Cell Structure
What structure controls the activities of the cell?
Nucleus
cell membrane
The small units from which proteins are assembled.
Amino acids
What describes the transfer of genetic information from one cell to another.
Genetic engineering
Name the four bases found in DNA.
Adenine, thymine, cytosine and guanine
Where do chemical reactions take place in the cell?
Cytoplasm
diffusion
These proteins speed up cellular reactions without being used up.
Enzymes/biological catalysts
This small circular piece of bacterial DNA can carry a required gene.
Plasmid
State the complementary base-pairing rules in DNA.
A pairs with T; C pairs with G.
Ribosome
What word describes the movement of water from a higher water concentration to a lower water concentration through a selectively permeable membrane?
Osmosis
The molecule on which an enzyme acts.
Substrate
A bacterial cell containing a gene from another organism is described using these two words.
Genetically modified
A section of DNA that codes for a protein.
A gene
What organelle releases energy during aerobic respiration?
Mitochondrion
This process uses energy to move substances against a concentration gradient.
Active transport
Why does an enzyme normally act on only one particular substrate?
Its active site is complementary to that specific substrate.
Give an example of genetic engineering?
This molecule carries a complementary copy of the genetic code from the nucleus to a ribosome.
Messenger RNA (mRNA)
Name two structures found in a bacterial cell but not a typica animal cell
cell wall and plasmid
What happens to a plant cell placed in a solution with a lower water concentration than the cell?
Water leaves by osmosis and the cell becomes plasmolysed.
Explain why a high temperature can stop an enzyme working.
The enzyme becomes denatured, changing the active site’s shape so the substrate no longer fits.
Put these stages in order: insert plasmid into bacterium; extract gene; extract plasmid; insert gene into plasmid.
Extract gene → extract plasmid → insert gene into plasmid → insert plasmid into bacterium.
How does the base sequence of DNA determine which protein is produced?
determine which protein is produced?The base sequence determines the sequence of amino acids in the protein.