U3 T1 - Describing Biodiversity

Question 1

Classification of an organism can be based on?

Answer 1

Similarity of physical features
Methods of reproduction
Molecular sequences

Question 2

Species definition

Answer 2

group of organisms that can potentially interbreed, or mate, with one another to produce viable, fertile offspring.

Question 3

example of an interspecfic Hybrid

Answer 3

Mule made from a donkey and a horse

Question 4

Describe the Linnean classification system

Answer 4

Kingdom,Phylum,Class, Order, Family, Genus, Species

Question 5

Describe the methods of reproduction classification system

Answer 5

reproduce either Asexually (1 parent with no variation) or sexually (2 parents with variation)
r- Strategiests- short life span- high rate of reproduction, quick to mature
K- strategists- low offspring, higher gestation period, higher survival rate

Question 6

describe the molecular sequences classification system

Answer 6

Phylogeny- evolutionary relationships between organisms
cladistics- when similarity in molecular sequences is used to define a group of organisms

Question 7

predation

Answer 7

prey numbers regulate predator numbers
presance of predators impacts ecosystem dynamics

Question 8

competition

Answer 8

organisms within an ecosystem use the same resources
both species are negatively affected

Question 9

symbiosis

Answer 9

symbiotic relationships exist between species and have at least 1 member benefiting
mutualism- both benefit
commensalism- one benefits, other unaffected
paratism- one benefits, other is harmed

Question 10

Disease

Answer 10

the harm to a living thing and can involve the interatction between a pathogen and a host

Question 11

Clade definition

Answer 11

group of organisms that includes an ancestor and all the proposed decsendants of that ancestor, also known as a monophyletic group

Question 12

what are the common assumptions of cladistics

Answer 12

common ancestry-organisms within a group are decended from a common ancestor
Bifurcation- there is a bifucating pattern (dividing a branch into 2)
Physical change- physical change occurs over time

Question 12

describe a cladogram

Answer 12

More Simplistic then Phylogram
No time scale

Question 13

Molecular evidence

Answer 13

if two species have similar proteins or DNA sequences it is used as molecular evidence that they shared a recent common ancestor.

Question 14

What are ecyosystems composed of?

Answer 14

Habitats:
Microhabitats- very small habitats
Ecoregions- ecosystems covering large biogeographical areas

Question 15

How are ecosystems classified

Answer 15

The interaction of organisms and the abiotic factors

Question 16

how is the process of classifying ecosystems an important step towards effective ecosystem management

Answer 16

It helps to understand the importance of an ecosystem and understanding the unique interactions and the steps requried to preserve them.
Example: Old growth forests protect many endagered species and logging is not permitted to prevent habitat destruction and the relase of large amounts of carbon dioxide.

Question 17

how can ecosystems be compared

Answer 17

spatial scale- comparing across areas
temporal scale- comparing across time
species interaction- predation, symbiosis, compettition, disease
Abiotic factors- climate, soil type, precipitation, light levels

Question 18

what is the purpose of stratified sampling

Answer 18

estimate:
population
distribution
enviromental gradients/profiles
zonation
stratification

Question 19

Site selection in stratified sampling

Answer 19

sites must be selected from each strata that are fairly homogenous and representative of the larger population
randomisation is used to minimise bias

Question 20

minimising bias when stratified sampling

Answer 20

Law of large numbers- greater number of samples = greater chance the samples represent the community
random number generators- used to pick grid coordinates for transects or quadrats
Counting Criteria- Establishing clear parameters for counting organisms
Calibration of Equipment- Regular servicing and calibration of equipment and acknowledgment of precision

Question 20

choise of ecological surveying technique when stratifed sampling

Answer 20

Transects- measure change in distribution and abiotic factors
Quadrats- Measure density

Question 21

Biodiversity

Answer 21

Biodiversity is the variety of organimsms living within an ecoystem, including the diversity of species and ecosystems

Question 22

Determining diversity using percentage cover

Answer 22

measures the proportion of an area covered by an organism to measure abundance

Question 22

Explain how environmental factors limit the distribution and abundance of species in an ecosystem

Answer 22

Each species has a set of enviromental conditions required for their survival known as a tolerance range.
Example- in a cold climate metabolism can be slowed and also slow growth of plants resulting in limited species being able to survive from limited food supplies

Question 23

Determining diversity using percentage frequency

Answer 23

Measures the apperance of of plant species in quadrats.

Question 24

Determining diversity using species richness

Answer 24

measures the number of species within an area`

Question 25

Determining diversity using species abundance and evenness

Answer 25

-species abundance is the number of individuals of a species in the ecosystem

-Species evenness is a measure of individuals of a species in relation to the total number of all species in the area

Question 26

Determining diversity using simpsons diversity index

Answer 26

SDI takes into account both species evenness and richness
A value of 0 means a monoculture of 1 species
a value of 1 indicates infinite diversity