Answer 13

Must contain at least one double carbon bond

Answer 14

builds molecules

Answer 15

break down molecules

Answer 16

synthesis of complex molecules from simpler molecules

Answer 17

condenses two molecules of glucose into maltose forming a glyosidic bond

Answer 18

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

Answer 19

a dipeptide into two amino acids breaking the peptide bond

Answer 20

Lactose into glucose and galactose breaking the glyosidic bond

Answer 21

- bonds present = tetrahedral, give cohesive force and increase strength - strongly cohesive tend to stick to one another

Answer 22

Attract to other polar molecules

Answer 23

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

Answer 24

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

Answer 25

non-polar all lipids like dissloves like

Answer 26

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

Answer 27

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

Answer 28

Non polar molecules carried in blood inside lipoproteins complexs

Answer 29

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

Answer 30

- 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.

Answer 31

- ionic compound -freely soluble in water -carried in the blood plasma

Answer 32

- 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.

Answer 33

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.

Answer 34

water =polar methane = non polar

Answer 35

- waste product of aerobic respiration in certain prokaryotes - can be used in fuel - contributes to the greenhouse effect

Answer 36

- found in swamps, wetlands, and the guts of animals - found in waste dumps

Answer 37

Glucose, Galactose, Fructose, Ribose

Answer 38

Maltose, Lactose, Sucrose

Answer 39

Cellulose, Amylose and Amylopectin, Gloceryn

Answer 40

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

Answer 41

mass for mass lipids produce more energy than carbohydrates

Answer 42

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

Answer 43

myelin lipids of Schwann cells are involved in neurosignal transduction.

Answer 44

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

Answer 45

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

Answer 46

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

Answer 47

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

Answer 48

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

Answer 49

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

Answer 50

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

Answer 51

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

Answer 52

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

Answer 53

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

Answer 54

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

Answer 55

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

Answer 56

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

Answer 57

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

Answer 58

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

Answer 59

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

Answer 60

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

Answer 61

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

Answer 62

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

Answer 63

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

Answer 64

- 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

Answer 65

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

Answer 66

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

Answer 67

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

Answer 68

ITs irrevisble and caused by heat, extreme ph condtions

Answer 69

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

Answer 70

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

Answer 71

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

Answer 72

-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

Answer 73

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

Answer 74

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

Answer 75

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

Answer 76

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

Answer 77

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.

Answer 78

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.

Answer 79

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

Answer 80

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.

Answer 81

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

Answer 82

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

Answer 83

- 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.

Answer 84

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

Answer 85

look at book

Answer 86

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

Answer 87

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

Answer 88

check diagram

Answer 89

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

Answer 90

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.

Answer 91

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

Answer 92

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

Answer 93

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

Answer 94

--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.

Answer 95

temperature, light intensity, and carbon dioxide concentration

Answer 96

-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.

Answer 97

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.

Answer 98

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.

Answer 99

from 400 to 700 nanometers

Answer 100

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

Answer 101

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

Answer 102

dna: deoxyribonucleic acid rna: ribonucleic acid

Answer 103

-pentose sugar, phosphate group and nitrogenous base

Answer 104

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

Answer 105

- dna: double stranded rna: single stranded -dna: thymine rna: uracil dna: deoxyribose sugar rna: ribose sugar

Answer 106

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

Answer 107

adenine and guanine

Answer 108

cytosine, thymine and uracil

Answer 109

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

Answer 110

hydrogen bonding

Answer 111

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

Answer 112

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

Answer 113

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.

Answer 114

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.

Answer 115

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

Answer 116

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

Answer 117

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

Answer 118

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

Answer 119

new molecules are made of segments of new and old DNA

Answer 120

mRNA Rrna tRNA

Answer 121

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

Answer 122

ribosomal rna makes up the ribosome

Answer 123

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

Answer 124

- can not start the attachment process, as it needs a primer or is done by RNA

Answer 125

-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.

Answer 126

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.

Answer 127

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.

Answer 128

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.

Answer 129

-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)

Answer 130

-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.

Answer 131

-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.

Answer 132

- 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.

Answer 133

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

Answer 134

-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)

Answer 135

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.

Answer 136

* 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)

Answer 137

group of three letters of DNA

Answer 138

-three letters of mRNA

Answer 139

compeltmentary to codons on tRNA

Answer 140

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

Answer 141

-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

Answer 142

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

Answer 143

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

Answer 144

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

Answer 145

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

Answer 146

* 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

Answer 147

* 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

Answer 148

-all celluar respiration pathways begin with glycolysis anaebroic process

Answer 149

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

Answer 150

-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

Answer 151

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

Answer 152

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

Answer 153

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