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1
Q

What happens at primary level?

A
  • Peptide bonds are formed.

- sequence of amino acids are formed.

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2
Q

What is at the secondary structure?

A
  • Hydrogen bonds formed

- Initial folding of polypeptide chain.

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3
Q

What is In the tertiary structure?

A
  • Overall 3D shape.

- Ioinic bonds are formed.

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4
Q

Formation of hydrogen bonds between two molecules of water?

A
  • Between O and H at adjacent molecules.
  • Between electropositive and electronegative.
  • Water molecule is polar.
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5
Q

Why is waters ability to act as a solvent important?

A
  • Supports metabolic reactions.
  • Allows ions to separate.
  • Allows organism to absorb minerals.
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6
Q

Structure of amino acids molecule,

A
  • Look in revision guide and practice
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7
Q

Structure of collagen

A
  • Peptide bonds between amino acids.
  • Every 3rd Amino Acid is glycine.
  • Three polypeptide chains.
  • Hydrogen bonds between polypeptide chains.
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8
Q

Structure of Haemoglobin

A
  • Hb is globular.
  • Hydrophobic group on inside and hydrophilic on outside.
  • 4 polypeptide chains, 2 beta and 2 alpha.
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9
Q

Which bases bind to which bases?

A
  • A-T

- C-G

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10
Q

What are the two factors which can causes variation?

A
  • Genetic.

- Environment

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11
Q

What are the use of remaining combinations?

A
  • Some are used as stop codons.

- Several triplets code for one amino acid

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12
Q

Describe the process of translation

A
  • mRNA moves to ribosomes.
  • tRNA molecule binds to mRNA.
  • Anticodons bind to codons.
  • Specific amino acids bind to codons.
  • Peptide bonds between Amino Acids are formed.
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13
Q

Structural Differences between RNA and DNA

A
  • Uracil instead of thymine.
  • RNA only had one strand, DNA had 2.
  • RNA is shorter
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14
Q

Why is complementary base pairing important?

A
  • DNA can be replicated without error.

- Allows hydrogen bonds to form.

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15
Q

Why is the glucose molecule suited to its function?

A
  • Insoluble, can be transported easily.

- Easily broken down, to produced ATP.

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16
Q

Structural similarities between deoxyribose and other components of DNA molecule.

A
  • Part of the nucleotide.

- Attached to phosphate.

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17
Q

Name the bond formed between two amino acids as how is it formed?

A
  • Peptdie bond.

- Condensation reaction between carboxyl group and amine group.

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18
Q

Where are hydrogen bonds found in biological molecules

A
  • In protein secondary structure.
  • Between polypeptide chains in tertiary structure.
  • Between chains of cellulose.
  • Between strand of DNA.
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19
Q

Roles of cholesterol in living organism

A
  • Regulates fluidity In phospholipids bilayer.

- Makes the skin waterproof.

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20
Q

How is the molecular structure of cholesterol similar to carbohydrate?

A
  • Both contains C,H and O.
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21
Q

Why is glycogen a good storage molecule?

A
  • It is compact.
  • Lots of branches for enzymes to attach to.
  • Can be broken down easily.
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22
Q

Similarities between DNA and RNA

A
  • Both have a sugar-phosphate backbone.
  • Both have four different nitrogenous bases.
  • Both contain a pentose sugar.
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23
Q

Differences between DNA and RNA

A
  • DNA contains thymine and RNA uracil.
  • DNA has double stranded, RNA is single stranded.
  • DNA only found in nucleus. RNA found in Nucleus and cytoplasm
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24
Q

Why is mRNA molecule shorter than a DNA molecule?

A
  • mRNA only copies one section of DNA.

- DNA compromises many genes.

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25
Q

How does high temperature disrupt a tertiary structure protein?

A
  • High kinetic energy.
  • Protein molecule vibrates.
  • Ionic bonds break.
  • Change in 3D shale.
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26
Q

How to test for lipids

A
  • Ethanol and water.

- Present=white emulsion.

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27
Q

How to test for reducing sugar

A
  • Benedicts solution.

- Present=Brick-red precipitate.

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28
Q

How to test for protein

A
  • Biuret I and II

- present=Lilac colour.

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29
Q

Water molecule structure

A
  • Hydrogens are delta positive.
  • Oxygens are delta Negative.
  • Hydrogen bonds between water molecules.
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30
Q

How does a Amino Acid bond on?

A
  • Peptide bonds forms.
  • Between Amine group and Carboxyl group.
  • Condensation reaction.
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31
Q

How to R groups interact to determine the tertiary structure?

