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Osmosis
The diffusion of water from a dilute solution to a concentrated solution across a semi permeable membrane
Turgid
When a cell is full, its contents push against the cell wall
plasmolyzed
When cells lose water and the cell membrane pulls away from the cell wall
cell membranes
Allow some substances to pass through as they are selectively permeable
How materials move in and out of cells
Diffusion, active transport, osmosis
Transpiration
The loss of water via evaporation, water diffuses out of the stomata
Functions of water in plants
Water for transpiration, photosynthesis, transport of minerals, cell support
Conditions that affect rate of transpiration
Humidity, temperature, wind conditions
Role of cell wall
Restricts water intake to prevent cell bursting
Genes
Short lengths of DNA which code for a particular characteristic or protein
Shape of DNA
Double helix
A links with
T
C links with
G
Complementary base pairing
The arrangement of bases along the length of DNA determines how a gene works
nucloetide
A building block of DNA consisting of a phosphate, sugar and a base
Genetic code
Bases along one side of the DNA molecule- the coding strand
base triplet
The sequence of bases that codes for an amino acid
Erwin Chargaff
Found that there was equal amounts of AT and GC
Franklin and Wilkins
Used X Ray diffraction to find the 3D shape of DNA
Watson and Crick
Built a 3D model of the model of DNA and discovered the double helix shape
Clone
A genetically identical cell
Mitosis
Allows cells to grow and replaces warn out cells and repairs damaged tissue
In mitosis a parent cell divides to form
2 genetically identical daughter cells
Chromotids
The original chromosome and the copy of it
Gregor Mendel
Father of genetics
Monohybrid case
Only one factor is considered
Alleles
Alternative forms of the same gene
homozygous dominant
AA
homozygous recessive
aa
Heterozygous
Aa
Fertilisation
When the sperm and egg fuse in the oviduct
Use of amniotic fluid
Cushions and protects embryo
What is passed through umbilical cord
Glucose, oxygen
How the placenta is adapted
Villi provide a large surface area for diffusion, good blood supply ensuring diffusion gradient, short distance between mothers blood and baby's blood
Superovulation
Multiple eggs are released
Mutation
Random change to the structure or number of chromosomes
Genetic screening
Involves testing for the presence of a particular genetic condition or allele
genetic engineering
Changing the DNA of living organisms, commonly bacteria as it is easily manipulated and multiplies easily
Biodiversity
Variety of living organisms
Variation
Any difference between individuals of the same species
Types of Variation
Continuous, discontinuous
Continuous variation
Where there is a gradual transition e.g. Heights
Charles Darwin
discovered natural selection
Three main components of the circulatory system
Blood, blood vessels, heart
Main function of circulatory system
Transport various substances e.g. Oxygen, glucose, vitamins. Protection from disease
Red blood cells
Carry oxygen around the body, large surface area, contains haemoglobin, no nucleus
white blood cells
Protect the body from disease
Phagocytes
Engulf and digest micro organisms ( phagocytosis)
Lymphocytes
Produce antibodies which clump together micro organisms therefore they cannot reproduce and spread, also are made visible in the blood to phagocytes
Function of hepatic portal vein
Carries blood from the digestive system to the liver
Function of coronary arteries
Brings oxygen to the heart
double circulation
When blood goes through the heart twice in one complete circuit
Louis Pasteur
Disproved spontaneous generation through swan neck flask experiment
Steralization
Raise temp very high to kill all bacteria
Pasteurization
Raise temp so most bacteria will be killed
Pathogen
An organism that causes disease
Types of pathogens
Bacteria, Viruses, Fungi
Renal artery
Contains urea, has oxygen and glucose
Renal vein
No urea, no oxygen but has glucose and co2
Hepatic artery
Has toxic waste products and oxygen and glucose
Hepatic vein
No toxins
Bodies defences / barriers
Nose, skin, eyes, blood, stomach
Antigens
Chemicals on the surfaces of pathogens, which cause lymphocytes to react
Lymphocytes produce
Antibodies and phagocytes
Vaccinations
Liquid containing dead or modified pathogens which are administered to the body, they contain antigens which stimulate an immune response
Edward Jenner
Discovered the small pox vaccine.
Antibiotics
Chemicals such as penicillin which are used against bacterial diseases to kill them or reduce their growth
Drug
Any chemical that affects the functions of the body
Binge drinking
The consumption of a large amount of alcohol over a short period of time
Note 
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