B1.2

Descrição

DNA, genes and chromosomes. Rate of reaction. Enzymes Factors affecting enzyme reactions
Abbie  Gray
FlashCards por Abbie Gray , atualizado more than 1 year ago
Abbie  Gray
Criado por Abbie Gray mais de 4 anos atrás
2
0

Resumo de Recurso

Questão Responda
B1.2 What happens in cells DNA -it is genetic material that is a polymer. -it is found in the nucleus - a large and complex molecule
Description of DNA -made up of two strands that form a DOUBLE HELIX. -have complimentary base pair of A and T, C and G. -has strong covalent bonds and a sugar phosphate backbone. DNA also can create Chromosomes (which are thread made up of DNA.) Chromosomes are made up of genes.
Genes -these are small sections of DNA -they code for a specific sequence of amino acids to make a specific protein. -they can be copied and can be passed on to the next generation. Enzymes are BIOLOGICAL CATALYSTS that break substances down. E.g carbs, proteins and lipids. LOCK AND KEY. METHOD
Enzymes -each enzyme has a specific active sit so it can bond to a specific substrate or substrates. Factors affecting enzyme action. -low temperatures decrease the number of collisions and molecular movement. -high temperatures change the active site which causes it to denature.
. Amino acids. -amino acid chains can form enzymes -they have strong forces to hold it together and create its shape. High temperatures break the forces. Causing it to change shape.
Affects of pH -each enzyme works best at a certain pH. -e.g enzymes in digestive system work best at 7.0pH-7.4pH. -amino acids have charges and changing pH affects the charge. - cashing it’s shape to change Once the enzymes reaches its optimum pH. It becomes denatured and won’t break down substrates.
Substrate concentration. -enzymes work best when there are plenty of substrates available. Increased concentration= increased enzyme activity. Enzyme concentration. - Increased activity= more substrates broken down. Sometimes the substrates or enzymes can exceed the others amount. Therefore, the enzyme may run out of substrates to break down or have too many. This will slow the reaction.
Rate of reaction =amount of reactant used or product formed divided by time taken - the time it takes for a reaction to take place. -every reaction has different speeds. Increasing rate of reaction -temperature increased -Using a catalyst -solid pieces being made smaller - pressure of reacting gas increased -concentration increased.

Semelhante

Biology AQA 3.1.3 Cells
evie.daines
Biology AQA 3.2.5 Mitosis
evie.daines
Biology AQA 3.1.3 Osmosis and Diffusion
evie.daines
Biology- Genes, Chromosomes and DNA
Laura Perry
Biology- Genes and Variation
Laura Perry
Enzymes and Respiration
I Turner
GCSE AQA Biology - Unit 2
James Jolliffe
GCSE AQA Biology 1 Quiz
Lilac Potato
Using GoConqr to study science
Sarah Egan
Cells and the Immune System
Eleanor H
GCSE Biology AQA
isabellabeaumont