Genetics - basic principles
Study these flashcardsFree · spaced repetition · iPhone, Android, Mac & web
All cards
1
What did Mendel do?
Experimental experiment
Breeding peas
Only looked at simple > complex traits
Breeding peas
Only looked at simple > complex traits
2
Outline Mendel's law of segregation
Pairs of alleles in parents segregate into gametes
Offspring receive one allele from each parent
Offspring receive one allele from each parent
3
Outline Mendel's law of independent assortment
Alleles for different traits are inherited independently of each other
4
Outline Mendel's law of dominance
Where there are different alleles for a trait, dominant allele determines phenotype
5
Outline what is meant by complex traits
Influenced by many genes and environmental factors
Multifactorial
Eg. height, weight, skin colour
Multifactorial
Eg. height, weight, skin colour
6
Define phenotype
Genetic + environmental effects
7
Define heritability
Measure of current variance in a trait in a population that can be accounted for by the genetic variation within the population
8
Equation for all heritability
9
Equation for additive heritability only
10
Equation for estimating heritability in twin studies
11
Describe what this means:
Heritability of height estimated to be 80%
Heritability of height estimated to be 80%
Means variation in height is 80% explained by genetics
12
Define genotype
Genetic make-up of an individual
13
Define mendelian trait
Controlled by a single locus (eg. single base pair substitution)
14
Big genomes = more complex
True or false?
True or false?
Sometimes
Not always the case
Bigger genomes contain less protein coding sequence
Not always the case
Bigger genomes contain less protein coding sequence
15
Define redundancy in terms of DNA
More than 1 codon can code for the same aa
16
Outline the central dogma
Information only flows 1 way
From genes to proteins
From genes to proteins
17
Outline somatic mutations
Occur in nongermline tissues
Cannot be inerited
Cannot be inerited
18
Outline germline mutations
Present in egg/sperm
Can be inherited
Can cause cancer family syndrome
Can be inherited
Can cause cancer family syndrome
19
Outline the 3 types of point mutations
Silent
Nonsense
Missense
Nonsense
Missense
20
Image occlusion: name the hidden labels
21
Image occlusion: name the hidden labels
22
Image occlusion: name the hidden labels
23
Define indel
Insertion/deletion mutation
24
Define haplotype
Genetic variants inherited together
Physical grouping of genomic variants (or polymorphisms) that tend to be inherited together
Reflects a unique combination of variants that reside near each other on a chromosome || notes:https://www.genome.gov/ genetics-glossary/haplotype
Physical grouping of genomic variants (or polymorphisms) that tend to be inherited together
Reflects a unique combination of variants that reside near each other on a chromosome || notes:https://www.genome.gov/ genetics-glossary/haplotype
25
Other than mutation, name one thing that can increase genetic diveristy
Crossing over and recombination
26
Image occlusion: name the hidden labels
27
Image occlusion: name the hidden labels
28
Image occlusion: name the hidden labels
29
Image occlusion: name the hidden labels
30
Image occlusion: name the hidden labels
31
Image occlusion: name the hidden labels
32
Image occlusion: name the hidden labels
33
Repetitive elements
(which are common in the
genome) are associated
with replication errors.
Replication slippage can
lead to deletions and
insertions. Short tandem
repeats (microsatellites)
Growing strand
3' 5' Template strand
Temporal dissociation
GTC
are especially prone to
this error.
5'
Sætre & Ravinet, 2019
GTC
Insertion in
growing strand
GTC GTC 3'
5'
3'
Misaligned re-annealing
Deletion in
growing strand
5'
38
(which are common in the
genome) are associated
with replication errors.
Replication slippage can
lead to deletions and
insertions. Short tandem
repeats (microsatellites)
Growing strand
3' 5' Template strand
Temporal dissociation
GTC
are especially prone to
this error.
5'
Sætre & Ravinet, 2019
GTC
Insertion in
growing strand
GTC GTC 3'
5'
3'
Misaligned re-annealing
Deletion in
growing strand
5'
38