B1 Flashcards
(104 cards)
1
Q
What are prokaryotic cells, With detail
A
Bacterial cells, when they replicate they form whole new organisms in which they do so through asexual reproduction
2
Q
what are cells
A
smallest unit of life that can replicate independently.
3
Q
What are eukaryotic cells
A
Animal and plant cells made from eukaryotes more complex then prokaryotes. When they replicate it results in the organism growing. contain lots of different types of cells.
4
Q
Features of a animal cell
A
Nucleas, cytoplasm, mitochondria, ribosomes, cell membrane
5
Q
Features of a plants cell
A
Everything in animal cell + rigid cell wall, chloroplasts, permanent vacuole
6
Q
Job of nucleas
A
Contains dna, controls cells activities (brain of cell)
7
Q
Job of cytoplasm
A
Site of chemical reactions in the cell
8
Q
Job of mitochondria
A
Site of respiration, contain enzymes for reactions
9
Q
Job of ribosomes
A
Where proteins are made, combination of amino acids
10
Q
Job of cell membrane
A
Hold cell together and controls what goes in and out through hormones
11
Q
Job of cell wall
A
Gives suppourt for the cell
12
Q
role for Chloroplasts
A
Site of photosynthesis
13
Q
Job of permanent vacuole
A
contain cell sap which contains substances needed for a plant cell
14
Q
Job of circular strand of DNA
A
contain genetics which the cell needs to survive and reproduce
15
Q
what do prokaryotic cells contain
A
cell membrane, cell wall, ribosomes, cytoplasm, circular strand of DNA, plasmids, flagella,
16
Q
Total mag for microscope = ?
A
Eyepiece lens x objective lens
17
Q
Image size =
A
Mag x real/ object size
18
Q
Plasmids job
A
Small loops of extra DNA, controls genes for things like drug resistance
19
Q
Chromosomal dna job
A
Controls cells activities
20
Q
What are chromosomes
A
Long molecules of Coiled up dna, divided up into small sections called genes
21
Q
role of flagella
A
a tail which allows the bacteria to move
22
Q
Four base pairings
A
A - T and G - C
23
Q
Where are proteins synthesised
A
Ribosomes
24
Q
Why’s mRNA formed
A
As strands of dna are too big, so have to break down to leave nucleas
25
whats the role of enzymes
a special type of catalyst - speed up a reaction
26
Factors that affect chemical reactions through enzymes
Temperature, pH and enzyme concentration
27
Explain how temperature affects rate of reactions in enzymes
The higher temperature, faster rates of reactions, too high and it causes the enzyme to change shape and denature
28
Explain how ph affects rate of reactions
Each reactions have different optimum pH levels, usually 7 and closer to optimum pH faster reaction
29
Explain how enzyme concentration affects rate of reactions in enzymes
More enzymes in a solution, more likely substrate will collide, increasing rate. Only too certain point as limited amounts of substrate
30
Test for optimum pH level
Add solution with different pH levels (buffer solution)
31
Definition of respiration
Process of transferring energy from breakdown of glucose into every cell in living organisms
32
What’s ATP
Energy store
33
whats metabolism
the combinations of chemical reactions in a body
34
How is respiration controlled and what factors affect rates of respiration
Controlled by enzymes so concentration of enzymes temp and pH
35
how do organisms use energy
build larger molecules from smaller ones, e.g. amino acids forming a protein
muscular contraction for movement
maintaining body temperature
36
What’s aerobic respiration
Respiration which uses oxygen, produces lots of ATP(energy)
37
Word equation for aerobic respiration
Glucose + oxygen -> carbon dioxide + water
38
Symbol equation for aerobic respiration
C6 h12 o6 + 6O2 -> 6 co2 + 6h2o
39
Factors that increase with aerobic respiration and why
Breathing rate, more oxygen to the lungs to distribute around body. Heart rate, more blood pumped around body to distribute oxygen around body
40
What’s anaerobic respiration
Respiration without oxygen
41
Word equation for anaerobic respiration in animals
Glucose -> lactic acid
42
Word equation for anaerobic respiration in plants and yeast (fungi)
glucose --> ethanol + carbon dioxide
43
When would plants respire anaerobically
When in waterlogged soil , can’t get oxygen
44
why is anaerobic respiration inefficient
incomplete breakdown of glucose due to lack of oxygen, not unlocking all energy
lactic acid build up has to be removed
45
where are carbs broken down
in the mouth and the small intestines
46
where are proteins broken down
in the stomach and the small intestines
47
where are fats broken down
small intestine
48
What are carbs made of
Simple sugars known as monomers which connect to make polymers, carbon hydrogen oxygen
49
What are monomers and polymers
Monomers make up to make polymers
50
What are protein made of
Amino acids
made from carbon, hydrogen, oxygen and nitrogen
51
What are lipids made of
glycerol and fatty acids
carbon, hydrogen oxygen
52
Diffusion examples in living organisms
Diffusion of toxic particles such as co2 in blood out of blood into lungs to out of body. Diffusion of oxygen out of lungs into blood to distribute out of body
53
What’s states a cell in when a cell loses water
Flaccid
54
What states a cell in when they gain water
Turgid
55
Difference between osmosis in animal and plant cell
Animal will pop if becomes too turgid Plant cell has a cell wall so won’t
56
What test is used for testing for sugar and explain
Benedict’s test. Turn blue if no glucose through green yellow orange and too red if has high concentration of glucose
57
What test is for lipids and explain
Emulsion test. Shake test tube with ethanol and soloution in. If lipids present will turn into milky substance
58
How is a palisade leaf cell adapted to be specialised for its job
Packed with chloroplasts for photosynthesis, at top of leaf so gets light, large sa.
