Animal and plant cells 1~5~23
Ribosomes help build proteins
Cells
A cell with a nucleus is described as eukaryotic
1 proteins✅
2 eukaryotic cells have a nucleus✅
3 nucleus ✅
4 because they are very small✅
Bacteria 1~12~23
A cell without a nucleus is described as a prokaryotic cell e.g bacteria cells.
Very small
Colourless
Need to stain them to see them
2 types of DNA
Chromosomal
Plasmid small loops
1 Nucleus, ribosomes, mitochondria ✅
2 cell wall, vacuole, chloroplast ✅
3 cell membrane✅
4 nucleus ✅
5 mitochondria✅
6 chloroplast ✅
7 to help with photosynthesis✅
8 it’s to keep the cell stood up ❌
9 to make proteins ✅
10 sex cells ✅
WWW understood gametes
EBI understand what the cell wall does
Specialised cells 1~13~23
Muscle cells
Red blood cells
White blood cells
Sperm cells
Brian cells
Egg cells
Root hair cells
Humans are multicellular organisms.
Most multicellular organisms have
SPECIALISED CELLS.
Specialised cells are cells that have a specific function. They are well adapted to carry out their function in a number of different ways. There are about 200 types of specialised cells in humans.
.
Resolution is the ability to distinguish between two points as separate structures. Essentially the level of detail can be seen using a microscope.
1 magnifies ✅
2 eyepiece lens✅
3 coarse focus wheel ✅
4
5 muscle tissue, animal cell , nucleus , protein molecules, water molecule
6 25✅
7
8 1,000✅
9 micrometer
10 nm
5/10
1,000,000,000,000
Field of view
Is were you can see down a microscope
Scale bars
Show the real length of magnified images
Magnification = eyepiece lense x objective lense
40
100
400
1000
0.01
10
a10mm
b25mm
c75mm
d600mm
e0.25mm
Enzymes are types of protein found in the body that have a very big role in the digestive system.
They need ideal conditions
Denatured - active site changes shape
Different types of enzymes “
Digestion is the breakdown of large insoluble molecules into smaller molecules.
Enzyme action 3~17~23 🍀🍀🍀🍀
1 carbohydrates
2 long chain molecule
3 glucose
4 amino acid
5 protein
6 lipids
7 spaghetti
8 breaks it down
9 energy
10 mitochondria
A protein is a large 3D molecule formed by a chain of amino acids.
Between pH 0 — 6 it also takes a long time to break down starch; the optimum pH is 7 for amylase.
Factors affecting enzyme activity 3~30~23
PH
Temperature
Substrate concentration
The enzyme and substrate are getting married because they are a perfect fit. Then the temperature gets too hot and the enzyme changes shape. Then the substrate comes back and they are both sad that they can’t get married anymore.
* 1 - where the enzyme and substrate fit
* 2 - heat pH
* 3 - where a specific enzyme and substrate fit together
* 4 -
Calorimetry 3~31~23
Measures the energy content in food.
Energy is measured in joules.
Burn the food sample
Heat the water
Measure the temperature rise
Use a lid
Use a stirrer
The simple method is not accurate because the heat can go all over the place.
Energy transferred = mass x specific heat capacity x temperature rise
Transporting substances 4~20~23
Diffusion
Diffusion is the net movement of particles from an area of higher concentration otro an area of lower concentration.
Semi permeable only some molecules can diffuse through
Diffusion is a passive process
Higher temperature higher the rate of diffusion
Why is it useful?
To get substances in and out of cells
1 Diffusion is when particles are moving from a high concentration to a low concentration.✅
2a When the temperature is increased particles gain more energy and move faster and collide with each other. ✅
2b Cells have folded membranes to increase the surface area which will mean a faster rate of diffusion.✅
Diffusion is useful for getting substances in and out of cells.
Transporting substances - osmosis
The movement of water particles down a concentration gradient, from high to low.
The water will flow from y to x because it’s going from a higher concentration to a lower concentration.
