Study Guides (390,000)
CA (150,000)
UTSC (10,000)
Midterm

BIOA01H3 Study Guide - Midterm Guide: Genotype Frequency, Allele Frequency, Microevolution


Department
Biological Sciences
Course Code
BIOA01H3
Professor
Mark Fitzpatrick
Study Guide
Midterm

This preview shows pages 1-3. to view the full 37 pages of the document.
BIOA01 Study Guide
Lec 02: Microevolution-Genetic Changes Within Populations
Event
Distance (m)
Time (Mya)
Formation of Earth
15
4500
First Evidence of
‘life’-Self
Replicating
13
3800
Oxygen producing
Cyanobacteria
9
2700
Significant Oxygen
in Atmosphere
8
2500
Multicellular
Organisms
2
600
Plants Move Onto
Land
1.55
465
Amphibians
Emerge From
Water
1.2
370
Trilobites
1.17
350
P-T Extinction
0.83
250
Age of Dinosaurs
0.8
240
Pangaea Breaks
0.67
200
K-PG extinction
0.22
66
Mammals
0.2
60
Hominins
0.01
3
Modern Humans
0.0007
0

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Evolution
Definition: changes in the genetic makeup of populations over time, sometimes resulting in
adaptation to the environment and the origin of new species
Biological evolution
Definition: changes in the genetic makeup of populations; individuals do not evolve on its own
● Change in allele frequencies in populations
● Genetic changes in populations
● Individuals

do not evolve
Penicillin
● Product of Penicillium

mould
● antibiotic drug that kills and/or inhibit the growth of bacteria
● comes from product of penicillium fungus
● Represents an evolved response to protect from the attack of bacteria
○ bacteria has evolved to resist antibiotics
"zone of inhibited growth”—> no bacterial growth
Microevolution
Definition: population level changes within a species
● heritable variation in genetics of a population
○ ex: red ladybug vs black ladybug (variation in colour)
● Natural selection
● Other evolutionary forces
Population
○ Individuals of species at same time and place
● Microevolution under strong natural selection
○ Example: antibiotic resistance
Macroevolution
Definition: changes between a species over time and breeding is not possible due to major
changes in the species
● ex: apes evolved into modern humans or chimpanzees
Phenotypic Variation
Definition: heritable traits in physical appearance and/or function
● Phenotypic plasticity
There are 2 categories of phenotypic variation:
1. Quantitative Variation
Definition: characteristics with a range of variation and can be quantified
● Characteristics with a range of variation
● Controlled by multiple genes

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

● Can be measured
     2.   Qualitative Variation
Definition: characteristics with distinct states
polymorphisms: distinct variants of character; ability to assume different forms or
shapes
○ ex: ladybug variation; black bug with 2 red spots or red bug with 2 black spots
Bell Curve Distribution
● some individuals are outliers but majority are in the middle
○ ex: height of population can be very tall, very short or average
■ if only taking the average of one gender’s height, the average height also
varies (male average height vs female average height)
Genes and Environment
● Genotypes and phenotypes are not completely correlated
● Only genetic differences in phenotype are heritable
phenotypic
variation

due to genetics and/or environmental factors
○ ex: hydrangeas of the same genotype but different environments have different
coloured petals due to the acidity of the soil
■ acidic soil produces blue flowers, basic soil produces pink flowers
● phenotypic variation is typically affected by genes AND environment
○ depends on how much is inherited and how much is due to environment
● Experiments to determine connection between phenotypes and genotypes
○ Keep genetics constant, vary environment
○ Breeding experiments, selection experiments
Experiment: Genetics and Activity in Mice
● 8 mice (4 experimental, 4 control)
○ experimental mice were bred based on most active mice
● 10 generations of breeding
Conclusion of experiment: genetic variation is the cause of level of activity in mice
Cause(s) of Genetic Variation
● mutation: allele is changed such that it alters the genetic makeup of the gene
○ as more mutations are introduced, new genes are too
● recombination: pieces of DNA from adjacent chromosomes combine together to form
new genes
Artificial Selection
Definition: breeding of plants and animals to produce desirable traits
Lecture 03: Hardy-Weinberg & the Agents of Evolution
You're Reading a Preview

Unlock to view full version