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Biodiversity & Natural Resources Flashcards

1
Q

BIODIVERSITY

Index of Biodiversity

Comparing Biodiversity of Different Habitats

A

Used to compare the Biodiversity of Different Habitats
Learn Index of Diversity Equation

Value of 1 means there is no diversity at al

N = total number of organisms of all species
n = total number of organsims of a particular species

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2
Q

BIODIVERSITY

Comparsion of 2 habitats

For Example: What needs to be measured in order to compare 2 rainforests

A

Measure Species Richness:
Count the number of different species
Determine Population Size:
Number of individuals per species

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3
Q

BIODIVERSITY

Definition of Biodiversity?

Measured by?

A

The variety of plant and animal life in a particular habitat.

Number of species within a habitat or Genetic Variation within a species.

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4
Q

BIODIVERSITY

Definition of Species?

A

A group of organisms that can interbreed to produce fertile offspring.

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5
Q

BIODIVERSITY

Definition of Species Richness?

A

Measures number of species in a habitat.

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6
Q

BIODIVERSITY

Measuring Genetic Diversity?

Equation

Definition of Heterzygote?

A

Calculate the heterozygosity index:
Number of heterozygotes/ number of individuals within a population

Heterozygote - an individual having two different alleles of a particular gene, giving rise to varying offspring.

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7
Q

BIODIVERSITY

Definition of Endemic?

A

A species that is found on only one geographical location.

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8
Q

BIODIVERSITY

Definition of Species Eveness?

A

How relatively abundant each of the species are

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9
Q

BIODIVERSITY

Definition of Niche?

Competition within an Niche?

A

A role that an organism plays in the ecosystem:
include biotic and abiotic interactions

Exploitation of a particular organsims environment

If 2 species attempt to occupy the same Niche, one will be out-competed untill only one species survives.

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10
Q

ADAPTATIONS

What are the 3 types of adaptations?

A
  1. Behavioual
  2. Physiological
  3. Anatomical
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11
Q

ADAPTATIONS

Behavioural Adaptation:

A

The way that an organism acts which increases it’s chance of survival.

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12
Q

ADAPTATIONS

Anatomical Adaptation

A

Strutural Features of an organism which increase its chance of survival.

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13
Q

ADAPTATIONS

Physiological Adaptation

Internal Features

A

Processes which occur within the body of an organism to increase chance of survival.

***Metabolic Reactions in response to a stimulus.

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14
Q

What is the effect of interbreeding on Genetic Diversity?

A
  • Increases the size of the gene pool

due to the introduction of new alleles into the population

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15
Q

NATURAL SELECTION

Definition of Natural Selection?

A

Process by which individuals with a favourable phenotype are more likely to survive and pass on alleles to offspring

Advantageous alleles increase in frequency over time

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16
Q

NATURAL SELECTION

Definition of Evolution?

A

Change in allele frequency within a population over time.

Allele = an alternative form of a gene

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17
Q

NATURAL SELECTION

How does natural selection lead to evolution?

A

Random Mutations = New Alleles
1. Advantageous allele frequency will increase overtime due to natural selection
2. Individuals without this will not survive long enough to reproduce
3. This means there is reduced competition for resources
4. Non advantageous allele frequency decreases
Changes to allele frequency leads to evolution within a population

Individuals with ADVANTAGEOUS ALLELE will pass on to their offspring - they are also more likey to survive.

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18
Q

NATURAL SELECTION

Why does Natural Selection Occur?

Types of Selection Pressures

A
  1. PREDATORS
  2. DISEASE
  3. COMPETITION

Results in differential survival and reproduction

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19
Q

NATURAL SELECTION

The Hardy- Weinburg Principle

A
  • Estimates the frequency of alleles in a population.
  • Estimates if allele frequency is changing over time.
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20
Q

NATURAL SELECTION

The Hardy- Weinburg Equation

Key:

A

P^squared + 2pq + q^squared = 1
p + q = 1

P = Homozygous Dominant Allele
pq = Heterozygous
q = Homozygous Recessive

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21
Q

NATURAL SELECTION

Definition of Speciation?

A

Development of a new species
- Population of a species become separated from eachother by geographical barriers

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22
Q

NATURAL SELECTION

Definition of Reproductive Isolation?

A

Occurs when changes in alleles and phenotypes of some individuals in a population:
* prevents them from successfully breeding with other individuals

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23
Q

NATURAL SELECTION

How does Speciation Occur?