If you gain water you gain mass.
Lose water lose mass.
Active transport 5~5~23
Diffusion is the movement of particles from a high concentration to a low concentration.
Osmosis is the movement of H2O molecules from a higher concentration to a lower concentration through a semi permeable membrane.
Lungs, kidneys
Hypertonic
Hypotonic
Isotonic
shrivel up
burst
Active transport is used to move substances against the concentration gradient. It requires energy. Mitochondria produce energy by aerobic respiration.
Uses of active transport
Sugar molecules can be absorbed from lower
Percentile growth chart 5~19~23
Growth is an increase in the number of cells in an organism.
Hannah has always been taller.
1 mitosis
2a 9th
2b he is very short
3 no he is on the short side
4
5
6 blood cells to carry oxygen they have no nucleus and have a biconcave disk.
It’s so that they can check if the baby has a disease at a young age and compare it with other babies at their age.
DIRT SB1 5~26~23
Sperm
* tail - swimming to the egg
* Acrosome - break cell membrane in egg
* Haploid nucleus - fuses with an egg
Ciliated epithelial cell
* Cilia - waft an egg
* Diploid - full set of chromosomes
Similarities
* Mitochondria - release energy
* Cytoplasm - chemical reaction occur
* Nucleus -
* Cell membrane - controls substances in/out of the cell
Sperm cells have a tail which help it get to the egg, acrosome have enzymes which help it to break the cell membrane in the egg, haploid nucleus which has half the number of chromosomes. Whereas a ciliated epithelial cell has cilia which sweep an egg along an oviduct, diploid nucleus have a full set of chromosomes.
The similarities between the two cells are they both have mitochondria to give them energy, cytoplasm where the chemical reaction occurs, a nucleus which is the control centre of the cells and a cell membrane that controls what substance goes in and out of the cell.
Growth in plants 6~6~23
1 sperm cell ✅
2 nerve cells ✅
3 red blood cell
Growth in plants
1 cell division is followed by cell elongation and then cell differentiation.
2 mitosis ✅
Measuring plant growth over time
Hw
Q4a size of the potato
Q4b to keep the test fair
Q5 test tube rack, test tubes, potato, paper towel, timer, solution, weighing scale.
Q6 increase by the same percentage the
Q7 its going against the concentration gradient
Q8 its adapted to have a lot of energy.
Q3 they are adapted to have a high surface area.
Stem cells 6~13~23
A Stem Cell is a cell that hasn’t differentiated yet, they are unspecialised and can go on to become a number of different types of cell.
Stem cells are cells that have not yet differentiated. Embryonic stem cells are found in embryos and can differentiate into almost every type of human cell. Adult stem cells can only differentiate into a few types of cells. Once a cell has differentiated it can’t turn into another type of cell.
Q1 an unspecialised cells that can differentiate. ✅✅
Q2 they come from the embryo. ❌
Q3 they can differentiate. ✅
Q4 embryonic stem cells can differentiate into any type of cell.✅
Q5 They are found in bone marrow.✅
Q6 in type 1 diabetes
in cases of multiple sclerosis, which can lead to paralysis
in cases of spinal cord or brain injury, which have led to paralysis.✅
Q7 embryonic stem cells can differentiate into any type of cells whereas adult stem cells can only differentiate into a couple types of cells.✅
Q8 it can go wrong your body can reject it
The nervous system 6~20~23
1 mitosis ✅
2 embryonic stem cells ✅
3 nervous system ✅
4 diploid ✅
5 nucleus ✅
6 ribosomes ✅
7 mitochondria ✅
8 impulses ✅
9 sight,touch,taste,hearing,smell. ✅
10 brain ✅
Stimulus - A change in your surroundings that is detected by receptors, (e.g. light or sound)
Receptor Cell - A cell that detects a stimulus and converts it into an electrical impulse to be sent to the sensory neurone.
Response - An action that occurs due to a stimulus.
