Paper 1 Notes

Organelles

subcellular structures

Eukaryotic

with nucleus

Nucleus

DNA, controls

Cytoplasm

contains enzymes, where most reactions happen

Mitochondria

respiration

Ribosome

protein synthesis

Cell membrane

controls what goes in and out of the cell

Nucleus

DNA, controls

Cytoplasm

contains enzymes, where most reactions happen

Mitochondria

respiration

Ribosome

protein synthesis

Cell membrane

controls what goes in and out of the cell

Cell wall

strengthens cell

Vacuole

sac filled with cell sap

Chloroplasts

photosynthesis, contains chlorophyll

Prokaryotic

without nucleus

Plasmid

where DNA is held since the cell has no nucleus

Flagellum

movement

Cell membrane

controls what goes in and out of the cell

Cytoplasm

contains enzymes

Ribosomes

protein synthesis

Chromosomal DNA

contains most of the genes

Flagellum

tail to swim

Long mitochondria

needs energy to swim to the egg

Acrosome

helps sperm penetrate the eggs jelly coat

Micrograph

image that a microscope creates

Stage

what the slide sits on

Coarse adjustment

higher dial that roughly makes the image clearer

Fine adjustment

lower dial that makes the image fully clear

Eyepiece lens

smaller magnification

Objective lens

larger magnification

Substrate

what it works on

Active site

what the substrate binds to to break it down

Catalyst

something that speeds up a reaction

Biological catalyst

something that speeds up a reaction without being used up itself

Digestive enzymes

break down large food molecules down to ones small enough to absorb

Amylase

starch (carbohydrate) → glucose

Protease

protein → amino acids

Lipase

fat → fatty acids and glycerol

Denaturing

active site has changed shape

Concentration

number of particles in a given volume

Diffusion

when molecules move from a high concentration to a low concentration (down a concentration gradient)

Osmosis

diffusion of water across a partially permeable membrane

Active Transport

movement of any substance from a low to high concentration (up a concentration gradient)

Diploid

contains 23 pairs of chromosomes

Haploid

contains 23 chromosomes

Prophase

nucleus breaks down, spindle fibres form

Metaphase

spindle fibres are fully formed and are lined up along the equator

Anaphase

pairs pulled to opposite poles

Telophase

new nucleus forms around each end, cell pinches in the middle

Cytokinesis (after mitosis)

separation of cells is completed

Stem cells

cell that can differentiate

Differentiation

when a cell divides to produce 2 types of specialised cell

Sensory

carries impulse to central nervous system

Relay

makes decisions

Motor

carries impulse from central nervous system to muscle

Chromosome

large piece of DNA

Gene

section of DNA

Dominant

one copy needed to show feautre

Recessive

2 copies needed to show feature

Homozygous

2 of the same allele

Heterozygous

different alleles

Phenotype

what you see

Genotype

genes you have

Discontinuous

genes

Continuous

genes and environment

Common ancestor

ancestor shared by 2 or more other organisms

Malnutrition

getting too much/too little of certain nutrients

Obesity

too much nutrients

Nutrient deficiency

too little nutrients

Scurvy

lack of vitamin C (swollen, bleeding gums, bone issues)

Anaemia

caused by lack of iron (lightheadedness)

Cirrhosis

liver starts to break down

Heart attacks

inside arteries, plaque builds up, blocks arteries, blood cant get through, body doesnt get as much nutrients, heart can die and the rest of the body stops getting nutrients

Pathogens

microorganisms that cause disease