key concepts in biology Prat 2 Flashcards
Describe the structure of a generalized animal cell. [4 marks]
Cell membrane, the movement of molecules into and from the cell
Cytoplasm — is made from water and where cellular reaction occur
nucleus — contains genetics material which controls the cells
ribosomes — Makes protein synthesis
Mitochondria — are the site of respiration
Describe the structure of a generalised plant cell. [4 marks]
Cell membrane - the movements of molecules into and from the cell
Cell Wall - provides support (made from cellulose)
Cytoplasm - where cellular reaction occur(is made from water)
mitochondria - the site of respiration
ribosomes - make protein synthesis
vacuole - stores cell sap
Nucleus - contains genetics material which controls the cell.
Chloroplasts - where photosynthesis occurs.
What conditions can denature an enzyme? [2 marks]
High temperature
extreme (very high or low) pH
Describe the structure of a prokaryotic cell. [4 marks]
It has no nucleus to contain the DNA, instead the DNA IS present in the cytoplasm.
Flagellum allows the to rotate or move like whips.
Cell wall provides protection.
The cytoplasm is made out of water and where reaction occurs
the membrane is the movements of molecules into and from the cell.
Describe the differences between light and electron microscopes. [3 marks]
Answer (three from):
light microscopes are lower magnification
they are also lower resolution
light microscopes can study living cells but electron microscopes cannot
electron microscopes are more expensive
transmission electron microscopes look at cross sections of samples
scanning electron microscopes look at samples in three dimensions
Describe the differences between light and electron microscopes. [3 marks]
Answer (three from):
light microscopes are lower magnification
they are also lower resolution
light microscopes can study living cells but electron microscopes cannot
electron microscopes are more expensive
transmission electron microscopes look at cross sections of samples
scanning electron microscopes look at samples in three dimensions
