Nucleus
Controls cell
Cytoplasm
Where the chemical reactions happen
Mitochondria
Energy for the cell
Chloroplasts
Helps photosynthesis
Cell wall
Keeps cells structure
Cell membrane
Protects cells from unwanted things
Vacuole
Holds sap for cell
Diffusion
From high concentration to low
What are the two types of cells?
Eukaryotic and Prokaryotic
Plasmid
DNA molecule
flagellum
tail for swimming
ribosomes
make proteins
What are the advantages of light microscopes?
can look at live specimens
is cheap
training isnt needed
What are the disadvantages of light microscopes?
low resolutions
low magnification
needs stains
What are the advantages of electron microscopes?
view more organelles
What are the disadvantages of electron microscopes?
costs lots of money
specimens need to be in a vacuum
training is required
resolution
smallest distance between two points
magnification
the size of the object can be changed to make an image clearer
What is protein synthesis?
the creation of protein by cells that use DNA and RNA
What are the four bases in nucleotides?
Thymine
Cytosine
Guanine
Adenine
What are the complementary base pairings?
c & g
a & t
What is an enzyme?
biological catalyst
What affects the enzymes rate of reaction?
Enzyme concentration
pH
substrate concentration
temperature
What is anaerobic respiration?
Glucose — Lactic Acid
is in oxygen debt
What is aerobic respiration?
glucose + oxygen — carbon dioxide + water
supply of oxygen
What is cellular respiration?
an exothermic reaction that supplies ATP to cells
What is lipids?
is made of 3 fatty acids and glycerol and is broken down by lipase
What is protein?
A polymer made of amino acids broken down by protease
What is a carbohydrate?
a polymer made of simple sugars broken down by amylase
What is the formula of photosynthesis?
6CO2 + 6H2O → C6H12O6 + 6O
What factors affect the rate of photosynthesis?
temperature
light intensity
carbon dioxide concentration
What is a limiting factor?
factors that limit photosynthesis
What is a stem cell?
unspecialised cells capable of differentiation
What are the stem cells in plants?
Meristem cells
What are the stem cells in animals?
Adult stem cell (bone marrow) and Embryonic Stem Cells
What are three specialised animal cells?
sperm cells
muscle cells
nerve cells
What are three specialised plant cells?
root hair cells
xylem cells
phloem cells
What happens in a cell during interphase?
DNA replicates, mitosis and cytokinesis
What is active transport?
works against the concentration gradient and requires energy
What is osmosis?
water moving from one area of high concentration to areas of low concentration
What is diffusion?
particles moving from one area of high concentration to areas of low concentration
What is blood made up of?
blood is made up of plasma, white blood cells, red blood cells and platelets
What is the names of the ways that blood travel to and from the heart?
veins, capillaries, arteries and blood vessels
What do valves do in the heart?
to prevent backflow
What is the process of a double circulatory system?
right ventricle to lungs, left ventricle to the rest of the body
What are the main blood vessels of the heart?
pulmonary vein, pulmonary artery, aorta, vena cava, coronary arteries
What is transpiration?
water leaves the plants through stomata
xylem
What is translocation?
the movement of materials from leaves to other tissues throughout the plant
phloem
What are guard cells?
controls the opening and closing of the leaf
What are root hair cells?
as a thin wall and adapts for exchange
What are some exchange systems adaptations?
large surface area for gaseous exchange
thin membranes for fast diffusion
What are the five main parts of the brain?
cerebrum
hypothalamus
cerebellum
pituitary gland
medulla
cerebrum
personality and level of intelligence
hypothalamus
regulating temperature and water
cerebellum
choosing actions
pituitary gland
release hormones
medulla
blood pressure, heart and breathing rate
What are the five main parts of the eye?
iris
cornea
lens
retina
optic nerve
iris
controls the amount of light entering the eye by relaxing and contracting
cornea
focuses light to the retina by refracting
lens
refracts the light more
retina
light sensitive layer containing receptors
optic nerve
carries the messages of impulses from the brain and the eye
What are the three main eye defects?
colour blindness
myopia (lens too curved)
hyperopia (lens too flat)
What are the three types of neurons?
relay neurone
sensory neurone
motor neurone
sensory neurone
recognises the stimulus
motor neurone
takes the impulse to the effector
relay neurone
takes the information between neurones
What is a synapse?
the connector between the receptors
What is the CNS?
The spinal cord and brain
What is a receptor?
find the stimulus
What is an effector?
creates a response
What are the six main contraceptive methods?
the implant
barrier
the pill
abstinence
surgical methods
copper intrauterine device
What are the secondary characteristics at puberty?
Ovaries which produce oestrogen and testes which produce testosterone
What does the thyroid gland do?
controls the metabolic rate and is part of a feedback loop
What do the adrenal glands do?
releases adrenaline which triggers a fight or flight response which can cause breath and heart rate to increase
What are the process of IVF?
FSH is used to release oestrogen from a mature egg which is then fertilised and injected into a mothers uterus
What are the stages of the menstrual cycle?
FSH matures an egg whilst progesterone and oestrogen maintains the lining of the uterus
LH is then released which causes the egg to be released
What are the three main plant hormones?
auxins
gibberellins
ethene
What does auxins do?
promotes tissue and root growth
What do gibberellins do?
starts flowering and germination
What does ethene do?
helps fruits to ripen
phototropism
response to light
gravitropism
response to gravity
What happens when body temperature is too high?
glucose turns into glucagon
vasodilation
What happens when the body temperature is too low?
hairs stand up
shivering
What is blood glucose levels controlled by?
pancreas
What happens when the blood glucose levels are too high?
insulin is released and glucose is turned into glycogen
What happens when the blood glucose levels are too low?
glucagon is released and glycogen is turned into glucose
What is type 1 diabetes?
the pancreas cannot create insulin so insulin injections are needed
What is type 2 diabetes?
the cells cannot respond to insulin but can be combated with a healthy lifestyle
What happens when the bloods water concentration decreases?
the cell shrinks
What happens when the bloods water concentration increases?
the cell can burst
What is the function of the kidney?
to filter the blood
What is excreted from the kidney?
amino acids which are converted into urea
What does the kidney act on?
ADH is released by the pituitary gland because of low water levels and allows more to be absorbed
How does the kidney promote water loss?
sweating
salt loss
being more thirsty
What is the test for sugars?
Benedicts blue to red (precipitate)
What is the test for starch?
iodine yellow to blue-black
What is the test for protein?
Biuret blue to lilac