Genetics and DNA Flashcards
(26 cards)
What is DNA?
the hereditary material in all organisms that is passed down from generation to generation
What are the base pairs?
Adenine and Thymine (A+T), Guanine and Cytosine (G+C)
What is a nucleotide?
a part of one half of the ladder of DNA; contains phosphate backbone, deoxyribose sugar, and the nitrogen-containing base
Chromosome
long strands of DNA molecules that are packaged into thickly coiled structures
Gene
a specific section of DNA that codes for one type of protein
Who were the early scientists that were involved in discovering DNA’s structure?
Rosalind Franklin, Watson and Crick
What is the shape of DNA?
double helix
Where is DNA located?
the nucleus of the cell
How does DNA replicate?
The strand splits in half, and each strand gets paired up with a new complementary strand to create two new strands of DNA.
What is complementarity?
A is complementary to T, G is complementary to C. Base pairs are complementary to each other.
What are the 4 main phases of the cell cycle?
G1, S, G2, Mitosis
What is mitosis?
the process of cell division
What are the 4 main phases of mitosis?
Prophase, Metaphase, Anaphase, Telophase
What happens in prophase?
chromosomes and mitotic spindle form
What happens in metaphase?
chromosomes line up
What happens in anaphase?
chromosomes are pulled apart by the mitotic spindle
What happens in telophase?
cell starts to separate into two new cells
What is cytokinesis?
when the cytoplasm divides
What is the purpose of checkpoints in the cell cycle?
to make sure that the cells are developing properly and that there is nothing wrong so that if there is a bad cancer cell it is stopped before it can reproduce
What is interphase?
the period of time in the cell cycle when the cell is not dividing
What is an allele?
one gene of the homologous chromosome pair that matches up with another gene from the opposite parent
What are dominant and recessive traits?
Dominant - one to show up in phenotype
Recessive - 2 to show up in phenotype
What does it mean if you are homozygous or heterozygous?
If you are heterozygous, you have one dominant allele and one recessive allele. If you are homozygous, you have two dominant or two recessive alleles.
What is a pedigree chart?
A pedigree chart is a way to figure out people’s genotypes