A
  • Some E groups attract/repel.
  • Disulfide bonds between cysteine atoms.
  • Ionic bonds between oppositely charged R groups.
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32
Q

Structural differences between glycogen and collagen.

A
  • Glycogen= Branched. Collagen=Linear.
  • Glycogen=Non helical. Collagen=Helical.
  • Glycogen= Glycosidic bonds. Collagen=Peptide bonds.
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33
Q

Which sugar is the final products of the digestion process?

A
  • Beta glucose.
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34
Q

Why are different enzymes involved in each stage of the digestion process?

A
  • Enzymes are specific.
  • Substrates are different shapes.
  • Active site and substrates need to be complementary.
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35
Q

Explain the term biological catalyst

A

Speeds up metabolic reactions

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36
Q

What is the colour of iodine solution in the presence of starch?

A
  • Black
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37
Q

How are hydrogen bonds formed?

A
  • Between oxygen and hydrogen atoms.

- Between electronegative and electropositive molecules.

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38
Q

Effect of high temperature on the structure of the membrane

A
  • Phospholipids have more KE.
  • Larger gaps between phospholipids occur.
  • Causes phospholipids to melt.
  • Proteins denature.
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39
Q

Functions of membrane within cells.

A
  • Form vesicles.
  • Provides surface area for attachment of enzymes/ribosomes.
  • Seperates contents of Organelle and cytoplasm.
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40
Q

How does the plasma membrane contribute to cell signalling?

A
  • Release of molecule by exocytosis.
  • Glycoproteins acts as receptor.
  • Receptors are specific.
  • Shape of receptor and signal are complementary.
  • Attachment of signal molecule causes change.
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41
Q

How are vesicles move between organelles.

A
  • Cytoskeleton.
  • Move along Microtubules.
  • Uses ATP
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42
Q

Examples of active transport

A
  • Ions into root hair cells.

- hydrogen ions out of companion cells.

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43
Q

Outline the process of budding in yeast

A
  • Nucleus divides.
  • Organelles move into bulge.
  • bulge pinches off.
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44
Q

Functions of glycoproteins in the cell surface membrane

A
  • Act as antigens.
  • Act as cell receptors.
  • Cell recognition.
  • Cell adhesion.
  • Allows communication across membrane.
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45
Q

Types of cells in the phloem tissue

A
  • Companion cell.

- Sieve tube element.

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46
Q

Independent Assortment of homologous chromosomes.

A
  • Occurs in metaphase 1 and 2.

- So homologous pairs have different alleles.

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47
Q

Crossing over

A
  • Occurs in prophase 1.
  • Chromatids will have new combinations of alleles p.
  • Produces large number of allele combinations.
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48
Q

Why are new branches seen growing from a position just under the bark of the cut surface?

A
  • This is where cambium is found.
  • Mitosis occurs in cambium.
  • New cell specialised.
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49
Q

Locations where growth occurs in plants.

A
  • Cambium.

- Meristem.

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50
Q

Why does meiosis need to have twice as many stages as mitosis?

A
  • To halve the number of chromosomes.

- To separate homologous pairs.

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51
Q

What feature of DNA is changed as a result of mutation?

A
  • Sequence of nucleotides.
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52
Q

Effects mutation can have on the structure and function of proteins

A
  • Different primary Structure.
  • Can be shorter due to deletion or stop codon.
  • Can be longer due to insertion.
  • Could be unchanged due to silent mutation.
  • Function could be worse.
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53
Q

Why must genetic material replicate before mitosis?

A
  • So cells are genetically identical.

- So both cells receive a full copy of DNA

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54
Q

What is a homologous pair of chromosomes?

A
  • A pair of chromosomes which have the same genes.
  • They are the same length.
  • One maternal and one paternal.
  • Attach to each other during meiosis
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55
Q

Where can meristematic tissue found?

A
  • Apex of root.

- Apex of shoot.

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56
Q

How are products of meiosis different to the products of mitosis?

A
  • Cells produced aren’t genetically identical in meiosis.
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57
Q

How is cell division in plants different to cell division in animals?

A
  • Cell wall forms between new cells in plants.
  • Only occurs in meristem for plants.
  • No centriole in plants
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58
Q

Where in plants does cell division occur?

A
  • Meristem
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59
Q

Why are lungs considered to be an organ?

A
  • They are a group of tissues that work together.

- To carry out gas exchange.

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60
Q

Adaptations of a guard cell

A
  • A vacuole, To take up water.

