YEAR 12 KNOWLEDGE Flashcards
1
Q
What is the outcome if the t-value is less than the critical?
A
<and
1. Accept null hypothesis
2. No significant difference
3. Due to chance (more than 5% probability that its due to chance)
2
Q
What is the outcome if the t-value is more than the critical value?
A
> rsn
1. Reject null hypothesis
2. Significant difference
3. Not due to chance (less than 5% chance due to chance)
3
Q
Name the components of HIV
A
- capsid
- RNA
- protein coat
- attachment proteins
- reverse transcriptase
- matrix
4
Q
Describe cellulose structure
A
- in plant cell wall
- polysaccharide
- layers of beta glucose
- weak H bonds binding together layers
- H bond together are strong
- microfibrils
5
Q
What is the role of dna polymerase
A
Form phosphodiester bonds and join nucleotides
6
Q
Differences between ATP and Nucleotides
A
- atp has 3 phosphates
-atp is ribose and nucleotides and deoxyribose
7
Q
What is the difference between endo and exosytosis
A
Endo - transporting bulk quantities of material INTO cell in vesicles
Exo - out of cell
8
Q
Role of micelles
A
- ## carry fatty acids and glycerols to cell
9
Q
Role of the Golgi apparatus
A
- processes material and package into vesicles
10
Q
What part of the molecule to all amino acids have?
A
H2N
C
H
COOH
11
Q
What is haploid?
A
Contains single, unpaired chromosomes
1…1….1….1
12
Q
What is diploid?
A
Contains 2 complete sets of chromosomes
11…11…11….11
13
Q
What is independent assortment
A
Homologous chromosomes lined up in random orientations so parent cell creates new cells with different chromosome combinations
14
Q
4 stages to crossing over
A
- homologous pairs form bivalent (2 pairs of chromosomes)
- form chiasmata (crossing over point)
- alleles exchange
- new allele combos created - genetic diversity
15
Q
Functions of mitochondria
A
- aerobic respirations
- provide atp
16
Q
5 water properties
A
- cohesion - continuous column of water through xylem
- high specific heat capacity - maintains heat internally
- high latent heat of vapour - cooling from evaporation
- metabolite
- solvent
17
Q
What is a vaccine?
A
- dead/inactive pathogen
- stimulate active immune response
- primary response
- produce memory cells
18
Q
Describe process of phagocytosis?
A
- Phagocyte detects forge in pathogen in body from receptors on cell
- Phagocyte engulfs pathogen (endocytosis) and encloses it into a vesicle (phagosome)
- Lysosomes release lysosome enzymes into the vesicle to hydrolyse the pathogen and destroy it
- The pathogens antigen are them presented onto the membrane of the phagocyte making it an antigen presenting cell and stimulating an immune response.
19
Q
What is the role of B cell is the immune response?
A
- humeral responce
- produce antibodies
1. Complimentary to an antigen
2. Once bond, b cell will take in pathogen via endocytosys
3. Then presents antigens
4. This stimulates t helper cells which bind to b cells presented antigens and to stimulate b cell cloning - plasma and memory cells.
20
Q
What are the roles of T cells in the immune response?
A
- cell-mediated responce (not direct to pathogen but instead respond to antigen presented of cell surfaces.
1. T helper cells bind to antigens on APC and divide by mitosis to produce many clones.
2. Release interleukins to stimulate replication
2. Some make memory cells
3. Cytotoxic T cells kill infected cells with PERFORIN
4. Also t helper cells stimulated by phagocytosis and active b cells.
21
Q
What is a monoclonal antibody and what they can do?
A
- Formed from cloned plasma B cells
- block antigen receptors
- carry medicines
22
Q
Steps in ELIZA test?
A
- Antibody binds to complimentary antigen
- Antibody 2 attackers with enzyme
- Solution added and colour changes due to enzyme-substrate complex.
- After each step tube rinsed to reduce excess material no bound.
23
Q
What is ATP hydrolyse?
A
- involved in co-transport
- maintains concentration greadient
- releases energy for active transport
24
Q
How does HIV develop into AIDS?
