Define genetics
The study of heredity and variation in cells, individuals, and populations.
What are genes
They are a sequence of dna that carrier instructions for making a protein or RNA. They are the functional unit of heredity and variation.
Define molecular genetics
The study of the structure and function of genes at a molecular level
What are some reasons to study molecular genetics
- human health and disease
- forensics
- agriculture
- environment
- evolutionary biology
Define phenotype
the visible traits that are coded by a genotype. They also have environmental components. E.g eye color
Define alleles
variant forms of a gene caused by differences in DNA sequences
Define genome
all the genetic information of an organism (the entire DNA sequence)
What is a genotype
The specific genes inherited by an individual
What is gene expression
to turn on a gene and turn it from a genotype into a phenotype, it follows the central dogma of biology
What is protein expression
The type and abundance of proteins in the cell.
what is the difference between structural proteins and signaling proteins
structural proteins - maintenance of cell shape
signaling proteins - hormones and receptors
What causes phenotypic variation?
different alleles, different regulation and expression of those alleles
Does similar alleles and similar gene regulation lead to more similar protein expression and phenotype (within immediate family and relatives)
Yes
What is a trait
any characteristic of an individual that is heritable
Who was gregor mendel
he was a monk in 1865 that studied inheritence through peas, he tracked the changes in flower colour along with other characteristics in thousands of pea plants, he describe that heritable result from a mixing of “particulate factors” and that every organism as two copies of particulate factors one that came from each parent.
What modern concept fit mendel’s discription of particulate factors
chromosomes
What happens to homologus chromosomes
they separate during meiosis (cell division) to produce 4 daughter cells, each with 1/2 the number of chromosomes.
what is a gamete and how may sets of chromosomes does it have
A gamete is a reproductive cell, they have half the number of chromosomes, aka 23, aka n
What is a zygote, how many chromosomes
it is the first cell that is produced, it is a random combination of chromosomes from the parents, 2n aka 46
What are the two components of chromosomes
proteins and dna
what are the three experiments that established dna as the heriddy molecule
griffith’s experiment, avery et al, and hershy and chase
explain griffith’s experiment
griffith noticed that when he heat killed the s-strain of pnemonia bacteria and mixed it with the r-strain and then placed it in a rat, it caused the viral effect, which means that a tranforming agent was released caused the r-cells to transform into the s-cells.
Explain what avery et al did
they all further explored griffith’s experiment by using the same strain mixture and mixing in different enzymes that would break down one out of teh three competidors for heriditory molecule, included rna lase, dna lase, and peptide lase. The one that broke down dna showed that the rat survived.
describe hershy and chase’s experiment
they used their knowledge of the bacteriophage cycle, they grew the virus in an isotope of phosphate and sulfur, this then created a way for the scientist to identify and track the molecules. This was based on the knowledge that phosphate is present in dna and that sulfur is present in proteins. Then they saw that the progeny generation had the phosphate in the original virus, this was the nail in the coffin and proved that dna was the heridity molecule.