- Mitochondria, to generate ATP.

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61
Q

How o alveoli create a surface for efficient gas exchange?

A
  • Wall is once cell thick, provide short diffusion pathway.
  • Squamous cells provide a short diffusion pathway.
  • Elastic fibres recoil, maintains conc. gradient.
  • Large number of alveoli provided large SA.
  • High SA:V ratio.
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62
Q

Why do large multicellular organisms needs a transport system?

A
  • Low SA:V ratio.
  • High metabolic rate.
  • Diffusion distance is too great.
  • To prevent build up of CO2.
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63
Q

ECG full name

A
  • Electrocardiagram.
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64
Q

Why is there a delay between the excitation of the atria and ventricles?

A
  • Allow time for atria to contract properly.
  • Allow time for ventricles to fill.
  • So ventricles do not contract too early.
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65
Q

Why is the excitation wave carried to the apex?

A
  • So contraction starts at the bottom.
  • To push blood upwards.
  • Complete emptying of ventricles.
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66
Q

What is tidal volume?

A
  • The volume of air taken in.

- During a normal breath.

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67
Q

Explain the process of exhalation

A
  • External intercostal muscles relax.
  • Rib cage makes upward and outwards.
  • Volume of thorax decreases.
  • Pressure in thorax increases.
  • Air leaves down pressure gradient.
68
Q

Causes of smokers cough and effects.

A
  • Damages cilia.
  • Build up of mucus in airway.
  • more pathogens accumulate.
  • cough is to increase airflow by removing mucus.
  • Lumen of airways narrows.
  • Flow of air restricted.
  • Formatoj of scar tissue
69
Q

Role of elastic fibres during ventilation

A
  • Prevent bursting.

- They recoil to Help expel air and to return air sac to its original shape.

70
Q

How do different cells and tissues enable effective gaseous exchange?

A
  • Elatic fibres expels air.
  • Squamous epithelium provides a short diffusion distance.
  • Cartilage holds open the airway.
  • Red blood cells help maintain a steep concentration gradient.
71
Q

How to use a spirometer to measure tidal volume?

A
  • Breath not through nose.
  • Person breaths normally.
  • Measure height if waves on the trace.
72
Q

How do you use a spirometer to measure oxygen uptake?

A
  • Measure the volume of o2 used.
  • Measure the time taken.
  • Divide volume by time taken.
73
Q

What happens to the air chamber during inspiration?

A
  • The aid chamber falls
74
Q

Precautions that should be made when using a spirometer

A
  • Wash the mouthpiece.

- Check the background health of the volunteer.

75
Q

Why should a person using a spirometer to measure vital capacity wear a nose clip?

A
  • to ensure all air breathed out comes from the chamber.

- To prevent entry of air through nose.

76
Q

How do the goblet cell and the Ciliated epithelial cell work together to clear dust off the lung surface?

A
  • Goblet cells release mucus.
  • Mucus traps dust particles.
  • Ciliated cell wafts mucus.
  • To back of the mouth.
77
Q

Function of smooth muscle fibres

A
  • Control flow of air.
78
Q

Why are capillaries and alveoli close together?

A
  • To maintain a steep concentration gradient.

- So the diffusion distance is not too far.

79
Q

How can the structure of bronchioles become reduced in diameter?

A
  • Contraction of smooth muscles.

- Extra mucus production.

80
Q

Why is it difficult to expel air from the lungs if the bronchioles have become reduced in diameter?

A
  • Reduced diameter means increased friction.
81
Q

How are hydrogencarbonate ions produced in the erythrocytes?

A
  • Co2 diffuses into erythrocytes.
  • Co2 reacts with water.
  • Catalyses by carbonic anhydrase.
  • Forms carbonic acid.
  • Carbonic acid dissociates to form hydrogencarbonate ions and proteins.
82
Q

Explain the Bohr effect

A
  • Co2 Reduces the affinity of Hb for oxygen.

- Prevents fall of PH in cells.

83
Q

Health definition

A
  • The physical and mental well-being of a person.

- Absence of disease

84
Q

How do components of tobacco affect the cardiovascular system?

A

Nicotine:

  • Increases stickiness of platelets.
  • Formation of blood clot.
  • Causes release of adrenaline.
  • Causes constriction of arterioles.
  • Reduced blood flow.
85
Q

Why is fetal Hb to the left of Adukt Hb on a graph?