A
- no vaccine or medication
So - less antibodies produces
- t helper cells destroyed
- hiv uses cell as host to replicate and then destroys them
- few b cell stimulated
- less plasma or memory cells created so aids develops
25
What do enzymes do?
- lower activation energy
- bind and hydrolyse substrates
26
How do you calculate rate?
Change
————-
Time
27
What are polysaccharides?
- cellulose
- starch :
- amylose
- amylopectin
- glycogen
28
Amylose
- coil
- unbranded
- a glucose
- compact
- good storage
29
Amylopectin
- branched
- a glucose
- easily hydrolysed glycosidic bonds
- quick glucose release
30
Glycogen
- a glucose
- many branches
- quick energy release
- compact for storage
31
Cellulose
- long unbranched
- beta glucose layers
- chains
- weak individiual h bonds
- strong collective h bonds
- microfibrils
- structural support
32
Name the bases
Thymine
Adenine
Cytosine
Guanine
33
Species diversity definition
Large number of different species that live in same area at same time.
Species richness
34
Role of reverse transcriptase
Makes double stranded dna using dna from host cell
RNA>dna
35
Meiosis key words
Independent segregation
Homologous pairs
Crossing over
36
How does enzyme substrate complex increase activa to on energy
- reduce activation energy
- puts pressure on bonds that need to be broken
37
what reduces resolution of a microscope?
Longer light wavelength
38
How does tissue fluid form?
1. Hydrostatic pressure increases at arterial end
2. This forces fluid and solutes out of the capillary to form a tissue fluid
3. This increases the concentration of plasma proteins and lowers the water potential
4. Water then goes back back into the capillary due to the concentration gradient at the arterial end.
5. Hydrostatic pressure is also low and well as osmotic pressure .
39
Transport of sucrose in plant - How pressure changes in phloem?
1. Nutrients made in the photosynthetic cell
2. Transferred to the companion cell with actively load into phloem
3. Phloem then has a lower water potential which causes water to transfere by osmosis from the xylem into the phloem, increasing the hydrostatic pressure.
4. The sucrose and water flows down and sucrose in actively unloading into another companion cell then into the sink, reducing hydrostatic pressure, increasing water potential and causing water to move by osmosis back into the xylem.
40
Structure and job of a xylem?
- dead cells
- lignin to strengthen
- hollow
- transports water and mineral ions
41
Structure and function of phloem?
- alive cells
- sieve tube elements
- companion cell create atp
- transports nutrients of the plant up and down
42
Describe where and what the cohesion tension theory is?
- IN XYLEM
1. water lost from plant by transpiration through stomata
2. Lower water potential in cells
3. Water pulled up by xylem
4. Cohesion of water molecules stick them to each other with HYDROGEN bonds
5. This forms a water column
6. Adhesion of water to walls of xylem
43
Water potential gradient
HIGH to LOW water potential
44
Describe the sink and source?
Source - where substance is made (e.g. photosynthetic cells)
Sink - where substance is needed, used or stored
45
How does light intensity affect rate of transpiration?
- light intensity increases rate of photosynthesis
- this causes stomata to open and let in CO2
- this’s causes water to leave the stomata
46
How does wind affect the rate of transpiration?
- blows water surrounding cells away reducing the water potential around the air altering the gradient so increasing transpiration (high to low)
47
Name and explain the 4 types of immunity?
- active natural - antibodies produce from catching a virus
- active artificial - antibodies made from injected pathogen
- passive natural - antibodies obtained from mother to baby
- passive artificial - antibodies directly injected into the body
48
Difference between passive and active immunity?
Passive is much quicker
49
What is an antigen?
- a protein on the surface of a foreign pathogen that stimulates an immune responce.
50
What is an antibodies?
- a protein produced by plasma cells complimentary to a specific antigen
51
Names the types of t-cells?
- T helper - to stimulate b cells by releasing interleukins
- t memory cells - to stimulate a responce for a returned pathogen
- t killer cells - to destroy infected body cells
52
How does dna replication and describe the process of semi-conservative replication?
