B1.2- What happens in cells? Flashcards
How does temperature affect enzyme controlled reactions?
As the temperature goes up the rate of reaction goes up until the enzymes denature (this is when the active site changes shape) the substrate can no longer bind to the enzyme and the rate of reaction decreases. This is an irreversible reaction.
How does ph affect enzymes?
Each enzyme has an optimum ph. A change in the ph affects the interactions between enzymes and may make them unfold which may change the shape of the active site
How does enzyme concentration affect rate of reaction?
The higher the enzyme concentration the higher the rate of reaction until all the substrate is used up, then the reaction will stop
Why does transcription happen?
DNA is too big to fit through the nucleus so mRNA is is made. It’s like a single strand of DNA. Transcription occurs when the double helix unzips. The DNA acts as a template and complimentary bad pairing happens except there’s no thymine and there is uracil instead.
How does substrate concentration affect enzyme controlled reactions?
The higher the substrate concentration the higher the rate of reactions until all the substrate is binded to an enzyme. This is the point of reaction and the rate of reaction remains constant
What is translation?
Proteins are made through translation this is when the mRNA attaches to a ribosome (in the mitochondria). Here the nucleotide sequence is interpreted in codons (3 amino acids) this forms a protein.
How do bases pair?
Through complimentary base pairing A=C T=G (adenine cytosine thymine and guanine). The double helix is joined by complimentary base pairing.
What do enzymes look like?
Enzymes are made up of long chains of amino acids, these are folded together to form a specific shape. This is called the active site
Do enzymes bind to all molecules?
Enzymes are highly specific. This means they can only bind to one type of substrate molecule. The substrate must fit exactly into the active site. This is called the lock and key hypothesis
What factors affect enzymes?
Enzyme concentration, substrate concentration, ph and temperature
What are enzymes?
Enzymes are biological catalysts made up of protein which speed up a reaction without being used up themselves
What is the structure of dna?
Dna is a double helix which are joined together by bases. Dna is made up of lots of monomers called nucleotides. Each nucleotide is made up a base (rectangle) a phosphate (circle) and a sugar (pentagon)