A
  • Placenta had low po2.
  • Adult Hb will dissociate in low po2.
  • Fetal Hb has a higher affinity for oxygen.
  • Fetal Hb is able to take up more oxygen in placenta.
86
Q

How do substances such as glucose and oxygen enter the tissue fluid from capillaries?

A
  • Diffusion.
  • From high concentration to low concentration.
  • Hydrostatic pressure in capillary is greater than in tissue fluid.
  • Capillary walls are leaky.
  • Fluid forced out of capillary, small molecules leave with fluid.
87
Q

Why is lignin essential in the wall of a xylem vessel?

A
  • Provides strength to xylem vessel.
  • prevents collapse of vessel.
  • Because transpiration can cause tension.
88
Q

Why is cartilage essential in the trachea?

A
  • Supports trachea.
  • During inspiration.
  • Allows volume of thorax to increase.
89
Q

What is the mammalian blood circulatory system?

A
  • double closed
90
Q

What cuases fluctuations of blood pressure?

A
  • Contraction increases predsure.

- Relaxation decreases lressjre

91
Q

What is in arterial blood?

A
  • High hydrostaic pressure.
  • Large proteins.
  • neutrophills.
  • Erythrocytes.
92
Q

What is/isnt in tissue fluid?

A
  • Low hydrostatic pressure.
  • No large proteins.
  • Neutrophils.
  • No Erythrocytes.
93
Q

What is/isnt in lymph?

A
  • Low hydrostatic pressure.
  • No large proteins.
  • Neutrophills.
  • No erythrocytes.
94
Q

Advantages of a closed circulatory sytem

A
  • Maintain high blood pressure.

- Increase rate of flow.

95
Q

How is the artery wall adapted to withstand pressure?

A
  • Wall is thick.

- Thick layer of collagen which provides strength.

96
Q

How is an artery wall adapted to maintain pressure.

A
  • Thick layer of elastic tissue.

- Contricts lumen.

97
Q

Why is the wall of the left ventricle thicker than the wall of the left atrium?

A
  • So it can create more force.
  • Needs to create higher pressure.
  • Has to push blood against greater resistance.
  • Left ventricle pumps blood further.
98
Q

Benefits of the Bohr shift to acitvely respiring tissues.

A
  • Respiring tissues need more O2.
  • For aerobic respiration.
  • Respiring tissues produce more C02.
99
Q

Describe the role of the SAN and the AVN in coordinating the cardiac cycle

A
  • SAN initiated heartbeat.
  • SAN sends electrical impulse over atrial walls.
  • AVN delayed impulse, so atrium can contract fully.
  • AVN sends impulse down septum.
100
Q

How is the wall of an artery differnet to the wall of a vein?

A
  • Artery has no valves, veins do.

- Arteries have more collagen than veins.

101
Q

How is hydrostatic pressure generated in the heart?

A
  • Contraction of ventricle wall.
102
Q

Why does pressure of the blood decrease as blood moves away from the heart?

A
  • More vessels.
  • Vessels have larger lumen.
  • Reduced resistance to blood flow.
103
Q

What is the type of muscle found in heart chambers?

A
  • Cardiac

.

104
Q

What does a closed ciculatory system mean?

A
  • Blood is maintained inside the vessels.
105
Q

What is a single cirulatory system?

A
  • Blood passes throug the heart once for every cirulation of the body.
106
Q

How is the action of thr heart initiated and coordinated?

A
  • SAN initiates excitation.
  • Wave of excitation spreads over atrial walls.
  • AVN recieves wave of excitation.
  • Atria contracts.
  • Delay at AVN to allow atria to fully contract.
  • Excitation spreads down septum.
107
Q

Why is the excitation wave carried to the apex?

A
  • So ventricular contraction starts at the bottom.
  • To push blood upwards.
  • Complete emptying of ventricles.
108
Q

How are guard cells adapted to their role?

A
  • Unevenly thickened wall.
  • Chlorplast to provide ATP.
  • Able to bend.
109
Q

Explain the cohesion-tension theory

A
  • Evaporation at the top of the plant.
  • Creates tension in the xylem.
  • Water molecules stick together.
  • Chain pulled up by tension.
110
Q

How are companion cells adapted?

A
  • Lots of mitochondria to provide ATP.

- Plasmodesmata between companion cells.

111
Q

Difference between transpiration and transpiration steam.

A
  • Transpiration- Loss of water vapour from the stomata.

- Transpiration stream- Movement of water from the roots to the leaves.

112
Q

Why is transpiration unavoidable during the day?

