unit 2.1 - Biodiversity

Question 1

What does the term phylogenic mean?

Answer 1

Evolutionary relatedness

Question 2

What are taxa?

Answer 2

Levels of classification

Question 3

What are the different taxa?

Answer 3

Domain - Did
Kingdom - King
Phylum - Phillip
Class - Come
Order - Over
Family - For
Genus - Good
Species - Soup?

Question 4

Why do we need phylogenetic classification?

Answer 4

• Allows us to infer evolutionary relationships.
• If a new animal is discovered with similar features to a taxa we can predict it’s characteristics using this method
• When describing the health of an ecosystem or the rate of extinction in the geological record, conservations often find it useful to count families than species

Question 5

What is a domain?

Answer 5

The largest taxon and all living things belong to one of the three domains

Question 6

What are the 3 domains and their features?

Answer 6

Eubacteria - familiar bacteria e.g E. coli and Salmonella. They are prokaryotes
Eukaryota - includes plantae, animalia, fungi and protoctista. They are all eukaryotic organisms.
Archaea - bacteria that have unusual metabolism e.g some produce methane. They live in marginal habitats and are also prokaryotes

Question 7

What do domains contain?

Answer 7

Kingdoms

Question 8

What are the 5 main kingdoms and their features?

Answer 8

1. Prokaryota - All bacteria, cyanobacteria, microscopic, single celled organisms with no membrane bound organelles. The cell wall is made out of peptidoglycan or murein
2. Protocista - Eukaryotic organisms, single celled, no tissue differentiation.
3. Fungi - Heterotrophic eukaryotes with cell wall made from chitin. They reproduce through spores
4. Planta - Multicellular eukaryotes, photosynthetic, cellulose cell walls.
5. Animalia - Multi cellular eukaryotes, heterotrophic, no cell wall, nervous coordination

Question 9

What are homologous structures?

Answer 9

• Have a similar arrangement of component parts and a similar developmental origin but different functions e.g the pentadactyl limb - flipper for swimming, wing for flying

Question 10

What are analogous structures?

Answer 10

• Have a corresponding function but different development origins e.g flipper on a whale or the fin on a shark

Question 11

What is sexual dimorphism?

Answer 11

Differences in size or appearance of sexes in an animal species e.g mane on a male lion but not on a lioness

Question 12

How can scientists define a species?

Answer 12

Morphologically - if two organisms look similar they are likely to be the same species
Reproductively - if two organisms can interbreed to produce fertile offspring

Question 13

What does the term biodiversity mean?

Answer 13

• Number of species or species richness
• Number of individual organisms within each species

Question 14

What can cause a decrease in biodiversity?

Answer 14

• Succession - organisms change their habitats to make it more suitable for other species
• Human impacts
• Weather
• Disease
• Competition
• Predation
• Availability
• Natural disasters

Question 15

What is causing the main decrease biodiversity?

Answer 15

Human destruction of habitat is the single greatest threat to biodiversity on the planet
Human activity has made the environments less hospitable to living organisms

Question 16

What does extinction mean?

Answer 16

Loss of species

Question 17

Why do we need to protect plants and animals? [4]

Answer 17

• Potential food sources
• Essential raw materials such as cotton, rubber and wood
• Useful chemicals and pharmaceuticals
• Disease resistant genes that can be GMed

Question 18

What is the calculation for the Simpsons index?

Answer 18

1 - number of each species <divide> total number of organisms
1 - n(n-1)/N(N-1)</divide>

Question 19

What is a SNP?

Answer 19

One base in the DNA differs
Single Nucleotide polymorphism

Question 20

What are HVRs and STRs?

Answer 20

Regions of DNA that vary in length, about 20-40 base sequences long often repeated
Hyper Variable Regions + Short Tandem Repeats

Question 21

What does it mean when a population has a lot of SNPs and HVRs?

Answer 21

More differences indicate a greater biodiversity

Question 22

What is genetic or DNA profile or fingerprints?

Answer 22

A pattern unique for each individual, related to the base sequence of their DNA

Question 23

What is adaptive radiation?

Answer 23

The formation of new species from a single common ancestor

Question 24

What is an anatomical trait?
Give an example in animals and plants

Answer 24

Adaption of a part of an organisms anatomy.
- Sharks and dolphins have streamlined bodies
- Plants have flowers with honey or nectar guides called beelines

Question 25

What is a physiological trait?
Give an example in plants and animals .

Answer 25

Traits that affect how am organism functions.
- In animals the production of anti freeze to withstand very cold conditions (polar bears and penguins)
- In plants the production of toxins to protect themselves

Question 26

What are behavioral traits?
Give an example in plants and animals .

Answer 26

When plants and animals behave in a certain way to give themselves a better chance at survival.
- In animals, mating rituals increase and animals chance of reproducing successfully
- In plants, growing towards the sun gives the plant a better chance at photosynthesis

Question 27

What is a species?

Answer 27

organisms that interbreed to produce fertile offspring