1. DNA HELICASE breaks H bonds and unwinds dna
2. Compliantary dna free - floating nucleotides attached to exposed bases.
3. DNA polymarise and condensation reactions Jon the new strands
4. Each new strand has one strand of new dna and one of original
53
Reducing sugar test ?
Benedict’s reagent and heat
Brick red precipitate
54
Non reducing sugar test?
- acid and gently heat
- neutralise
- Benedict’s and heat
- red precipitate
55
Monosaccharides
Glucose
Fructose
Galactose
56
Disaccharides
Sucrose (g+fru)
Lactose (g+gal)
Maltose (g+g)
57
Polysaccharides
Starch
Glycogen
Cellulose
58
3 factors affecting diffusion
- short diffusion pathway
- surface area
- diffusion gradient
59
Describe counter current flow?
- h2o from water to bloood
- more h20 in water
- maintains concentration gradient
- filaments and lamellae
60
How does gas transport around insects?
- air enters through spiracles
- air travels through trachea
- then down concentration gradient to tracheoles
- then to respiring cells
- then co2 back to spiracles
- caused by rhythmic abdominal movements
61
How do organisms prevent water loss?
- insects - close spiralces, waxy layer, hairs
- plants - curled leaves, sunken stomata, hairs , waxy cuticle, less stomata, guard cells,
62
Terms related to lung capacity?
Tidal volume - air in each breathe
Ventilation rate - breaths per minute
Forces expiratory rate - max volume out
Forced tidal capacity - max forced out
63
Lung disease
TB - mucus
Fibrosis - scar tissue
Asthma - inflamed muscle
Emphysema - alveoli wall smooth
64
Describe the cardiac cycle? And draw the diagram/graph
AS - atria contracted, ventricle relaxed, AV valves open, SL valves closed. Blood flows from atria to ventricles as pressure builds forcing blood out atria.
VS - pressure builds in ventricles causing AV valves to close, ventricle to contract, atria to relax and SL to open to allow blood to flow to artery
D - as pressure decreases as blood leaves the heart, both chambers relax and all valves close. As blood flows back into atria, pressure begins to build again forcing AV valves to open and the process repeats ….
Key words
- VOLUME
- CONTRACT/RELAX
- PRESSURE
65
WHAT DOES AMYLOSE DO
Starch to maltose !!!! (Chain to monomers)
66
How are each nutrients absorbed ?
Monosaccharides - active t with sodium ions and co transport
Fatty acids and monoglycerides - micelles, lipid soluable
Amino acids - cotransport with NA
67
Describe the relationship between partial pressure and hb afficinity for O2
Higher PP = higher AFFINITY (lungs)
Lower PP = LOWER AFFINITY (respiring cells)
68
Bohr effect
- high CO2 (from respiring cells)
- hb dissociates from O2
- shifts right
- more O2 released
- low CO2
- more hb affinity of O2
- shift left
- active organism
- low affinity
- more co2
- right shift
69
Transcription
- rna polymerase attaches to helix
- dna helicase breaks h bonds
- free nucleotides make pre mRNA
- splicing removes introns
- rna polymerase recoils dna used to make copy
- stop signal
70
Translocation
- in ribosome
- tRNA gets amino acid
- anticodon compliamentary to codon on mRNA
- amino acids coded for and makes polypeptide by bonding amino acids together with peptide bonds
- stop signal indicates end of chain
71
Types of selection
Directional selection - antibiotic resistance
- extreme and shift
Stabilisation - baby birth weight
- middle ideal
72
Mutation
Substitution
Addition or deletion
Degenerate - no effect
73
Name the inorganic ions and their functions?
Sodium - co-transport
Iron - haemoglobin
Hydrogen - determines ph
Phosphate - for ATP and DNA
74
Non-disjunction mutation
Chromosomes don’t separate fully
75
What is standard deviation?
