BIOLOGY - Unit 1 ( DNA and Cell Structure )
Describe the structure of chromosomes
1. Composed of DNA 2. The two strands of DNA are held together by complementary base pairs 2. A,T,C,G
Describe the ultrastructure of a bacteria cell
A bacteria cell has a Cytoplasm, a Plasmid, a Cell Wall, a Cell Membrane, Ribosomes, Genetic Material and a Flagellum
Describe the ultrastructure of a fungal cell
A fungal cell has a Cytoplasm, a Cell Wall, Mitochondria, a Nucleus, a Cell Membrane, Ribosomes and Vacuous
Describe the ultrastructure of a plant cell
A plant cell has a Nucleus, a Cell Membrane, a Cytoplasm, Ribosomes, Mitochondria, a Cell Wall, Vacuoles and Chloroplasts
What is the difference between a plant cell wall and a bacteria and fungi cell walls
A plant cell walls main component is cellulose, whereas bacteria and fungi cell walls do not contain cellulose and instead use other chemicals.
What advantage does cellulose walls have against other cell walls
Cellulose gives plant cells a very strong structures so therefore the walls in bacteria and fungi are not as strong
How does DNA determine the characteristics of an organism
1. The order of bases determines the sequence of amino acids in proteins 2. This determines the type of protein produced and it's function 3. The proteins produced may be an enzyme or hormone
Describe the ultrastructure of an animal cell
An animal cell has a Nucleus, a Cell Membrane, a Cytoplasm, Ribosomes and Mitochondria
What is the function of the chloroplasts
Chloroplasts contain chlorophyll and are site of photosynthesis.
DNA
DNA
What does DNA contain
DNA contains the genetic information for making proteins
What is DNA
DNA is a code that contains the genetic information that determines the sequence of amino acids in proteins
What is the structure of DNA
DNA is a double stranded Helix held by complementary base pairs
What are genes
Genes are the sections of DNA that contain the coded genetic information for making proteins
What is genetic code made of
Genetic code is made up of complementary base pairs A = adenine T = thymine C = cytosine G = guanine
Where is DNA located?
In the nucleus of every cell
What is the function of the Mitochondria
The Mitochondria are the site of aerobic respiration ( where the ATP is produced)
What is the function of the Nucleus
The Nucleus controls cell actives and contains genetic material (DNA).
What is the function of the cell membrane
The cell membrane controls the movement of substances into and out of the cell
What is the function of the cell wall
The cell wall supports the cell, gives it a rigid structure and prevents the cell from bursting
What is the function of the cytoplasm
The cytoplasm is the site of many chemical reactions in the cell
What is the function of the plasmids
The plasmid holds genetic material (DNA) and is used for genetic engineering.
What is the function of the ribosomes
The ribosomes are the site of protein synthesis
What determines the sequence of amino acids that make up a protein
The sequence of DNA bases in a gene determines the sequence of amino acids that make up a protein.
How are the two strands of DNA held together
The two strands of DNA are held together by complementary base pairs ( A and T, G and C )
What is the function of the vacuole
The vacuole contains water, salt and sugars and support the cell.