Receptor (cell/organ)
Stimuli
Eyes – Rods for dim light / Cones for colour vision
Light
Ears -
Sound and position of head (Balance)
Tongue -
Chemicals (e.g in food and drink) Sweet/Sour/Bitter/Savoury
Skin -
Pressure / hot / cold
Nose -
Chemicals (e.g. in air)
The nervous system sends messages throughout the body as electrical signals called impulses.
A travelling impulse is called a neurotransmission and happens in the neurones (nerve cells).
There are several different types of neurones that have different roles in the CNS.
6~28~23
Receptors cells in eye detect light from ice cube.
Impulses sent down optic nerve to brain.
Brain processes impulses and you see the ice cube.
Reflex arc doesn’t involve the brain it involves the spinal cord.
Reflex actions are automatic and do not involve the brain for any thought processing.
Reflex actions are very quick and have evolved to protect an organism from harm.
1 Vesicles fuse with presynaptic membrane.
2 Neurotransmitter (chemical messenger) released into synaptic gap.
3 Neurotransmitter diffuses across synaptic gap and is received by the receptors.
4 New electrical impulse is generated.
A synapse is a gap between two neurons. Vesicles fuse with presynaptic membrane. Neurotransmitter (chemical messenger) released into synaptic gap. Neurotransmitter diffuses across synaptic gap and is received by the receptors. A new electrical impulse is generated.
Reaction times 7~11~23
* The stimulus is the noise ❎ 0/6
Messages travel very quickly around your body through the nervous system. So you are able to respond to changes in the environment.
Practice helped me a bit
Meiosis
Alleles 10~2~23
Gene small section of DNA codes for your characteristics
Allele different form of the same gene
Dominant are always expressed and represented with a capital letter
Recessive only expressed if there are two and represented with a lower
Homozygous two of the same alleles are present
Heterozygous two different alleles are present
Genetic diagrams 10~9~23
Alleles
Alleles cause genetic variation
Homozygous
Aa
Phenotype
Genotype
Recessive
Homozygous dominant
Chance of something happening
Probability of 1 it will definitely happen
Mutations 10~11~23
Change in bases
Change in amino acid
Change in protein
Mutations happen when there is a mistake when copying DNA.
Sickle cell anaemia is caused by a gene mutation.
Pedigree charts
50%
Pedigree charts shows how genotypes are inherited in families.
Variation
M/f
W
w
w
Ww
ww
w
Ww
ww
a mutation is a change in the DNA sequence.
Polygenic means many genes.
Eye colour hair colour skin colour
Discontinuous the data can only be a limited set of values.
Continuous the data can be any value in the range.
Human genome project
Eye colour ✅
Hair length ✅
Genome - all of the DNA in an organism.
A project to decode all of the human DNA, across many countries that took 13 years.
99.9%
To identify genetic diseose, risk of lifestyle disease, personalised medicine/determine how someone might respond to medicine, ancestry, understanding human evolution
Evidence for human evolution 11~10~23
We have adapted to our lifestyle
Walk on 2 legs
Fossils soft tissues hard bones shells stones remains
60.000 years old
Evolution - the gradual change in characteristics of a species over time
Evidence for human evolution 11~15~23
The right conditions are needed to form a fossil
Fossils can be damaged by geological
How did the elephant get his trunk 11~22~23
* All organisms produce more offspring than could possibly survive
* However, population numbers tend to remain fairly constant over time
* Organisms in a species show wide variation
* Some of these variations are passed onto the next generation
* As most organisms do not survive until adulthood, all organisms must have to struggle to survive
* Those individuals with variations most adapted to their environment will have a reproductive advantage.
* Genetic Variation
* Environmental change/ Competition
* Natural Selection
* Inheritance
* Evolution
Evolution by natural selection 11~24~23
Amongst the sandpipers there is variation in beak shape due to random mutation.
EnterLonger beaked birds were more likely to survive because they had more food.
