B3 Whole Flashcards
Briefly describe chromosome and how it links to gene and Dna
Chromosome have genes
Gene is short length of chromosome
Chromosome long length of dna
DNA coiled to form chromosome
How did Watson and crick make first model of dna
They used data from others e.g xrays to know dna has double helix
Strands of dna made of …..
Nucleotides
Dna has 4 bases when A-T and G-C pair it’s Called
Complimentary pairing
How does Dna copy
First the DNA copies itself when cell divides so cell has DNA
Then double helix unzips forming 2 single strands
New nucleotides join using complimentary pairing
Where does respiration happen and where is ribosomes found
Mitrohondria
Cytoplasm
Proteins how are they made
Long chained amino acids joined
Protein functions
Structural P used for build up cells
Collagen and hormones carry messages
Insulin controls blood levels
What’s a enzyme
Biological catalyst speeds up reaction
How does enzyme work
Enzyme has a active spot ( part where subtrates join) enzymes need substarte to be correct shape to fit in active spot. This is called LOCK AND KEY
Conditions for enzymes to work
Needs constant temperature to work at optimium
If ph high or low enzyme denatures
Low temp makes molecule move slow so less Chance subtrates less likely to collide to enzyme
What does respiration do and where is it trapped
Provides energy from food
Trapped in ATp This provides energy for other processs in our body
Aerobic respiration is with O2
C6H1206 + 06 = 6CO2 + 6H2O
Word equation of anaerobic respiration
Glucose = lactic acid + energy
Briefly explain process of mitosis
When cell divides it copies dna. Dna copied and forms x shaped chromosome
Chromosome line up in middle of cell cell fibers then pull them apart chromosomes then go to opposite end of cells
Memberanes from around chromosome
Cytoplasm splits
What is mitosis
Makes new cells for growth and repair its wen a cell reproduces itself to produce 2 identical offspring
What is meisos
Produces cells that have half number of chromosome only happens in ovaries and testses
Process of meisos briefly
When a cell divides DNA copies to form 2 chromosomes
Chromosome line up in middle pairs then are pulled apart so new cell has copy of cromsome
Cell divides again making chromosomes in the centre of cell again and they are pulled apart
You have 4 gametes
What does the Heart have to pump blood around body
Has 4 chambers right atrium and ventricle, left atrium and ventricle
How does heart pump blood around body
Blood flows in both Atrias from vein
Ventricles pump blood in arteries
Semilunar, triscupid and biscupid prevent back flow of blood
Pulomanary vein and vena cava carry blood to heart
Aorta and pulomanry arteries carry blood away from heart
What do red blood cells do
Carry 02 around body have nucleus to carry more O2 and larger surface area to be more quicker
What does haemoglobin do
Combines with O2 to make oxyhaemoglobin this is reversible and oxygen is released from oxyhaemoglobin in tissues
What do arteries do and features of arteries
Carries blood away form heart it has thick and elastic wall to resist high pressure
Veins and features
Carry blood to heart has large lumen to make blood flowing due to low pressure
capillaries and features
Allows materials to pass through blood has permeable wall so things can diffuse
Bad thing about selective breeding
Causes inbreeding and causes health problems
Genetic engineering process
desired characteristics chosen
Useful gene is cut from organism chromosome
Enzymes cut other organisms chromosome and then they insert useful gene
Pros and cons of GM crops and what’s the process called wen u change persons gene
Increase in yield
people don’t think it’s safe
Gene therapy
Process of cloning nuclear transfer
Remove nucleus from unfertilised egg cell
Complete set of chromosomes inserted to empty egg from adult body cell
Egg is stimulated by electric shock making cell divide
Then that egg is implanted in Surreygate mum
How does tissue culture work work to clone plants
Few plants put in growth medium with hormones they grow to new plants
Why are plants easier to clone that animals
Because plant calls can differentiate and animal can’t
