B3 Flashcards
What do plant cells have the animal cells don’t?
Chloroplasts, cell wall and a vacuole.
What does the nucleus contain?
DNA in the form of chromosomes.
What does a cell membrane do?
Keeps cell together and controls what goes in and out.
What happens in the ribosome?
Proteins are synthesised.
What happens in the cytoplasm?
Chemical reactions.
What happens in the mitochondria?
The reactions involved with respiration take place.
What happens in the chloroplasts?
Photosynthesis.
What does the cell wall do?
Supports the cell.
What does the vacuole contain?
Cell sap.
What do bacteria have instead of a nucleus?
A single circular strand of DNA that floats freely in the cytoplasm.
What are chromosomes?
Long molecules of coiled up DNA.
What is the structure of DNA?
A double helix.
What are the short sections of DNA called?
Genes.
What connects the two strands of DNA together?
Bases.
What are the four different bases?
A, C, G and T.
Which bases pair up with which?
A and T, C and G.
Who built the first DNA model and when?
Watson and Crick in 1953.
What does DNA control the production of?
Proteins in the cells.
What is a section of of DNA that codes for a protein called?
A gene.
What decides the order of amino acids in a protein?
The order of bases.
What codes for the amino acid?
A sequence of three bases.
How does the code get from the DNA to the ribosome?
The mRNA carry it.
Why do different cells have different functions?
Because they all make different proteins.
Why do cells only make certain proteins?
Only some of the full set of genes is used in a cell.