Organisation of the organism/Movement into and out of cells/Biological molecules

def Tissue

a group of cells with similar structures working together to perform a shared function

def organ

A structure made up of a group of tissues working together to perform a specific function

desc the features/functions of neurones as a specialised cell

axons/long to transmit impulse over long distance fast; many branches to connect to other neurones/cells/effectors; mitochondria to release energy for transmission of impulse/protein synthesis/active transport/making neurotransmitters; vesicles to carry/hold/release neurotransmitters into synapse; receptor molecules to ensure unidirectional transmission

Explain how protein molecules move ions across a membrane during active transport

protein uses energy/ATP from respiration;

protein interacts with ions;

changes shape of protein;

ions move through protein;

against concentration gradient/lower to higher concentration across membrane

Why does wilting happen

lack of turgor pressure;

no longer a push against cell wall;

mesophyll cells not providing support/cell collapses;

cells become flaccid/plasmolyse due to lack of water

Explain how proteins are made

mRNA is made in the nucleus; mRNA is a copy of DNA; DNA stays in the nucleus; mRNA moves out into the cytoplasm; mRNA passes through ribosomes; ribosomes assemble amino acids into proteins; sequence of amino acids is determined by mRNA base sequence