A
  • Stomata are open.
  • due to high temparature.
  • Water vapours leaves.
113
Q

Adaptations of sieve tubes.

A
  • Few organeless.
  • Litlle cytoplasm.
  • Elements join end to end.
114
Q

Xylem adaptations

A
  • No end walls.
  • Lignified walls.
  • No organelles.
115
Q

How does transpiration contriubute to the mechanism of water transport up the stem?

A
  • Water loss is replaced.
  • Via apoplast pathway.
  • Down water potential gradient.
  • Lost water is replaced by water from xylem.
116
Q

Why does the potometer only give estimates of the rate of transpiration?

A
  • Potometer measured water uptake.
  • Not all water taken up is lost.
  • Some is used in photosynthesis.
117
Q

Why is water loss from the leaves of a plant unavoidable?

A
  • Stomata opens to allow gas exchange.

- For photosynthsis.

118
Q

What is meant by the terms source and sink?

A
  • Source- Site where sucrose are loaded into phloem.

- Sink- Site where sucrose are removed from the phloem.

119
Q

Explain the function of pits

A
  • Allows water to move in and out of the cell between vessels.
120
Q

Define the term parasite

A
  • Lives on a host.
  • Feeds off a host.
  • At the expense of the host.
121
Q

Why don’t primary defences work against vectors?

A
  • Vectors feeds on blood.

- Skin cannot act as a barrier.

122
Q

How does the strucute of antibodie allow them to perform their function?

A
  • 4 polypeptide chains, 2 light and 2 heavy.
  • Variable region which allows bidning to antigen.
  • Two variable regions allow binding of more than 1 antigen.
  • Constant region allows binding with phagocytes.
  • Hinge region allows flexibility.
123
Q

What is neutralisation?

A
  • Covers receptor site.

- Prevent binding of toxins.

124
Q

What is agglutanation?

A
  • Pathogens clump together.

- Clump is too large to enter host cell.

125
Q

What does bacteria become ‘immune’ to antibiotics?

A
  • Immunity involves an immuse system, which bacteria do not have.
126
Q

Why are phagocytes described as secondary defence against pathogens?

A
  • They are involved after pathogen has entered the body.
127
Q

Why is the response involving phagocytes non-specific?

A
  • Phagoyctes are able to engulf many different of pathogens.
128
Q

How is a pathfoen destroyed by a phagocyte?

A
  • Pathogen is engulfed. (Phagocytosis).
  • This forms a phagosomes.
  • Phagolysosomes fuse with eachother.
  • Enzymes in lysosomes break down the pathogen.
  • Into Amino Acid.
129
Q

How is bacteria transmitted?

A
  • Through droplets contraining pathogens.

- Released by sneezing.

130
Q

How do mosquitos transmir the malarial parasite to a human?

A
  • Mosquito is a vector.
  • Parasite present in mosquito saliva.
  • Infected mosquito feeds on human.
  • Parasite passes into blood.
131
Q

Similarities between B and T lymphocytes.

A
  • Both form part of the immune system.

- Both undergo clonal expansion.

132
Q

Differences between B and T lymphocytes

A
  • T lyphocytes are matured in thymus, B lymphocytes matured in the bone marrow.
  • T lymphocye secrete substances which kill infected cells, B lymphocytee manafacture antibodies.
  • T lymphocytes activate other lymphocytesm B lymphocytes do not.
133
Q

Difference between primary and secondary immune respones

A
  • Secondary immune responses prodcuce more antibodies.
134
Q

Memory cells function

A
  • Recognise pathogens.
  • Produce a clone.
  • Make antibodies.
135
Q

Name two primary defences and explain how they prevent entrynof pathogens into the body

A
  • Skin- Acts as a physcial barrier to prevent entrt of microorganisms.
  • Mucus- Traps pathogens
136
Q

Name the type of cell that produces antibodies

A
  • Plasma cells.
137
Q

What type of immunitt is provided by antibodies in breastmilk

A
  • Natrual Passive.
138
Q

Aims for thr convention of internarion trade in endangered species

A
  • To regulate trade of speices.

- To ensure that trade does not endanger wild populations.

139
Q

Aims of Rio Convention On Biological Diversity

A
  • Sustainable use of habitats.

- Share genetic resources.

140
Q

What is taken into account when describing the biodiversity of an area?

A
  • Species richness.
  • Species Eveness.
  • Number of habitats.
141
Q

Why is a reduction in biodiverity problematic for agriculuture in the future?