A

SPLIT & ISOLATED POPULATION
different selection pressures acting on 2 groups
If genetic makeup changes so that groups can no longer interbreed
They become a new SEPERATE SPECIES

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24
Q

NATURAL SELECTION

How does reproduction and speciation cause the formation of a new species?

A

Random Mutation = change in allele frequencies
Population becomes split and isolated
If sufficient selection pressures change the gene pool of both populations that they can no longer interbreed…
POPULATIONS WILL DIVERGE AND FORM SEPARATE SPECIES

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25
# **NATURAL SELECTION** How do mutations lead to a population becoming a seperate species?
* Mutations results in prodution of new alleles * Selection pressure cause ADVATAGEOUS ALLELES * Frequency of advantageous alleles increases ( *more individuals survive and reproduce)* * After some time, population will not be able to reproduce with another species to produce fertile offspring
26
# **CLASSIFICATION** Definition of Classification
A means of sorting organisms into categories based on their relationships *using both genotypes and phenotypes.*
27
# **CLASSIFICATION** What are the 5 kingdoms in the model for Classification?
* Animalia * Plantae * Fungi * Protoctista * Prokaryote
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# **CLASSIFICATION** What is the Taxonomic Hierarchy of groups?
1. Kingdom 2. Phylum 3. Class 4. Order 5. Family 6. Genus 7. Species
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# **CLASSIFICATION** Name of the system in which each species is named? ## Footnote Meaning -
Bionomial System ## Footnote The first part of the name is the genus, the second part of the name is the species.
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# **CLASSIFICATION** Features of Kingdom Animalia
* Multicellular Eukaryotes * Heterotrophs **obtain energy by ingesting material from other organisms**
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# **CLASSIFICATION** Features of Kingdom Plantae
* Multicellular Eukaryotes * Autotrophs **make their own organic molecules by Photosynthesis**
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# **CLASSIFICATION** Features of Kingdom Fungi
* Multicellular Eukaryotes * Heterotrophs **absorb nutrients from decaying matter after external digestion**
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# **CLASSIFICATION** Features of Kingdom Protoctista
* Eukaryote * photosythesise/ feed on organic matter from other sources **For Example ; algae**
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# **CLASSIFICATION** Features of Kingdom Prokaryotae
* Prokaryotic Organisms **For Example; bacteria**
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# **CLASSIFICATION** Woese phylogenetic tree
**3 Domains:** * Archea * Bacteria * Eukaryota Contain RNA sequences that are unique to their domain.
36
# **CLASSIFICATION** Molecular Phylogeny?
The analysis of molecular differences in different organisms to determine the extent of their **evolutionary relationship.**
37
# **CLASSIFICATION** How can molecular phylogeny be used to show two populations are *reproductively isolated?*
1. Comparison of similarities and differences in DNA 2. Comparison of Nucleotide Sequences 3. Greater number of differences , more likely to be reproductively isolated.
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# **CLASSIFICATION** How does the scientific community evaluate the data?
* Findings published in *scientific journals* * Presented at *scientific conferennces* * **PEER REVIEW**
39
# **PROPERTIES OF PLANTS** STRUCTURE AND FUNCTION | Plant Cell Wall
* Made of Cellulose Outer Layer = **Middle Lamella** Holds adjacent cells together Provides support and protection
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# **PROPERTIES OF PLANTS** STRUCTURE AND FUNCTION | Chloroplast
Contained thylakoid membranes which are stacked into grana. * Contain chlorophyll Surrounded by the **stroma** = liquid containing photosynthetic enzymes
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# **PROPERTIES OF PLANTS** STRUCTURE AND FUNCTION | Amyloplasts
Produces and stores starch * Composed of amylose & amylopectin | - Surrounded by a double membrane
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# **PROPERTIES OF PLANTS** STRUCTURE & FUNCTION | Vacuole
* provides cell support * Storage for nutrients needed as well as waste materials before removal Sac filled with cell sap | Vacuole is surrounded by a single membrane, tonoplast
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# **PROPERTIES OF PLANTS** STRUCTURE & FUNCTION | Plasmodesmata
Connect neighbouring cells together - allows transport of substances between them
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# **PROPERTIES OF PLANTS** STRUCTURE & FUNCTION | Pits