The birds reproduce and pass longer beak genes to their offspring.
Longer beaks are better adapted for getting more food.
Amongst the birds the beaks differ due to random mutation
Antibiotic resistance 11~29~23
Cacti get three spikes through evolution, some cacti have random mutations, some have genetic variation. Some cacti are better adapted to survive than others.
This is evolution.
Some bacteria have more resistance than others due to random mutation.
Bacteria with more resistance are more likely to survive when there is antibiotics and reproduce and pass their traits to their offspring meaning there will be an increase in population.
This is evolution.
Antibiotic resistance 12~1~23
Antibiotics only kill bacteria, they don’t kill viruses.
Take antibiotics for the wrong illness.
Finish your course of antibiotics early
Classification 12~6~23
So that they can produce fertile offspring.
KPCOFGS
Phataginus
Sapiens
Classification 12~8~23
1 KPCOFGS
2 Phataginus
3 Sapiens
Animals – multicellular (with cells arranged as tissues and organs), cells have nuclei, no cell walls
Plants – multicellular, have chloroplasts for photosynthesis, cells have nuclei, cellulose cell walls
Fungi – multicellular (apart from yeast), live in or on dead matter on which they feed, cells have nuclei, cell walls made of chitin
Protists – mostly unicellular (single celled organisms) cells have a nuclei, some have cell walls of different substances
Prokaryotes – unicellular, cells do not have nuclei, flexible cell walls
Kingdom
Cell wall
Nuclei
Animal
Plant
Fungi
Protists
Bacteria
Bacteria – cells with no nucleus, no unused sections in genes
Archaea – cells with no nucleus, genes contain unused sections of DNA. Usually in extreme environments
Eukarya – cells with a nucleus, unused sections in genes
Selective breeding 12~13~23
Pick two parents that have a lot of wool. Repeat this process through generations.
Choose ones with more meat and breed them through the generations
Choose the smallest and fluffiest and breed them through the generations.
Genetic modification 1~5~24
Some bacteria are more resistant to antibiotics than others due to random mutations.
Genetic engineering is when you take a gene from an organism and put it into another organism.
Genetic modification 1~10~24
It helps with blindness because it has vitamin A. Yes, they will pass the traits onto their offspring.
Advantages and disadvantages of GM 1~12~24
Bacteria can be genetically engineered to produce human insulin. The gene that codes for insulin in the human DNA the gene is removed using a restriction enzyme
2
Write more and go into more detail.
Health and disease 1~24~24
Being in a bad mood might affect your social wellbeing.
Having a disease might affect your physical wellbeing.
Feeling bad about yourself might affect your mental wellbeing.
As the amount of money you make increases the higher your life expectancy is.
Life expectancy will be greater in more developed countries because they have access to more advanced medicine and technology.
Exercising regularly can affect all of your health because you get out and about and see people, you are also helping yourself get fit.
Something that might affect someone’s mental health is that they can’t get out and see people.
The factors that make up good health are physical, mental, and social wellbeing.
Lifestyle and non-communicable diseases
The causes of malnutrition can be due to poor general diet, to little or too much of a particular nutrient for a period of time. Examples include a lack of protein leads to the deficiency disease of kwashiorkor which leads to a swollen abdomen, stunted muscle development and a failure to grow.
Cardiovascular disease
Coronary heart disease (CHD) is the leading cause of death both in the UK and worldwide.
It's responsible for more than 73,000 deaths in the UK each year. About 1 in 6 men and 1 in 10 women die from CHD.
In the UK, there are an estimated 2.3 million people living with
CHD and around 2 million people affected by angina (the most common symptom of coronary heart disease).
CHD generally affects more men than women, although from the age of 50 the chances of developing the condition are similar for both sexes.
The causes of cardiovascular diseases can be if a blood clot occurs in the coronary arteries; that provide blood to the heart, a heart attack will occur. The accumulation of bad cholesterol in the walls of arteries can cause the volume of arteries to decrease, increasing the blood pressure. Smoking increases blood pressure as the blood vessels narrow, and the chance of blood clots further increases. Increased fat in the body also increases risk.
