UNIT 3 DAY 5 - BLAME YOUR GENES Flashcards
1
Q
What is DNA made up of what?
A
- ladderlike structure, rung of ladders are nitrogenous bases that come in 4 types: A,T,G,C
2
Q
Transcription
A
- sequence of ATGC bases in a molecule of DNA that is used as a template to form a molecule of mRNA, which has a complementary series of bases
3
Q
Translation
A
- sequence of bases in the molecule of mRNA is used as a template, within the ribosome, to assemble a string of amino acids into proteins
- shape of the resulting protein, which determines its function within the cell, depends on the sequence of amino acids that form it, which depends ultimately on the original sequence of bases in the DNA
4
Q
proteins
A
go on to form part of the cell or act as enzymes that build other parts of the cell
5
Q
Why are evolutionary biologists the ones to eliminate genetic diseases?
A
- wouldn’t selection eliminate disease –> causing genes?
- but some genes are so rare that natural selection can’t eliminate them, some common genes selected for even though they cause disease
- random mutations still happen
- natural selection limited because it is no match for mutations
6
Q
why do common genetic defects need a different explanation than rare genetic defects?
A
- common/ dominant mutations more easily eliminated by natural selection
7
Q
understand why the existence of dominant, fatal disease-causing alleles in populations requires a different kind of explanation. What is the explanation for the persistence of Huntingdon’s disease in human populations -
A
- if you have at least 1 copy of dominant gene that causes disease, you will get the disease and so will your children
8
Q
CFTR protein
A
- mutations in the CFTR gene that alters critical amino acids in protein, ultimately responsible for cystic fibrosis
- replacing one critical amino acid with another, changes shape and because its shape is so important, rendering it will make it unable to form the function
9
Q
cystic fibrosis
A
- build up of thick mucus, leads to persistent lung infections, destruction of pancreas, complications in other organs
- recessive genetic disease
10
Q
sickle cell anemia (heterozygous advantage)
A
- caused by single base change
- homozygotes for sickle cell allele have moon-shaped RBC
- blocks flow of blood and delivery of oxygen to tissues
- malarial parasites invade, divide and destroys cells
- environments with increased malarial prevalence likely to select sickle cell because advantageous
- caused by specific mutation in (B-goblin gene) that changes from an A to a T and changes amino acids that it is coded for
11
Q
How often do mutations arise?
A
mutations occur extremely often
12
Q
What is mendelian genetics?
A
- Mendel proposed that traits are built by hereditary particles called Genes
-Mendel’s genes are transmitted unchanged through the generations
This enduring nature of genes explains why a trait can reappear to blend in he first place - Mendel proposed that individuals carry not one but two copies of each gene, called Alleles
13
Q
genes
A
- stretches of DNA that codes for a protein and are grouped together in chromosomes in the nucleus of the cell
14
Q
alleles
A
- an individual inherits one set of chromosomes from her mother and one set from her father, giving them 2 copies (2 alleles) of each gene (diploid)
15
Q
dominant
A
an allele that is always expressed
