Lecture 1: Introduction to Biodiversity Flashcards
LUCA
Last universal common ancestor
Hypothesis about LUCA
- LUCA existed about 4 billion years ago
- LUCA is the last common ancestor of all cellular life which exist on Earth today
- After billions of years of evolution, LUCA diverged into the different forms of life through natural selection
What we see today is the __ of evolution up until now
result
Three domains of Life
Bacteria, Archaea, Eukarya
A lot of____ still exist while categorizing organisms into similar groups
Uncertainty
Horizontal Gene Transfer
Horizontal gene transfer or lateral gene transfer is the movement of genetic material between organisms other than by the transmission of DNA from parent to offspring. HGT is an important factor in the evolution of many organisms.
The branches of the ‘Tree of life’ may be ___
interconnected
Organisms adapted to various habitats on Earth via evolution meaning
There is no single, correct answer for any habitat
Huge ___ within the same type of survival mechanism
diversity
Why study the diversity of life?
- Humans are inherently interested in our environment
- Humans are inherently interested in ourselves
- We learn about ourselves through studying other organisms
- We learn about Earth through studying life
Taxonomy
study organisms, name them, and put them into similar groups
Phylogeny
deduce evolutionary relationship between organisms put similar groups
Why is naming important?
Naming is important for us to communicate unambiguously
Conservation ecology
- Organisms are constantly interacting with the environment and one another
- Cannot intervene with the system without knowing these interactions
Predator and prey, and example
- Change in population sizes of predator
and prey are known to synchronize - Snowshoe hare (prey) and Canadian lynx (predator)
Woodland Caribou and Commercial Foresting
Woodland Caribous can not sustain population in areas such as Ontario and Quebec when the old forest is too disrupted.
Some organisms thrive by __ on their host, many infect human
parasitizing
Examples of parasitic organisms
Mycobacterium tuberculosis
Human Immunodeficiency Virus (HIV)
Staphylococcus aureus
Monkeypox virus
Epidemic
significant rise in occurrence of a disease, above the rate which is normally expected in a local population
Pandemic
Global epidemic, usually on more than one continent
Name of Covid-19 virus
SARS-CoV-2 is the name of the virus, standing for Severe Acute Respiratory Syndrome Coronavirus 2.
Why was the virus given the corona name?
Spike protein sticks out of the envelope making the virus look like a ‘sun’ (corona)
How many variants of corona-virus are known?
Seven different human-host coronavirus are known to date including SARS-CoV-2.
How many are nonthreatening?
Four are not as problematic (causes ~15% of the common cold) and have been recognized as early as 1960’s
SARS-CoV-1
- Severe Acute Respiratory Syndrome Coronavirus 1
- causative agent of 2002–2004 SARS epidemic
- about 8000 documented cases (0.08 million) across 29 countries
- 10% fatality rate
MERS-CoV
- Middle East Respiratory Syndrome Coronavirus
- first reported in 2012, and have caused multiple outbreaks since then
- about 2500 cases (0.025 million) documented until July 2022 accross ~30 countries
- up to 35% fatality late
SARS-CoV-2
- Causative agent of COVID-19
- about 612 million cases as of September 2022, globally
- 6.5 million deaths, about 1 % fatality rate
- tremendous damage to human society
Prior to COVID-19, we already had:
- Recognized, identified and studied multiple coronaviruses
- Encountered epidemic(s) caused by more deadlier versions of coronavirus
- Experience combatting this infection
- …in addition to knowledge on other viruses, vaccination, epidemiology, etc.