1. To provide us with energy
2. When the body has a build up of too much fat
3. Diet, lack of exercise
4. BMI hip to waist
W:H = waist/hip
BMI = mass/ height2
Pathogens causing disease 2~21~24
1 Plant cells have a cell wall. Animal cells don’t have a cell wall. Bacteria cells don’t have a nucleus.
2
3 Magnification = image size / actual size
Preventing pathogens 2~28~24
1 bacterial virus fungi
2 antibiotics
3 headaches loss of appetite
4 cholera tb
5 weakened immune systems genetics
6 condoms
The immune system 3~6~24
Skin
mucus
Lysozymes
use hand sanitiser
wash your hands
wear a mask
White blood cells
Red blood cells transports oxygen
Lymphocytes produce memory cells
Phagocytes engulf the pathogens
Immune system the second coming 3~8~24
Red blood cells transports oxygen
Lymphocytes produce memory cells
Phagocytes engulf the pathogens
The primary response takes more time because the disease is not recognized so it takes more timid to get rid of it.
Development of medicines 3~13~24
Preclinical - Test if it kills
Test on animal cells - does it harm if cells are ok then test on actual animals
clinical trials phase 1 need volunteers
Antibodies
1 lymphocytes
2 antigens
3 memory cells
4 help protect you from that disease if it comes back
5 no
6 faster with more antibodies
7 vaccine
8 to protect us
9 antibiotics
10 pathogens
antibiotics do not harm human cells. Antibiotics destroy cell walls. Human cells do not have a cell wall.
Random mutations cause some bacteria to be more resistant
Photosynthesis 4~24~24
carbon dioxide + water —> glucose + oxygen
Used for respiration and perspiration
1 glucose ✅
2 carbon dioxide ✅
3 oxygen ✅
4a chloroplast ✅
4b absorbs light ✅
5 carbon dioxide + water —> glucose + oxygen✅
6 glucose ✅
Factors affecting photosynthesis 5~1~24
Size, length
Temperature
Catalysts
Light intensity
CO2 concentration
amount of light
light intensity increases photosynthesis increases then stays the same
CO2 concentration
CO2 concentration increases photosynthesis increases then stays the same
chlorophyll
DISEASE
(Tobacco mosaic virus)
• lack of nutrients damage
Chloroplasts
temperature
Temperature increases photosynthesis increases then it drops and enzymes begin to denature
limiting factors
The light intensity and the rate of photosynthesis 5~3~24
Light intensity and photo synthesis 5~10~24
light intensity increases photosynthesis increases then stays the same CO2 concentration increases photosynthesis increases then stays the same
Temperature increases. photosynthesis increases then it decreases. This is because enzymes begin to denature. At a certain point the rate of photosynthesis will stay the same.
Fossil fuels are burnt (expensive) to keep the greenhouse nice and warm.
Provides the optimum temperature for enzyme activity.
Lights are left on overnight to ensure
Photosynthesis is occurring during the day and night
Farmers can also add fertilisers to the soil.
This provides plants with all the key minerals needed for healthy growth.
Extra carbon dioxide can be pumped into the This comes from the burning of fuel like paraffin which releases carbon dioxide as a by-product. (This is expensive).
By keeping plants in a greenhouse this is keeping
plants away from pests and diseases.
Absorbing water and mineral ions 5~24~24
For photosynthesis
1. The shape increases surface area which helps it to absorb more water and minerals.
2. Has a thin cell wall making it easy for minerals and water to pass through.
Water and minerals
It would die
Molecules diffuse from a high concentration to a low concentration across a semipermeable membrane.
