BIOL 300: Exam 4, Module 15: Biodiversity

What is biology?

The study of life

How many species have been estimated to exist on Earth? How many species do we have actual documentation to exist?

Estimate: 2 - 11 million

Confirmed: 1.5 million

What are some examples of the most well-studied groups of organisms?

Charismatic megafauna, mammals, birds

What are some examples of the most least-studied groups of organisms?

Fungi, spiders, bacteria, fish, worms, deep sea species

What is an okapi?

An okapi is a forest giraffe

Define biodiversity

Biodiversity is all of the variety of Species on a planet

What specific components are included in the definition of Biodiversity?

genetic diversity, various ecosystems, and natural processes

Name the five mass extinction events described in the source, along with their approximate time ago and the life forms most affected.

1. end-ordividian / 440 mil yrs ago / marine life

2. end-devonian / 360 mil yrs ago / marine life

3. end-permian / 250 mil yrs ago / marine life

4. end-triassic / 200 mil yrs ago / marine life & terrestrial reptile

5. end-cretaceous / 65 mil yrs ago / dinosaurs

Are scientists currently saying we are experiencing a 6th mass extinction? What is their perspective?

We are currently experiencing the rate of a mass extinction, but we have not yet hit the threshold to be considered a mass extinction; however, if we keep up at the current rate we’re going, we will have one

What are the different ways we can classify different living things?

• Size, color, shape

• DNA

• Habitat and behavior

Define taxonomy

Classification of living things based on evolutionary history

All of life fits into one of three domains:

1. bacteria

2. archae

3. eukaryota

Name the four Kingdoms within the Domain Eukarya

1. protista

2. animalia

3. plantae

4. fungi

Name some of the characteristics of kingdom protista

• mostly single-celled (except Kelp!)

• no real unifying characteristics

• some have cell walls

• some are motile

• some are heterotrophic

Name some of the characteristics of kingdom animalia

• multicellular

• motile

• heterotrophic

• no cell wall

Name some of the characteristics of kingdom plantae

• multicellular

• not motile

• autotrophic

• cellulose-based cell wall

Name some of the characteristics of kingdom fungi

• multicellular (except Yeast!)

• chitin-based cell walls

• heterotrophic

List the characteristics used to define life

1. reproduce

2. reacts to stimuli

3. evolves

4. uses and assimilates energy

5. cellular

6. homeostasis

7. DNA

What are some specific examples of human homeostasis?

• 37 degrees Celsius (Body Temperature),

• Blood pH of 7.4,

• Blood sugar (glucose) 0.1%

Is organism-level homeostasis the same thing as chemical equilibrium?

No

What is the definition of chemical equilibrium?

Chemical equilibrium is a balance between different chemicals