Thin sections of cell wall which allows: * Easy diffusion * Enables substances to be transferred between them
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# **PROPERTIES OF PLANTS** Structure of Cellulose
* Polymer of Beta Glucose * Contains 1,4 glycosidic bonds * Every other glucose molecule = inverted * In an *unbranched straight chain* ## Footnote Hydrogen bonds join adjacent cellulose molecules together in a cellulose microfibril
47
# **PROPERTIES OF PLANTS** Structure of Starch
* Polysaccharide made from alpha glucose Monomers = chains joined by **1,4 glycosidic bonds** Branches = joined to chains by **1,6 glycosidic bonds** *Contains amylose & amylopectin*
48
# **PROPERTIES OF PLANTS** How does starch relate to its function as a storage molecule?
* Contains glucose needed for respiration * Insoluble so has no osmotic effect Contains amylose & amylopectin: **Amylose =** coiled making starch compact , more energy can be stored **Amylopectin=** branched so can be rapidly hydrolysed
49
# **PROPERTIES OF PLANTS** STRUCTURE | Comparison between Cellulose & Amylopectin
* Both polymers of glucose * Both contain 1,4 glycosidic bonds Cellulose contains **beta glucose** whereas amylopectin contains **alpha glucose** Amylopectin contains **1,6 glycosidic bonds** whereas cellulose does not
50
# **PROPERTIES OF PLANTS** Suitable for energy storage? | Amylopectin and Glycogen
* Branched so can be rapidly hydrolysed to release glucose * Compact so more energy can be stored * Insoluable so does not have an effect on osmosis * *Energy molcules are too large to diffuse across cell membrane so they can be stored well*
51
# **PROPERTIES OF PLANTS** How does the structure of Cellulose relate to its function?
Long beta glucose chains are held together by *hydrogen bonds* to form **microfibrils** Hydrogen bonds = strong So, cellulose is well suited to providing structural support.
52
# **PROPERTIES OF PLANTS** Xylem Vessels
Long cylinders of dead tissue with open ends * Transport Water & Minerals as well as providing *structural support* | Thickened with a tough substance called lignin ## Footnote - Inside of Vascular Bundles
53
# **PROPERTIES OF PLANTS** What is the purpose of Lignin in the cell walls?
Strength & WaterProofing ## Footnote Example - In Xylem & Sclerenchyma
54
# **PROPERTIES OF PLANTS** Sclerenchyma Fibres
* Dead cells with a *hollow lumen* and *end walls* Provide structural support | Also thickened with a tough substance called lignin
55
# **PROPERTIES OF PLANTS** How do cells become lignified? | Example - Xylem & Sclerenchyma
Polymer lignin impregnates the the cellulose wall
56
# **PROPERTIES OF PLANTS** How are Xylem Vessels formed?
* After lignification entry of water and solutes into cells are restricted * Tonoplast Breaks down - Autolysis occurs **Leaves dead empty cells that form a tube** ## Footnote Autolysis = Cell starts to breakdown, cell membrane dissolves and enzymes & other cell contents spill out and digest surrounding tissues.
57
# **PROPERTIES OF PLANTS** Phloem Vessels
* Tubes made of living cells Involved in **translocation** ## Footnote Translocation - Movement of food substances and nutrients from leaves to storage organs.
58
# **PROPERTIES OF PLANTS** How does the structure of Xylem & Sclerenchyma relate to its function?
**cellulose microfibrils** form a net like arrangement in the cell walls of the fibres. Secondary thickening (lignin) strengthens fibre further | Fibre = structually supports the plant
59
# **PROPERTIES OF PLANTS** Vascular Bundles | Components for Transport and Support
* Xylem Vessels * Phloem Vessels * Cambium Cells * Sclerenchyma Fibres * Parenchyma Cells | Cabium Cells - undifferentiated cell, can specialise as plant grows ## Footnote Parenchyma cells - acts as packing cells between other cells and vessels
60
# **PROPERTIES OF PLANTS** Importance of Water in Plants
* Required for photosynthesis * Maintain rigidity of cells * Transport of substances * Thermoregulation
61
# **PROPERTIES OF PLANTS** Why are plant fibres useful for humans?
1. Sustainable & Renewable Resource 2. Products are Biodegradable 3. Strong and Cheap 4. Can be used to make *bioplastics and bioethanol*
62
# **PROPERTIES OF PLANTS** What are the 3 organic ions important to plants?
- Nitrate Ions - Magnesium Ions - Calcium Ions
63
# **PROPERTIES OF PLANTS** Function of Nitrate Ions? | How are they transported from root to the leaves.
Supply Nitrogen for production of DNA, proteins and chlorophyll. | Through Xylem vessels in water - Transpiration Stream
64
# **PROPERTIES OF PLANTS** Importance of calcium and magnesium in plants?
* Calcium = Form *calcium pectate* for cell walls growth. * Magnesium = Chlorophyll production and Enzyme activation.
65
# **PROPERTIES OF PLANTS** What are the effects of a shortage of **magnesium ions**?
* Shortage = limits chlorophyll production * Lack of glucose due to less photosynthesis * Cause stinted growth/ discolouration of leaves.