- Tells you how much the values in a single sample vary
- (±)
- like the range of values
- represented by error bar
76
Measure of biodiversity
Species richness
77
How is biodiversity reduced
- agricultural practices
- hedgerow removal
- pesticides
- herbicides
- fertilisers
-
78
Types of carbohydrates
Monosaccharide
Disaccharide
Polysaccharide
79
Properties of monosaccharide sugars
Sweet
Soluble
Crystalline
80
How is sucrose absorbed by the gut
- no enzyme
- broken down to fructose and glucose until small enough to diffuse through cell membrane
81
How are fats processed in gut to they can be transported in the blood
Hydrolyzed and emulsified by bile
- lipase hydrolyse into fatty acids and glycerol by hydrolysing ester bonds
- micelles make smaller lipid droplets
- through ileum and reforms into triglycerides
- into lymphatic system
82
Fibrous protein in body
Keratin
Collagen
83
Conjugated protein
Protein with non protein elements in it like iron in haemoglobin
With prosthetic group
84
Prosthetic group of haemoglobin
Haem group
85
ATP
Adenosine triphospahte
86
Polarity of water molecule
- partial negative charge due to negative O and positive Hs
- charged separation
- o2 more negative
H more positive
Electrons not evenly shared
87
How to hydrogen bonds from between adjacent water molecules
- h bonds weak
- bond between o and h of adjacent water molecules
- bonds between electrostatic H and electronegative O
88
What is calcium used for in body
Muscle contraction
Synaptic transmission
89
What’s included in primary structure of a protein
- specific sequence of amino acids
- peptide bonds
90
What’s included in secondary structure of a protein
- hydrogen bonds
- folding of initial polypeptide chain
- alpha helix
- beta pleats
91
What’s included in tertiary structure of a protein
- peptide bonds
- disulfide bridges
92
What’s included in quaternary structure of a protein
- prosthetic group
- more than one polypeptide chain
93
How would a change in b base sequence of dna codons prevent enzyme function
- dna codon changes primary structure
- changed tertiary structure
- bonds change
- changes/prevetn ESC
- no longer compliamentary
94
What happens to energy not used to create atp
Lost in form of heat
95
What molecule type is atp
Nuceotide
96
Sugar in atp
Pentose
97
Role of atp in animal cells
Cell division
Active transport
Muscle contraction
98
Where in prokaryotic cells are enzymes carry out respiration
Cytoplasm
99
Differences between dna in euks and proks
Euks:
- linear dna
- associated with histogram proteins
Prok:
- alone no proteins
- as plasmids
100
Why cant viruses carry out metabolic processes
No enzymes
101
What is the role of a virus capsid and how does it protect the virus?
- not recognised by host immune system
- avoids receptors
102
How does transport of ions help prokaryote survive in fresh water?
- increases water potential in cell
- Reduces water potential gradient so less water diffuses in by osmosis
103
Outcome of binary fission
- one copy of chromosomes and some plasmids in each new cell
104
Why might division of bacteria slow ?
- accumulating waste products
- resource competition
- resource depletion - food used up
105
Which microscope shows 3D images
Scanning
106
Features of electron microscopes in general
- dead specimen
- metal grid slide
- heavy metal ions to stain specimen
- black and white image
- high magnification
- electromagnetic lens to focus
107
Prepare a slide
- this sample of specimen
- iodine dye
- cover slip
- no air bubbles
- on stage
108
How to measure a cell using eyepiece graticule and stage micrometer
- calibrate eyepiece graticule with stage micrometer
- focus on on slide and make image clear
- align cell with eyepiece graticule and measure length
- convert graticule units to actual units
109
Diffences between binary fission and mitosis
- fission is faster and has no sister chromatids or spindle fibres
- mitosis has spindle fibres and sis chromatids and has 4 clear stages
110
Stages on cell cycle
G1 - increase cell size, new organelles and MRNA
S - DNA synthesis, chromosomes replicate into chromatids
G2 - DNA checked for errors, protein synthesis
111
Polar molecule able to pass through phospholipid bilayer
Water
112
No polar substance unable to pass through phospholipid bilayer
Fat soluble material like lipids, fatty acids and glycerol
113
Membrane of vacuole
Tonoplast
114
Controls in potato osmosis experiment
- blot excess water off potatoes not absorbed
- free of peel
- completely submerged in solution
115
Why as temp increases, membrane permeability increase
- more kinetic energy
- phospholipids separate more
- denaturing proteins
- gaps form
116
How is dna created in T cell
- rna in virus converted to single dna stand
- using reverse transcriptase
- cell makes comp copy of strand
- double strand formed of dna
117
How can HIV remain dormant in human cell for many years
- part of cell genome now
-
118
How does active transport of ions help the prokaryote survive in fresh water
Increases water potential inside the cells and reduces water potential gradient so less water enters cell via mitosis
119
Why do flu vaccines remade every year
- antigenic variability
- quickly mutates
- antigenic markers on surface no longer complimentary to memory cells
120
What are cytokines and describe how they stimulate the formation of different types of B lymphocytes in order to achieve immunity.
