Topic one. Flashcards
What plant cells have that animal cells don’t.
Rigid cell wall
Large vacuole
Chloroplasts
Animals and plant cells.
What they have in common.
Nucleus
Cytoplasm
Cell membrane
Mitochondria
Nucleus.
Contains DNA that controls what the cell does.
Cytoplasm
Gel-like substance where most of the chemical reactions happen.
Cell membrane.
Holds the cell together and controls what goes in and out.
Mitochondria.
Where most of the reactions for respiration take place.
Respiration releases energy that the cell needs to work.
Rigid cell wall.
Made of cellulose, gives support to the cell.
Large vacuole.
Contains cell sap, a weak solution of sugar and salts
Chloroplasts.
Where photosynthesis occurs.
They contain a green substance called chlorophyll.
Do bacterial cells have a nucleus?
No.
What 4 features does a bacterial cell have?
Chromosomal DNA.
Plasmids.
Flagellum.
Cell wall.
Chromosomal DNA.
Controls the cells activities and replication.
It floats fee in the cytoplasm.
Plasmid.
Small loops of extra DNA that aren’t part of the chromosome.
Contain genes like for things like drug resistance and can be passed between bacteria.
Flagellum.
A long, hairlike structure that rotates to make the bacteria move.
Microscopes.
Let us see things we can’t see using the naked eye.
When were light microscopes invented and what did they let us see?
1590s.
Nuclei, chloroplasts and mitochondria.
When were electron microscopes invented and what did they let us see?
1930s
Smaller things in more detail like an internal structure of mitochondria and chloroplasts and even plasmids (much smaller).
What is the formula for magnification?
Magnification= length of image divided by length of specimen.
DNA molecule.
Two strands coiled together in the shape of a double helix.
The structure of DNA.
The two strands are held together by chemical bases.
What are the four bases.
A- adenine.
C- cytosine.
G- guanine.
T- thymine.
Base pairings.
A-T
C-G
What holds the base pairs together?
Weak hydrogen bonds.
On a sugar phosphate background.
What is a gene?
Is a section of DNA, and a sequence of bases in a gene code for a specific protein.
Franklin and Wilkins.
Worked out that DNA had a helical structure by directing beams of X-rays onto crystallised DNA and looking at the patterns the x rays formed as they bounced off.
Watson and Crick.
Used the ideas, along with the knowledge that the amount of A and G matched the amount of T and C to make a model of the DNA molecule where all the pieces fitted together.
DNA expirement
Explain
PS- What do cells make?
Proteins by stringing amino acids together in a particular order.
PS- what do three bases code for?
For a particular amino acid.
PS- what does TAT code for.
GCA.