66
# **PROPERTIES OF PLANTS** Sustainability | Definition ## Footnote How can using plant products improve this?
Using resources in a way that also maintains them for future generations. ## Footnote Plants Fibres = biodegradable & cheap Starch = extracted from crops and can be regrown
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# **DRUG TESTING & DEVELOPMENT** Drug Testing | William Withering
* Potential useful substance identified * Trial on small group of paitents with disease * Large group of paitents used * General Use
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# **DRUG TESTING & DEVELOPMENT** Drug Testing | Modern Day
1. Potential useful substances found 2. Active ingredient identified 3. Pre Clinical Trial on Animals - Safety/ Toxicity/ Efficacy 4. Stage 1 **Review of Data** 5. Stage 2 6. Stage 3 **Approval for Use**
69
# **DRUG TESTING & DEVELOPMENT** Drug Testing - Stages of Testing | Stage 1
Drug Tested on HEALTHY individuals to test for side affects
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# **DRUG TESTING & DEVELOPMENT** Drug Testing - Stages of Testing | Stage 2
Drug is tested on a group of paitents
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# **DRUG TESTING & DEVELOPMENT** Drug Testing - Stages of Testing | Stage 3
Drug Tested on a LARGE GROUP of paitents 1 group recieves *existing treatment* others recieve *new treatments*
72
# **DRUG TESTING & DEVELOPMENT** Describe how clinical trials of a vaccine would be conducted?
1. Small group of healthly volunteers are given volume to test for side affects. 2. A group of people at risk of contracting disease is given the vaccine. 3. People who develop disease are monitored.
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# **DRUG TESTING & DEVELOPMENT** The role of a *placebo* in producing valid conclsions. | Stage 3
**Placebo** provides control group for comparison This ensures active ingredient is causing the effect.
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# **DRUG TESTING & DEVELOPMENT** The role of a *double blind trial* in producing valid conclusions. | Stage 3
**Double blind trial,** neither doctors or paitents know who has been given the drug. *Ensures bias is removed from the trial*
75
# **DRUG TESTING & DEVELOPMENT** How can a safe dose of serious illness drug be determined?
* Test the drug on HEALTHY individuals * Test drug on a group of individuals WITH ILLNESS * Gradually INCREASE dosage to determine its effects
76
# **DRUG TESTING & DEVELOPMENT** Conditions required for bacterial growth.
- Correct Temperature & PH for metabolic enzymes - Source of nutrients required for respiration - Suppy of Oxygen (for aerobic bacteria)
77
# **CONSERVATION** Definition of Conservation
The protection & management of species & habitat In order to maintain biodiversity
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# **CONSERVATION** What are Captive Breeding Programmes?
Endangered species are carefully bred to increase genetic diversity and population size.
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# **CONSERVATION** How would captive breeding programmes prevent a species becoming endangered?
* Relocation causes reproductive isolation * Use of studbook * Increase in number of another species * Reintroduction to naitive habitat
80
# **CONSERVATION** Role of Zoos in animal conservation?
* **Protection** from poachers * **Repopulation** - species can increase in numbers * **Education about conservation** - importance of breeding programmes * **Research** - discovering better nutrition to improve animal health
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# **CONSERVATION** Explain how breeding programmes in zoos maintain genetic diversity of *captive populations.*
* Animals are selected to prevent an interbreeding depression * A stud book is used to select individuals for mating * There is an **exchange of animals** between zoos.
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# **CONSERVATION** EX-SITU CONSERVATION | Advantages & Disadvantages ## Footnote Examples - Captive Breeding Programmes & Seed Banks
ADVANTAGES - Requires little space, predators & poachers DISADVANTAGES - Expensive , disease spreads quickly & can't fully recreate natural habitat.
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# **CONSERVATION** Purpose of Seed Banks?
Store a large number of seeds to conserve genetic diversity and prevent plant species from going extinct.
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# **CONSERVATION** Suitable Conditions for keeping seeds in a bank.
Cold & Dry Conditions
86
# **CONSERVATION** Benefit of drying seeds before storage?
Extends storage time of seeds - *As drying prevents germination of seeds*

A Level Biology Flashcards (8 decks)

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