- they are interleukins (receptors complimentary to B lymphocytes receptor)
- activates clonal expansion of B L’s
- B L’s differentiates to memory cells and plasma cells
- plasma cells secrete specific antibodies
- memory cells remain in circulation
121
Number of chromosomes in cell
46 (23 pairs)
122
Matching pairs of chromosomes
Homologous chromosomes
123
How is chromatid formed
- when dna of chromosome is replicated semi-conservatively
124
Position of gene on chromosome
Locus
125
Functional gene
Codes for protein
126
Where is dna is cell
Chloroplast
Mitochondria
Nucleus
127
Three similarities of two forms of RNA
- uracil as nitrogenous base
- ribose sugar in nucleotides
- sugar phosphate
128
Three differences of two forms of RNA
- clover vs straight
- anticodon
- amino acids binding site on tRNA
129
How does lectin chemical in parasitic plants affect protein synthesis
- enzyme inhibitor
- mutagenic agent
- changes a shape of ribosome
130
Where in meiosis is chiasmata formed
Prophase 1
131
Where does meiosis takes place
Ovaries
Testies
132
Why must gametes have haploid number of chromosomes
Gametes fuse at fertilisation so diploid number restored
133
Natural selection
- change occurs in stable environment
- random mutation giving survival advantage
- organisms without favourable allele die
- new allele passed to next generation
- organisms survive and breed
- new allele increased in frequency
134
Why is large SA:V advantageous
- lose heat energy quicky when in hot environment
135
Phylogenetic group
Some features from common ancestor
136
Taxonomy
Classification of organisms
137
Why can’t different species breed
Different calls
Different courtships
Can’t produce fertirtle offspring
138
Why does overuse of antibiotics lead to resistance
- antibiotic creates selection pressure
- nutation occurs in DNA and results in resistance
- some survive others don’t depending on mutation and favourable gene
139
Aseptic techniques
- wash hands
- sterilise apparatus, work surface
- Sterile clothes and gloves
- close windows for less circulations and currents of air
140
What is a serial dilution
- determines water potential
- several solutions of different, but known concentrations
141
How to make 5 sucrose serial dilutions
- start with 2M and dilute by factors of 3
- 5 test tubes
- 1st = 10cm3 of 2M of sucrose
- 2-5 = 5cm3 of distilled water
- 2nd = 5cm3 of first test tube - mix well (10cm3 that’s half as concentrated -1M)
- repeats 3x to create solutions of 0.5M, 0.25M, 0.125M
142
How to make sucrose solutions of any concentration
Finding scale factor
143
Using scale factor to make any concentration of sucrose e.g. 15cm3 of 4M
- start with known concentration - 1M
- find scale factor by diving the concentration of this solution by the concentration of solution wanted - 1M / 0.4M =-2.5 2.5
- solution wanted in 2.5x weaker than original
- to make 2.5x weaker, use 2.5x less of it - 15cm3 / 2.5 =-6 cm³ 6cm3
- transfer this amount and clean test tube
- top up with distilled water to get wanted volume
- want 15cm3 so add 9cm3
144
Water potential of potato cells
- cut into identical pieces (1cm diameter)
- divide into 3 groups and measure mass
- place one group into each sucrose solution made
- leave for at least 20 mins
- remove at pat dry
- and weight again
- compare difference
- calculate % change in mass + use calibration curve
- potato’s will gain water and mass in solutions with high water potential than chips
- solution with lower WP, chips lose water
145
Role of antibodies
- bind to pathogen
- agglutinate pathogens
- allows phagocytes to engulf many at once