59
what is the complimentary base paring unique for mRNA
a-u
60
what happens during transcription
the template strand in the DNA unzips and is replicated to form mRNA which can leave the nucleus and enter the ribosomes
61
what type of respiration is involved in making beer
anaerobic
62
what variable shows the same trend during exercise as breathing rate
heart rate
63
which type of respiration produces more ATP
aerobic respiration
64
where does photosynthesis in a plant take place
takes place in the chloroplasts, located in the leaves
65
what do the chloroplasts do
they contain chlorophyll which absorbs light energy
66
word and symbol equation for photosynthesis
carbon dioxide + water -> (light) glucose + oxygen
6CO2 + 6H2O -> (light) C6H12O6 + 6O2
67
what type of reaction is photosynthesis
endothermic
68
how does a plant absorb carbon dioxide and water
carbon dioxide diffuses into the leaf through stomata, water taken through the roots from soil and transported to the leaf through the xylem
69
what is the glucose used for by the plant
cellular respiration, breaks glucose apart to release energy
a lot of glucose combines to created cellulose which is used to strengthen cell walls
glucose combines to make starch as a long term storage for energy, used when photosynthesis is not taking place, e.g. during the night/ during the winter
70
how can the environment affect the rate of photosynthesis
disease or environmental stress and lack of nutrients, e.g. water. this can damage the chlorophyll and prevent the plant from absorbing light energy
71
what are 3 the things affecting rates of photosynthesis
light intensity, temperature, carbon dioxide concentration
72
how does light intensity affect the rates of photosynthesis
as light intensity increases, so does the rate of photosynthesis. but only increases up to a point.line flattens out on the graph , we call it plateaued, this is where something else is limiting the rate of photosynthesis e.g. co2 concentration/ temperature
73
how does carbon dioxide concentration affect the rates of photosynthesis
Higher the concentration of carbon dioxide, the higher the rate of photosynthesis. Like light it plateaus and something else becomes the limiting factor
74
how does temperature affect the rates of photosynthesis
Rate rises initially as enzymes can work quicker and molecules can move faster. Enzymes start to denature at around 37 degrees and at around 45 degrees enzymes are fully denatured and can no longer photosynthesise.
75
how to farmers optimise photosynthesis rates to produce crops faster
an example is greenhouses which traps the suns heat and increases temperature. Also use artificial light so plants can photosynthesise through the winter and the night. Farmers also use fertilisers to make sure the crops have enough minerals and use pesticides.
76
whats the photosynthesis practical
take boiling tube and measure an LED light 10cm away. fill the boiling tube with sodium hydrogen carbonate solution. place pondweed into tube placing cut end facing the surface. count bubbles of oxygen will be produced in time. Repeat to find the mean and repeat at several distances to compare light intensity.
77
why use LED lights for photosynthesis practical
LEDs don't release much heat, too much heat would alter the the temperature of the experiment
78
why use sodium hydrogen carbonate solution in test tube
releases CO2 for the pondweed
79
what is the problem with this practical
bubbles are different sizes and have different amounts of oxygen in. Also the bubbles can come too fast to count
80
how to fix these problems
measure volume of oxygen produced in measuring cylinder which has been placed above the pondweed
81
what are the 9 parts of a microscope
the base, arm, light source/ mirror, stage, the 3 objective lenses, eyepiece lens, body tube, coarse and fine focusing knob
82
in microscopy, what is the object and what is the image
the object is the real sample which you're inspecting and the image is what you see when you're looking down the microscope - magnified image
83
how do the objective lenses make the object appear bigger as an image
the lenses spread out the light rays
84
whats magnification
how many times bigger the image is than the object
85
whats resolution
the shortest distance between 2 objects can be seen without appearing blurred (a measure of how detailed the image is)
86
what are the advantages and disadvantages of using light microscopes
advantages - cheap and easy to use
disadvantages - resolution is limited to 2μm meaning any details less than 2μm cannot be viewed - cannot study sub cellular structures
87
what are the advantages and disadvantages of using electron microscopes
advantages - use electrons instead of light
resolution of up to 0.1nm (2000x better than light microscopes) so you can view sub cellular structures
disadvantages - expensive and hard to use - only used by scientists in laboratories
88
whats six kilo metres in micro, milli, metre and nano metre
6000 metres
6,000,000 milli metres
6,000,000,000 micro metres
6,000,000,000,000 nano metres
89
what 5 million nanometres in micro, milli, metres and kilo metres
5000 micro metres
5 milli metres
0.005 metres
0.000005 kilo metres
90
whats DNA
a chemical that all of our genetic materials made of
91
how many chromosomes does a human have
46, 23 pairs 1 part from mother one from father
92
what type of chromosome is the 23rd
sex chromosomes
93
which sex chromosome is male and female
female XX, male XY
94
whats a gene
a small section of DNA that codes for a protein, a small section of a chromosome
95
what do the proteins from a gene do
the protein is a sequence of amino acids, these amino acids code to make a certain type of cell, e.g. red blood cell
96
whats a genome
the entire set of genetic material in an organism
97
whats an allele
the different versions of a particular gene, one given by mother and one given by father `
98
whats a genotype
the collective allele which codes to make a characteristic
99
whats a phenotype
the characteristic you get as a result of your genotype
100
what are nucleotides
a monomer part of DNA which consists of a sugar, base and phosphate
101
whats the genetic code
the sequence of bases, a gene is a particular sequence of bases that codes for a protein, 3 bases make an amino acid and these different amino acids bind together to form a protein which carry's out a particular function
102
what are the different bases for mRNA
instead of thymine mRNA has uracil
A-U
T-A
G-C
C-G
103
how is a protein formed
3 bases code for 1 amino acid, 20 amino acids fold up to make a certain shape and code for a different protein
104
how does plants take in light intensity for photosynthesis
chlorophyll absorbs light energy