The inverse square law in photosynthesis 6~4~24
Amount of light
CO2 concentration
Chlorophyll
Temperature
As distance doubles light intensity / 2 ¼
Xylem and phloem 6~7~24
Using root hair cells and osmosis from a high to low concentration
Water - by osmosis
• High to low water molecule concentration
• Passive / no energy
• Through a cell membrane / semi-permeable
• Nutrients - by active transport
• Low to high concentration
• Requires energy
• Through a transporter protein
Xylem transpiration - water and minerals
phloem translocation - sugars
Xylem cells have very thick walls containing lignin. This provides support to the plant.
End of cell walls between the cells have broken down. Xylem cells have no chloroplasts, cytoplasm vacuole or nucleus.
The end walls do the vessel cells have pores called sieve plates
Transpiration and translocation 6~11~24
Xylem
phloem
thick walls
transports water
transpiration
water flows up
No internal structures
transports sugars
translocation
Sugars travel both ways
Little internal structures
The phloem moves food substances that the plant has produced by photosynthesis in the leaves to sink organs, where they are needed for processes such as:
growing parts of the plant for immediate use storage organs such as bulbs and tubers developing seeds
Cell sap can move from one phloem cell to the next through pores in the end walls.
Translocation is the movement of sucrose produced by photosynthesis in source organs, to sink organs such as seeds and bulbs. This occurs in phloem cells. Sucrose is transported by active transport in and out of the sieve tube cells by companion cells.
Environmental factors affecting rate of transpiration 6~14~24
Water travels through the roots to the stem and the leaves through active
Minerals absorbed by active transport into root hair cells. Water is absorbed by osmosis from an area of low concentration to high
concentration. Water evaporates out the leaves through the stomata
the flow of water into a root, up the stem and out of the leaves. Water moves up the xylem as an unbroken chain, due to forces of attraction between each molecule. As water evaporates from the leaves, more gets pulled up the stem.
DIRT
In bright light the guard cells take in water by osmosis. In low light the guard cells lose water and become flaccid.
The concentration gradient for root hair cells is form high to low
It may never disappear because one part will have a higher concentration gradient.
By osmosis.
By transpiration.
Transpiration helps to move water throughout the plant. Also helps keep plants cool.
They might be different because they live in water and not on land so they always have a source of water.
Introduction to hormones 9~9~24
1 to remove excess water? To cool down
2 shivers ✅
3 forgetting to eat ✅
Homeostasis - the constant maintenance of internal conditions to maintain optimal conditions for cellular reactions.
Respiration is the release of energy.
A gland is an organ that contains clues which produce substances.
An exocrine gland releases what it produces on to a surface, often through a tube or duct.
Adrenaline 9~10~24
Heart, lungs, liver.
Excess adrenaline can cause narrowing of the small arteries that supply the heart with blood, causing a temporary decrease in blood flow to the heart.
Adrenaline makes your heart beat faster and your lungs breathe more efficiently.
Adrenaline causes our pupils to dilate so that we can more clearly see possible threats.
Which endocrine gland is adrenaline released from? Adrenal gland.
When might adrenaline be secreted?
Name 3 target organs of adrenaline
On a mind map, show the effect of adrenaline on each of the
3 target organs identified in Q3.
Negative and positive feedback 9~16~24
Endocrine gland ✅
Homeostasis - the constant maintenance of internal conditions to maintain optimal conditions for cellular reactions.
Body temperature 37 (enzymes)
Oxygen levels (respiration)
Water levels
Blood sugar levels
If body temperature rises we sweat to cool down.
If our body temperature drops too low we shiver to warm up.
Your metabolic rate is the rate at which energy from food is transferred by all chemical reactions that take place in your body to keep you alive.
stimulation - making something more active
Inhibition - making something less active
Thyroxine controls your metabolism by stimulating cell respiration
Hormones in the human reproductive system 9~17~24
Adrenaline
Oestrogen
thyroxine
Adrenal
Sensory neuron
Relay neuron
Motor neuron
Reflex arc
Primary sexual characteristics you are born with, secondary sex characteristics start to develop at puberty.
