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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