A
  • Loss of genetic diversity.
  • Agricultrual requirements may change in the future.
  • Lost genes may have been useful.
142
Q

Advantages of using a seed bank as opposed to adult plants

A
  • Are able to store more.
  • Less susceptible to disease.
  • Cheaper to transport.
143
Q

Importance of sampling

A
  • Difficult to count every specie.

- Sample provides an estimate.

144
Q

Why is important to take samples in fence and unfenced areas?

A
  • To see the effect of the specie.
145
Q

Significance of a low value of simpons index of diversity

A
  • Habitat dominated by one species.

- Habitat is less likely to cope with change.

146
Q

How is phylogeny related to classification

A
  • Phylogeny is the evolutionary histort of organisms.

- Phylogeny can allow scientists to classify species as the saem because of their physical features.

147
Q

Is the ‘Genus’ the first of the second word?

A

First

148
Q

Outline the proccess used to measure the biodiversity of plant species in grassland.

A
  • Use a quadrat.
  • Random sampling.
  • Count number of organisms in the quadrat.
  • Repeat process.
  • Calculate mean.
149
Q

Factore thr EIA consider.

A
  • Size of development.
  • Which habitats are present in the area.
  • Potential damage to organisms.
150
Q

What does the Rio convention of biological diversity do? (CBD)

A
  • Develops international stratergies on thr conservation of biodiversity.
  • Plans how ronuse animal and plant resources in a sustainable way.
  • Provides guidance to government on how to conserve biodiversity.
  • Made it a law that conserving biodiversity is everyones responsibility.
151
Q

What does the convention of international trade in endangered species (CITES) do?

A
  • Regulates trade of wild animals.
  • Members agreed to make ir illegal to kill endangered speices. (Protect endangered species).
  • Limit trade through licencing .
  • Raise awarness of threats to biodiversity.
152
Q

What does The Countryside Stewardship Scheme (CSS) do?

A
  • Promote specific management techniques.
  • Government would pay landowners who followed the management techniques.
  • As a result, species have begun to rebuild in numbers.
153
Q

Hat can be done to esnure sucdsd of breeding programmes?

A
  • Check animals health.
  • Provide food for animal.
  • Raise public awareness.
154
Q

Explain the importance of species evenness in determining biodiversity in a habitat.

A
  • Species evenness= Number of individuals in each species.
  • Higher species evenness= High biodiversity.
  • Species eveness is used to calculate simpsons index.
155
Q

Implications of a high value of simprons index of diversity on planning.

A
  • Habitat has High biodiversity.

- So should not be modified

156
Q

Now to do selective breeding?

A
  • Select best offspring.
  • Breed offspring with best offspring.
  • For mant generatons.
  • Avoid breeding closelt related individuals.
157
Q

Where is the core body tempersture is detected?

A
  • Hypothalamus.
158
Q

What is meant by the term hoemostasis?

A
  • Maintainign a stable internal enviroment.

- Around a set point.

159
Q

How is negative feedback used to cotrol an increase in blood glucose conc.?

A
  • Receptor detects increases in blood glucose conc.
  • Beta cells release insulin.
  • Increased absorption of glucose by effector cells.
  • Glucose is converted unto glycogen. (Glycogenisis).
  • Increased use of glucose in ATP production.
160
Q

How is negative feedback used to cotrol a decrease in blood glucose conc.?

A
  • Receptor detects the decrease in blood glucose conc.
  • Alpha cells release glucagon.
  • Increased conversion of glycogen to glucose. (Glycogensisis).
  • Glucose leaves cells into blood by facilitated diffusion.
161
Q

How is type 1 diabeties treated.

A
  • Daily hormone injects of insulin.

- To control blood sugar concentration.

162
Q

How it type 1 diabeties caused

A
  • Diet with high amounts of refined carbohydrates including sugars such as glucose.
  • Very little exercise.
163
Q

Describe and explain the role of ATP in the cell.

A
  • Releases 30 KJ or energy.
  • When a phosphate group is removed.
  • By hydrolysis.
164
Q

Which process is carried out by cristae?

A
  • Oxidative phosphorylation.
165
Q

Which part of thr adrenal gland releases aldosterone?

A
  • Cortex
166
Q

Explain the role od the loop of henle in the production of urine

A
  • Loops of Henle causes a decrease in water potential in medulla.
  • In acending limb, there is active transport outward of ions.
  • Descening limb is permeable to water.
  • Water potential of medulla is lower than the filtrate.
  • Water is removed from the filtrate.
167
Q

What happens at the Bowmans capsule/Glomerulus?

A
  • Ultrafiltration.