Bio1001 Exam

HIV

• Human Immunodeficiency Virus

• a virus that attacks the immune system

• can lead to AIDS if not treated

Zoonotic Disease

• a disease that humans acquired from another species (non human animal)

Spillover event

• a disease that jumps a species barrier

• more likely between species

SIV

• HIV genome was sequenced

• genetically similar to HIV but in non human primates

Viruses on tree of life

• non living

• don’t carry the 7 characteristics of a living organism

• only alive once attached to a host

Characteristics of Viruses

• acellular

• having genetic material (DNA or RNA) inside a protein shell (capsid)

• being obligate intracellular parasites (needing a host to replicate)

• acking cellular structures and metabolism

• being very small

• having specific host ranges

• evolving rapidly through mutation

AZT

• vaccine for HIV

• instead of grabbing a T, RT will grab AZT (similar shape)

• stops RT and no new bases are added

• a mutation in RT stops AZT from working (resistance)

Scientific Theories

• must be testable

• must be falsifiable

• is falsified, change theory

Core Theory of Evolution (4)

1. change in allele frequency

2. all life is related through a common ancestor

3. species change over generations

4. mutations are heritable and evolution is not predetermined or optimized for perfection

Lamarack

• change is driven by individuals (transformational)

Darwin

random mutation that generate new by natural selection (variation driven by external pressures)

Misconceptions about Evolution

• humans are directly descended from chimpanzees

• humans are the most evolved species

• mutations are directed to needs

• selection results in perfect species

Misconceptions Solved

• humans are RELATED to chimpanzees

• everything has been evolving for the same amount of time

• mutations are random

• selection favours those who are better adapted to the environment