Cell Biology Flashcards
What is the cell wall made from in plant cells?
Cellulose
Features of a plant cell that an animal cell doesn’t have?
Cell wall, vacuole, chloroplasts
What is the function of the nucleus?
Controls the activities of the cell
Which type of cell contains a plasmid?
Bacterial
Which cells have a cell wall?
Plant, bacterial and fungal cells
Definition of optimum?
The temperature/pH at which the enzyme is most active
What are enzymes and what do they do?
Enzymes are biological catalysts
They speed up reaction rates and remain unchanged
What are enzymes made of?
Proteins
What is a degradation reaction?
The breakdown of large substrates into smaller products
What are proteins made of?
Amino Acids
Examples of proteins?
Enzymes, hormones, antibodies, structural proteins etc
Is diffusion a passive or active process?
Passive
What diffuses into the cell? What diffuses out?
In- oxygen and glucose
Out- carbon dioxide
What is a concentration gradient?
The difference in concentration of a substance between 2 areas
What can pass through the cell membrane? What can’t?
Can- oxygen, carbon dioxide, urea, ethanol and water
Can’t- glucose
Where does aerobic respiration occur?
Mitochondria
Where does fermentation occur?
The Cytoplasm
Definition of osmosis?
The diffusion of water across a selectively permeable membrane
What is diffusion ?
Diffusion is the movement of molecules down a concentration gradient
What is active transport?
It is when molecules move against the concentration gradient
What does DNA code for?
Proteins
What shape is DNA? What is it held by?
Double helix
Held by complementary base pairs
What are the names of the 4 bases?
Adenine, Thymine and Cytosine, Guanine
What bases are paired together?
Adenine + Thymine
Cytosine + Guanine
What is messenger RNA? (mRNA)
It is a molecule which carries a complementary of the genetic code from the DNA to the ribosome
What happens if you place a plant cell in a strong salt solution?
The cell will lose water and become plasmolysed
What is the function of the ribosomes and mitochondria?
Ribosomes: sure of protein synthesis
Mitochondria: site of aerobic respiration
Definition of denature?
When the enzymes active site changes shape
What causes an enzyme to denature?
When the enzyme is exposed to extreme temperature or pH
What is a synthesis reaction?
Builds up smaller substrate molecules into larger molecules
What is the cell membrane made of?
The phospholipid bilayer and proteins
What cellular activities require ATP?
Muscle cell contraction, Cell division, Protein synthesis, Transmission of nerve impulses
How many ATP are produced in fermentation?
2 ATP
What happens if you put an animal cell in pure water?
It will gain water and burst
What happens if you place a plant cell in pure water?
It will gain water and become turgid
Function of the cytoplasm?
Site of chemical reactions
What does base sequence determine?
The amino acid sequence in proteins
