LAST MIN BIO

What gave eukaryotes the ability to arise?

endosymbiosis

when did the eukaryotes arise?

2,000 million years ago

what came first-- land plants or oxygenic photosynthesis?

Oxygenic photosynthesis--3,000 MYA. This gave way for plants to eventually move to land 480 million years ago

How did land plants arise

Archaeplastids (algae) absorbed chloryphll via endosymbiosis and land plants descended from an alga that colonized the terrestrial enviorment

Defining characteristic of Archaeplastids?

Endosymbiosis of chloroplasts

algae

represent majority of carbon production on the planet

Example Archaeplastid organisms?

Red algae

Green algae

Land plants

What color of algae is not an Archaeaplastid, and what class does it belong to?

Brown algae, Stramenopiles

Defining characteristic of Metamonads?

A cluster of 4 flagella

Metamonad organims example?

Giardia-- parasite

groups of metamonads live inside of termite guts

Metomonad endosymbiotically absorbed a bacteria that can digest wood, and termites endosymbiosis the metamonad enabling them to digest wood

Defining characteristics of Ameobazoans?

move using ameboid movement

similar crawling movement to cells in our immune system so they are a good model organisms

Defining characteristics of Opisthokonts?

Monophyletic group formed by animals and fungi-- distinguishing characteristic = movement by sperm like single posterior flagella

What is the SAR group composed of?

Stramenopiles

Alveolates

Rhizaria

What are Stramenopiles?

SAR group

synapomorphy= hairy flagella

Kelp, brown algae, oomocytes (parasite harmful to crops)

What are Alveolates?

SAR group

Synapomorphies: unicellular with flattened sacs, alveoli, that stiffen the membrane

Dinoflagellates which are important to coral reefs

and parasites that can cause malaria

What are Rhizaria

SAR Group

Live on the ocean floor

Floating on/near ocean surface

Terrestrial soil

no morphological synaomorphy

What is a Protist?

ANY Eukaryote other than--

Fungi

Land Plants

Animals

(not a monophyletic group)

What was the Great Oxidation Event

cyanobacteria devloped the ability to release oxygen as a biproduct of photosythnesis

When was the Great Oxidation Event?

2,400 million years ago

What was the End Permian extinction?

Largest extinction in history caused by Siberian Traps Volcanos

95% of the population died

Why did the End-Permian volcanic eruptions have such a devastating impact?

The eruptions released massive amounts of carbon dioxide which

rapidly warmed the ocean,

acidified the ocean,

decreased the amount of oxygen available in the ocean.

When did the End Permian extinction occur?

250 million years ago

Was the End Permian extinction before or after the Cretaceous- Paleogene, K-Pg extinction?

The end Permian extinction (250 mya) was way before the Cretaceous- Paleogene K-Pg extinction (66 mya).

What was the Cretaceous-Paleogene extinction event?

75% of species, dinosaurs eliminated.

caused by asteroid.

created many open niches for mammals to fill

When was the Cretaceous -Paleogene extinction?

66 mya

What was the effect of the Cretaceous-Paleogene extinction?

Adaptive radiation of mammals

When was the first evidence of life and what major event came next

3,800 million years ago (3.8 billion years ago)

Oxidative photosynthesis came next

Cretaceous sounds like crate, asteroids make craters = Cretaceous-Paleogene was the extinction of dinosaurs

.

Mamallian Adaptive radiation post cretaceous-paleogene extinction

Mammals had been small for 150 million years

radiated over the next 10 million years into similar diversity of animals we know today

Harmful environmental impact by bacteria?

Some bacteria release methane during cellular respiration. Large quantities of this methane is frozen under permafrost

permafrost is thawing due to climate change

release of this methane could exacerbate atmospheric green house gas levels

Order of major events? (oldest to most recent)

First evidence of life (3.4b)

Oxidative photosynthesis (3b)

Evidence of Oxygen in atmosphere (2.2b)

First eukaryotic organism (2 b)

Diversification of animals (540 mil)

First land plant (480 mil)

First bony fish / fish w jaws (440 mil ish)

First insects, vascular plants, trees, seed plants and tetrapods (400 mil ish)

End Permian extinction (250 mil)

First mammal (210)

First flowering plant (130)

Createous-Paleogene extinction (66 mill)

Adaptive radiation of mammals

First fully biped ape (5 mill)

Put these in order (oldest to most recent)

First flowering plant

First bony fish

end permian extinction

First bony fish

End Permian

First Flowering plant

What kind of elements do the oldest fossils contain?

Uranium-lead, Potassium-Argon

What kind of elements do newer fossils contain?

Radiocarbon

What area of the genome do we use when preforming Molecular Clock type questions, and why/

Introns because they are preseved throughout history

introns have no effect on phenotype so selection does not act on them thus preserving them

What is the formula for finding the amount of time that has passed since a lineage has split/ speciation has occured?

# of generations= (divergence ÷ mutation rate) x (0.5)

with divergence being the # of differences per site in the genome

and mutation rate being mutations per site, per generation

For Hardy Weinberg-- when do we use p + q = 1, and when do we use p² + 2pq + q² = 1

p + q = 1 is to determine the phenotypic frequency

p² + 2pq + q² = 1 is to determine genotype frequency

Which hardy weinberg equation can we use even if we do not know if we are working with a hardy weinberg equation

p + q = 1

When trying to determine the identity of an unknown organism given defining traits of it, why is it accurate to assume that even if it is not a bacteria, its genome most likely contains bacterial sequences of DNA?

Because of endosymbiosis-- majority of eukaryotes have ancient bacteria living within us (mitochondria)