Genetics Flashcards
What are the symptoms of sickle cell?
Cold
dehydration
infections
Jaundice
stroke
leg ulcers
eyes, kidneys
What does a circle on a pedigree mean?
Female
What does a square on a pedigree mean?
Male
What is the centromere?
Holds
What are telomeres?
Both ends of the chromatids
Which must be protected from unnecessary repair and degradation
Where are heterochromatin typically found?
Centromeres and telomeres
What is heterochromatin?
Loped around histones and are inactive
What is a phenotype?
Outward, physical manifestation of organism
What is a genotype?
Full hereditary information of organism (even if not
expressed)
A folded protein has only 1 type of secondary structure.
True or False
False a protein can have both alpha helix and beta pleated alongside beta turns
What is a nucleotide?
Each nucleotide contains
Sugar
Base
Phosphate group
What is the major groove?
Where proteins are fit onto like restriction enzymes or transcription factors binds to
What is a minor groove?
Too small for proteins to bind to.
Describe structure of dna.
Double helix
Major and minor group
Equidistant
3 prime to 5 prime
How many H bonds does GC have?
3
What is a phosphodiester link?
How big is the nucleus?
5 to 10 um
What does the nucleolus do?
Site of transcription
Assembly of rRNA
What is the p arm?
Short arm of chromosomes
What does a chromosome has?
A p and q arm with a centromere and 2 sister chromatids
How is dna organised?
- Nucleotides make base pairs
-DNA wraps around histones to form nucleusomes - DNA coils
-DNA coils more and loops - DNA super coils
Why is DNA highly packaged?
So it fits in the nucleus and can be regulated orderly
How many hydrogen bonds does an A T bond have?
2
What are the types of chromatin?
Euchromatin
Heterochromatin
What is heterochromatin?
Condensed form of DNA
Transcription factors is the only form of gene regulation. True or false
False
Nucleosomes can be modified
How can we make chromatic more accessible?
Histones can be enzymatically modified
Histones can be displaced by chromatin
remodeling complexes
What does semi conservative mean?
one-half of each new molecule of DNA is old; one-half new.
What direction is DNA replicated in?
5’ to 3’
Movement of DNA polymerase
All of our genes code for proteins. True or false
False
Only 2 percent
Lots of junk DNA
the rest code for regulation of genes
What are exons?
Coding region
What are introns?
Non coding region
What is translation region?
mRNA has only exons
True
What is a codon
Set of 3 bases which produce an amino acid
How many amino acids are there?
20
Single gene mutations cause big effects.
Single point mutation cause dysfunctional proteins
Why does sickle cell happen?
One hydrophilic amino acid is substituted for a hydrophobic one
This makes haemoglobin mor sticky and clumped together.
What is RNA splicing?
Removal of introns in rna
What is alternative splicing
When the introns are removed
The exons are rearranged which produces different proteins
What are reading frames?
A base is inserted or deleted causing all the genetic information afterwards to be scrambled as dna is read in 3s
How are extracellular enzymes controlled?
Typically through post translational modifications to prevent the enzymes from digesting the cell
What is the anticodon?
The base of 3 On the tRNA
