Test 7: Genetics Flashcards
What is DNA?
DNA is the hereditary blueprint for all biological traits and processes. It is the original copy of a gene.
What structure is DNA?
Double helix structure.
What is chromatin?
It is the mass of DNA in a nondividing cell.
What happens when the cell divides?
Chromatin DNA contracts itself into compact “sticks” called chromosomes.
What is a karyotype?
It is the representation of a complete set of chromosomes.
How many chromosomes do humans have?
We have 46 chromosomes or 23 pairs of homologous chromosomes (one set from each parent).
What does DNA contain?
- Sugars, phosphate groups (sugar phosphate backbone)
- Nitrogen bases (A, T, G, C)
Where do we find DNA?
In the nucleus.
What is mRNA?
A duplicate copy of a gene.
Where do we find mRNA?
In the nucleus and cytoplasm.
What structure is mRNA?
Single strand structure.
What are the mRNA bases?
A-U G-C
Where do we find tRNA?
In the cytoplasm.
What are the tRNA bases?
A-U G-C, tRNA carried bases in triplets.
What structure is tRNA?
Clover shaped.
What is a gene?
It is a segment of DNA.
What do genes do?
- Provide the instructions for making proteins.
- Will code for a series of amino acids which will make a functional protein.
Why is the genetic code said to be a triplet code?
Because a series of 3 nitrogen bases comprised of some combination of A, T, G or C, will code for a particular amino acid.
What’s a genome?
It is a complete set of genes. The A-T-G-C sequence for all genetic information.
What do eukaryotic cells contain?
They contain a membrane bound nucleus which contains DNA.
How many proteins does the human body contain?
30 000 - 50 000
Give examples of specific roles proteins play in the body.
- Hormones
- Antibodies
- Enzymes
- Hemoglobin
What do proteins determine?
Proteins determine the character traits of an organism.
What are the building blocks of proteins?
Amino acids.