Testosterone is the main male reproductive hormone. Produced by testes and causes sperm to be produced Oestrogen is the main hormone in females and is produced in the ovary. Together with other female hormones, it controls the menstrual cycle.
Hormones in the human reproduction system 9~30~24
There are four hormones involved in the menstrual cycle oestrogen, progesterone, LH and FSH
At the start of the cycle FSH causes the egg to develop in the follicle
FSH is released from the pituitary gland
As progesterone and oestrogen levels are low
Oestrogen levels start to rise
Oestrogen is released from the ovaries
This causes the lining of the uterus to build up
High levels cause a surge of LH
Released from the pituitary gland
Causing ovulation
An egg is released from the ovary
Progesterone is produced
From the corpus luteum
This caused the lining of the uterus to be maintained If an egg is fertilised oestrogen and progesterone levels remain high
To maintain the lining of the uterus
Corpus luteum (empty follicle)
Control of the menstrual cycle 10~1~34
Glucose, insulin and diabetes (part 1) 10~7~24
Too little sugar:
In dilute sugar solutions, osmosis can cause animal cells, such as red blood cells, to swell up and burst. This is called lysis.
Too much sugar:
In concentrated sugar solutions,
Water loss causes the cells to shrink. When this happens to red blood cells, it is called crenation.
Diabetes (part 1) 10~8~24
We control blood sugar levels in the body by producing glucose or glucagon.
Glucagon makes the liver convert glycogen to glucose for energy.
Insulin stimulates cells to take in glucose, without insulin cells do not take up glucose.
peeing more than usual, particularly at night
feeling thirsty all the time
feeling very tired
losing weight without trying to
itching around your penis or vagina, or repeatedly getting thrush
cuts or wounds taking longer to heal
blurred vision
Pancreas
Insulin
It is stored in the blood
Glucose, insulin and diabetes (part 2) 10~14~24
Type 1
type 2
pancreas does not produce enough insulin.
Diagnosed in children and teenagers
Genetic factors / damage to pancreas
cells stop responding to insulin
Usually affects 40+
Genetic tendencies linked to obesity / higher sugar diet
An advantage of changing lifestyle is you become healthier.
A disadvantage of taking medicine could have side affects.
But medicine is effective much faster.
BMI = mass / hight2
The graph increases between 1980 and
Urine testing 10~15~24
Test the bold sugar levels
Urine test
Use Benedict's solution
Type one can have medication
Type two can have lifestyle changes.
Why do organisms need to trenasport substances? 11~4~24
Oxygen to the whole body
Respiration: chemical reaction releasing energy
Specialised exchange surface
Short distances
Maximum area - high surface area
Concentration gradient
DIRT
Blood vessels heart liver
4 98% of pregnancies prevented.
The hormonal pill / implant is the most successful
release hormones to prevent ovulation and thickens mucus at the cervix, making it difficult for sperm cells to pass through
The ovaries are stimulated with hormones to increase the chance of pregnancies.
Clomifene is a drug that helps to increase the concentration of FSH and LH in the blood.
Why do organisms need to transport substances? 11~18~24
Oxygen
Glucose
Water
Carbon Dioxide
Aerobic respiration: glucose + oxygen —> carbon dioxide + water
Oxygen enters the lungs when we breath and it transported in the blood
We got glucose into the body from food and it is absorbed in the small intestine and transported through the blood
Exchange surfaces 11~19~24
Diffusion is the net movement of particles from an area of higher concentration otro an area of lower concentration.
Increase the temperature.
Factors that speed up diffusion are:
• A large concentration gradient, difference in concentration on either side of the membrane
ie. Having an efficient blood supply to maintain this concentration gradient.
• Larger surface area: volume
• short diffusion distance (thinner membrane)
Structure of blood 11~25~24
Red blood cells
White blood cells
Platelets
Diffusion is the net movement of particles from an area of higher concentration otro an area of lower concentration.
White blood cells
Oxygen
Heart dissection 12~17~24
Valves prevent backflow of blood.
