Lectures 4&5 Flashcards
What are the 2 base pairs?
How many base pairs in each human cell?
- A-T & G-C
- 3 billion
How do genes and traits affect one another?
- Any trait can be affected by more than one gene.
- One gene can affect more than one trait.
How many chromosomes?
What are the sex chromosomes for male and female?
- 2 sets of 23
- Male-XY, Female- XX
What is mutation?
Any inherited alteration of genetic material.
Chromosomal disorders are the leading cause of what?
Intellectual disability and miscarriage.
What is aneuploidy and how does it occur?
Abnormal number of chromosomes, due to translocation or non-disjunction.
What is non-disjunction?
Chromosomes not separating properly during meoisis.
What is aneuploidy?
A somatic cell that does not contain a multiple of 23 chromosomes.
What is trisomy?
A cell containing three copies of one chromosome.
What is monosomy?
The presence of only one copy of any chromosome.
What is an example of autosomal aneuploidy?
Down syndrome.
Trisomy 18 is also known as what?
Edwards syndrome.
Trisomy 13 is also known as what?
Patau syndrome.
Does Turner syndrome affect males or females?
Females.
Does kleinfelter syndrome affect males or females?
Males.
List and describe the 2 abnormalities of chromosomal structure.
- Deletion, the chromosome breaks in two places and a segment is missing when the break is repaired.
- Duplication, adjacent, tandem or reverse depending on orientation.
What is translocation?
Two chromosomes break at different points, the deleted section from one chromosome attaches to the other chromosome.
List and describe the 2 ways in which the abnormalities of the chromosomal structure occur.
Insertion- The region deleted from one chromosome may end up as an insertion into another.
Inversion- A broken part of the chromosome is reattached to the same chromosome, but in the reversed order.
How do mutations occur, and which form of mutation is inherited and which is not?
- Mutations result from changes in DNA sequence.
- Germ line is inherited, Somatic is not.
List the 3 “Point mutations”
- Silent
- Nonsense
- Missense
List the seven effects of mutation.
- Lethal
- Conditional
- Loss of function
- Gain of function
- Null
- Suppressor
- Silent
What is genotype?
The genetic makeup of an organism.
What is phenotype?
The observable appearance of the genetics of an organism.
What are the 5 modes of inheritance?
- Autosomal recessive
- Autosomal dominant
- X-linked dominant
- X-linked recessive
- Y-linked
