3. notes and revision

Question 1

biodivesity

Answer 1

Biodiversity is the variety of all life on earth. It includes genetic diversity, species diversity and habitat diversity.

Question 2

Benefits of biodiversity

Answer 2

economic value
genetic divesity ie increaed survival rate

Humans benefit financially from biodiversity. Natural capital gives us goods that can be sold – such as timber, agricultural food crops, medicines and pharmaceutical drugs and the clothes we wear.

Biodiversity maintains genetic diversity and thus is important to the continuation of evolution increasing survival rate.

Question 2

Determinants of biodiversity

Answer 2

Climate
Age of the area
habitat range

Age of the area: Older areas tend to have higher biodiversity. This is due to the fact that a longer time-span allows organisms to diversify more and drive greater speciation.

Environmental stability: Some areas of the planet have experienced environmental disturbances (volcanic eruptions, earthquake or floods) and/or climatic disturbances (glaciations or drought) which may destroy large numbers of species. These areas have had less time for colonisation and species adaptation.

Range of habitats: A wide range of habitats will allow the organisms to move into new habitats and ecological niches, therefore evolving and driving speciation.

Question 3

Species diversity

Answer 3

Species diversity is the richness and evenness of the species.

Question 4

importance of genetic diversity

Answer 4

Increased survival rate
increased resiliance and adaptation
reduced extinction chances
prevention of inbreeding

There is a better chance that some members of the species will be resilient and survive environmental change caused by things such as disease, climate change and pollution.

Low genetic diversity (often caused by small populations) causes inbreeding which makes the genetic make-up of the population more uniform.

Extinction is frequently preceded by a drop in genetic diversity.

Question 4

how to measure species diversity

Answer 4

simpsons diversity index
N(N-1) / E n(n-1)

Question 5

Genetic diversity

Answer 5

Genetic diversity refers to the variation of genes within the genetic pool of a population of a species

Question 6

Advantages of habitat diversity

Answer 6

Promotes genetic diversity
increases adaptability
leads to speciation thus species diversity

Separation prompts greater variations in the gene pools.This results in higher genetic diversity.
High genetic diversity increases species adaptability and can lead to speciation and thus higher species diversity.

Question 6

Habitat diversity

Answer 6

Habitat diversity is the range of different habitats in an area.​

Question 7

Speciation

Answer 7

Speciation is the formation of a new species through biological processes.

Question 8

Factors affecting natural selection

Answer 8

VICS
1. variation -
This is the genetic diversity Within a population of one species
2. Inheritance
The offspring of fitter individuals may inherit the genes that give them that advantage.
3. Competitve advantage
Due to natural variation, some individuals will be fitter than others and therefore have a comparative advantage.
4. survival of the fittest
Fitter individuals are more likely to survive long enough to reproduce more successfully than individuals who are less fit.

Question 9

Natural selection

Answer 9

Natural selection is the gradual evolutionary change that results from genetic variation in each generation.

ggg

Question 10

Variation

Answer 10

This is the genetic diversity Within a population of one species

Question 11

Evolution

Answer 11

The gradual change in geentic chararcter of populations over many generations archived mostly through natural selection

ggg thru natural selection

Question 12

Steps to natural slection

Answer 12

1. Over population
2. variation
3. selection
4. adaptation

Question 13

Adaptation

Answer 13

this is an inheritred characterist that increases an organisms chance of survival

Question 14

plate tectonics

Answer 14

this is the continental drift theory that expalins the distribution of continents

Question 14

Isolation

Answer 14

This is when two populations get separated by environmental cahnges eg sea level change

Question 15

types of isolation

Answer 15

Geographic - physically separated
temporal - awake at different times of the day
behavioural - different mating rituals

Question 16

Endemic species

Answer 16

These are unique to a particular location and not found any where else eg lemurs of madagscar ie king julien

Question 17

*

divergent plate margins

Answer 17

divergent margins are where plates move apart and cause diversification

Question 18

convergent plate margins

Answer 18

where plates move together

Question 19

Mass extinction

Answer 19

Mass extinction is a sudden global decrease in the number of species over a relatively short period of time.

Question 20

Background or normal extinction

Answer 20

Background or normal extinction is the standard rate at which species go extinct.

Question 21

The BIG 5 extinctions

Answer 21

Ordovician-Silurian Extinction (around 445 million years ago):
Cause: Possibly glaciation, climate change, and/or volcanic activity leading to a drop in sea levels and global cooling.

Late Devonian Extinction (around 375-360 million years ago):
Cause: Likely a combination of climate change, oceanic anoxia (low oxygen levels), and habitat loss due to sea-level changes.

Permian-Triassic Extinction (around 252 million years ago):
Cause: Likely volcanic activity from the Siberian Traps, leading to massive global warming, ocean acidification, and habitat destruction.

Triassic-Jurassic Extinction (around 201 million years ago):
Cause: Possibly volcanic activity, asteroid impacts, or climate change, leading to habitat loss and widespread extinction of marine and terrestrial species.

Cretaceous-Paleogene Extinction (around 66 million years ago):
Cause: Most widely attributed to an asteroid impact at Chicxulub, Mexico, leading to massive environmental disturbances, including wildfires, tsunamis, and global cooling due to dust and debris in the atmosphere.

Question 21

causes of mass extinctions

Answer 21

1. Tectonic plate movements
2. super volcanic eruptions
3. climate change
4. meteorite impact

Question 22

Factors that help maintain biodiversity

AFFECTING MAINTANACE OF BIODIVERSITY

Answer 22

1. complexity of food webs
2. stages of succesion
3. limiting factors

Question 23

Factors leading to loss in biodiversity

Answer 23

1. Natural disaster
2. pollution
3. fragmentation - division of habitat into fragments

Question 23

Human activities causing extinction

Answer 23

1. over huntin
2. pollution
3. habitat destruction

Question 24

determinants of population sttatus or why on the IUCN Red List

Answer 24

1. population size
2. habitat destruction
3. habitat diversity ie if they found in one palce its bad
4. reproductivce potential ie r-strategists reproduce alot

Question 25

IUCN in full

Answer 25

International Union for Conservation of Nature (IUCN)

Question 25

Flagship species

Answer 25

These species often serve as symbols to raise awareness, garner public support, and mobilize action for broader conservation goals. Flagship species are typically chosen for their appeal to the public and their ability to capture attention, evoke emotional responses, and generate interest in conservation efforts.

Question 26

Reasons to conserve biodiversity

Answer 26

1. ecosytem services
2. food sources
3. medicines
4. ecotourism

Question 27

conservation vs preservation

Answer 27

Conservation aims to sustainably manage natural resources for human use, while preservation seeks to protect ecosystems and species in their natural state, often excluding human intervention.