Calculating cardiac output 1~6~25
It enters the heart through the vena cava then to the atria then goes through the ventricles
4 chambers of the heart
Made of muscle
Valves to stop blood flowing backwards
Coronary arteries
Pulmonary vein
Left atrium
Left ventricle
Aorta
To body
Cardiac output = stroke volume x heart rate
Aerobic respiration 1~7~25
Respiration is the chemical release of energy
Aerobic respiration is the release of energy
Cellular respiration is an exothermic, chemical reaction which occurs continuously in living cells to release energy for metabolic processes.
Respiration can include aerobic and anaerobic respiration
Mitochondria
More mitochondria
Respiration happens in the mitochondria and gets transported to the blood and transported around the body.
carbon dioxide + water —> glucose + oxygen
Glucose
Anaerobic respiration 1~14~25
carbon dioxide + water —> glucose + oxygen
Glucose —> lactic acid ( + energy )
Advantages
* doesn’t require oxygen
Disadvantage
* less efficient
* produces lactic acid - needs more energy to break down ( oxygen debt )
Glucose —> ethanol + carbon dioxide ( + energy )
Abiotic factors and communities 2~10~25
Pig
Cow
Oxygen
Carbon monoxide
Biotic
Prey
Mates
Pathogens
Abiotic
Oxygen
Temperature
Gasses concentration
Sunlight
Fire
Water
Shelter
Water will affect all organisms
Oxygen will affect all organisms
Mates will affect all organisms that reproduce
Parasites and mutalism 2~11~25
1. They all have parasites
parasites are an orginisum that lives on or in a host and causes the host harm
Tapeworms
Mutualism
Ant and acacia tree
Clown fish and enemy
Examples of parasites
Lice - animals
Ticks - animals
Misitletoe - plants
Love-vine - plants
Ringworm - fungi
Athletes foot - fungi
Parasites are an organism that lives on or in a host and causes the host harm. The survival of a parasite depends on the presence of other organisms because when the host dies, the parasite dies as well. A good example is tapeworms and humans. ✅
4/6 = 2/3
Humans and biodiversity 2~24~25
Cutting down trees
Higher population of fish overall 🐠 🐟 🎣
Dirty water
Overcrowding
Reducing biodiversity
Algae eat all the nutrients and die 💀
If there is no oxygen in the water it is Anoxic
Invasive species 2~25~25
Starter
Humans can affect biodiversity by doing things like fish farming, or cutting down trees which affect the habitat of other organisms.
Non - indigenous organism that has been introduced.
Why indigenous species might be introduced
To control invasive species in an area.
To restore the habitat of other species.
Preserving biodiversity 3~3~25
Non Indigenous ✅
Fertiliser ✅
Increase rate of growth ✅
Fish 🐠 will die ✅
Fish farming ✅
Topics to revise for biology- 1, 6, 8
11th March 2025
Revision lesson
The carbon cycle 3~18~25
Photosynthesis- Carbon dioxide + water → oxygen + glucose
Aerobic respiration- Glucose + oxygen → carbon dioxide + water
Complete combustion- Fuel + oxygen → carbon dioxide + water
Carbon in the atmosphere- greenhouse gases.
More plants( afforestation) reduces carbon dioxide.
Burning fossil fuels or deforestation affects carbon cycle
The nitrogen cycle 3~24~25
The carbon cycle is when carbon dioxide is cycled through the atmosphere.
The water cycle is when water sources evaporate water vapour condenses and turns into rain.
The nitrogen cycle (continued) 3-25-25
Quadrats and Belt Transects 3~31~25
Quadrat are used to estimate biodiversity.
* Place 10 quadrats RANDOMLY in field.
* Use a random number generator
* Count the number of each species in each quadrats.
* Calculate an average.
* Calculate size of field.
* Calculate how many of each species across the whole field.
Sunlight, rainfall, nutrients, wind.
01-04-25