Topic 4 Biodiversity Flashcards
1
Q
What is biodiversity?
A
Biodiversity is the variety of living organisms in an area
It includes genetic diversity, species diversity, and ecosystem diversity.
2
Q
What are the components of biodiversity?
A
- Genetic diversity
- Species diversity
- Ecosystem diversity
These components contribute to the overall health of ecosystems.
3
Q
Define genetic diversity.
A
Genetic diversity is the variation of alleles within a species or a population of a species
Example: Human blood type is determined by a gene with three different alleles.
4
Q
What is endemism?
A
Endemism is when a species is found only in one specific location and nowhere else
Endemic species are particularly vulnerable to extinction.
5
Q
How has natural selection affected biodiversity?
A
Natural selection has increased biodiversity on Earth over time
However, human activities are reducing species diversity.
6
Q
What human activities are reducing biodiversity?
A
- Farming
- Deforestation
These activities lead to habitat loss and decreased species diversity.
7
Q
Why is conservation important?
A
Conservation is needed to help maintain biodiversity and protect endemic species
Endemic species are particularly vulnerable as they cannot migrate if their habitat is threatened.
8
Q
What is a habitat?
A
A habitat is the place where an organism lives, such as a rocky shore or a field
Measuring species diversity helps compare different habitats.
9
Q
How can species diversity in a habitat be measured?
A
- Count the number of different species (species richness)
- Count the number of individuals in each species and use an index of diversity
Species richness does not indicate the abundance of each species.
10
Q
What is species richness?
A
Species richness is the number of different species in an area
A higher number of species indicates greater species richness.
11
Q
What is sampling in the context of measuring biodiversity?
A
Sampling involves selecting a small area within a habitat to estimate species diversity
This helps avoid bias and provides a better indication of the whole habitat.
12
Q
What sampling methods can be used for different organisms?
A
- Quadrat for plants
- Sweepnet for flying insects
- Pitfall trap for ground insects
- Net for aquatic animals
Different methods are tailored to the type of organism being studied.
13
Q
What is genetic diversity within a species?
A
Genetic diversity within a species refers to the variety shown by individuals of that species
Individuals vary because they have different alleles.
14
Q
What is the gene pool?
A
The gene pool is the complete set of alleles in a species or population
Greater variety of alleles indicates greater genetic diversity.
15
Q
What does phenotype describe?
A
Phenotype describes the observable characteristics of an organism
Different alleles can code for slightly different phenotypes.
16
Q
How can genetic diversity be measured?
A
- Analyzing DNA sequences
- Observing different phenotypes in a population
The larger the number of different phenotypes, the greater the genetic diversity.
17
Q
What is the heterozygosity index?
A
The heterozygosity index measures genetic diversity within a species based on the proportion of heterozygotes
A higher proportion of heterozygotes indicates greater genetic diversity.
18
Q
How is the heterozygosity index calculated?
A
H = number of heterozygotes / number of individuals in the population
This index can estimate genetic diversity in the whole genome of the population.
19
Q
Calculate the heterozygosity index for a population of 456 fruit flies with 276 heterozygous individuals.
A
H = 276 / 456 = 0.61
This value indicates the genetic diversity at the locus for eye color.
20
Q
What is biodiversity?
A
The variety of life in a particular habitat or ecosystem.
21
Q
What does endemism refer to?
A
A species that is native to and restricted to a specific geographical area.
22
Q
What is the formula for calculating the index of diversity (D)?
A
D = N(N - 1) / Σn(n - 1)
23
Q
In the context of biodiversity, what do N and n represent?
A
- N = Total number of organisms of all species
- n = Total number of organisms of one species
24
Q
What does a higher index of diversity indicate?
A
A more diverse area.
25
What is species richness?
The number of different species represented in a given area.
26
What does the heterozygosity index (H) measure?
The genetic variation within a population.
27
What is a niche?
The role of a species within its habitat.
28
What are the three ways organisms can be adapted to their niche?
* Behavioral adaptations
* Physiological adaptations
* Anatomical (structural) adaptations
29
Give an example of a behavioral adaptation.
Possums sometimes 'play dead' when threatened.
30
Give an example of a physiological adaptation.
Brown bears hibernate to conserve energy.
31
Give an example of an anatomical adaptation.
Otters have a streamlined shape for gliding through water.
32
What happens when two species try to occupy the same niche?
They will compete, and one species will be more successful than the other.
33
True or False: An index of diversity only considers species richness.
False.
34
What is the importance of calculating an index of diversity?
It allows for comparison of species diversity in different habitats.
35
What is an example of a structural adaptation in whales?
A thick layer of blubber to keep warm.
36
What is the role of enhanced field margins in biodiversity?
They provide habitat for wildlife and increase species diversity.
37
What is the significance of echolocation in bats?
It helps them locate and catch insects.
38
What is a mutation?
A change in the DNA sequence that can lead to variation in phenotypic characteristics.
39
What are selection pressures?
Factors such as predation, disease, and competition that create a struggle for survival.
40
What is natural selection?
A process by which individuals with advantageous adaptations are more likely to survive and reproduce.
41
What is an advantageous allele?
An allele that increases an individual's likelihood of survival and reproduction.
42
How does natural selection lead to evolution?
Over generations, the frequency of advantageous alleles increases, leading to changes in the population.
43
Who proposed the theory of evolution by natural selection?
Charles Darwin.
44
What is speciation?
The development of a new species from a population.
45
Define reproductive isolation.
When populations of the same species cannot successfully breed due to changes in alleles and phenotypes.
46
What are the types of changes that can lead to reproductive isolation?
* Seasonal changes
* Mechanical changes
* Behavioral changes
47
What is geographical isolation?
A physical barrier that divides a population, leading to different selection pressures.
48
What can cause geographical isolation?
* Floods
* Volcanic eruptions
* Earthquakes
49
How do allele frequencies change due to natural selection?
Different characteristics become more common based on their advantage in specific environments.
50
What is phenotypic variation?
The differences in observable traits among individuals in a population.
51
Fill in the blank: A species is defined as a group of similar organisms that can reproduce to give _______.
[fertile offspring]
52
True or False: Dark-colored peppered moths became more common due to better camouflage against blackened trees.
True
53
What happens to populations separated by a barrier over time?
They may evolve into separate species due to changes in allele and phenotype frequencies.
54
What is the effect of climate change on tawny owls in Finland?
Darker brown owls have become more common due to decreased snowfall affecting survival.
55
Explain the role of mutations in evolution.
Mutations introduce new alleles, contributing to variation and the potential for adaptation.
56
What is the significance of evidence in scientific theories?
The more evidence there is, the more confidence scientists have in a theory.
57
Fill in the blank: The process by which individuals with better adaptations survive and reproduce is called _______.
[natural selection]
58
What can lead to changes in phenotype frequencies?
Changes in allele frequencies due to natural selection and mutations.
59
What is allele frequency?
How often an allele occurs in a population, expressed as a percentage or a decimal.
60
What does the Hardy-Weinberg Principle predict about allele frequencies?
The frequencies of alleles in a population will not change from one generation to the next under certain conditions.
61
What conditions must be met for the Hardy-Weinberg Principle to apply?
* Large population
* No migration
* No emigration
* No mutations
* No natural selection
* Random mating
62
What is the equation for allele frequencies in a population with two alleles?
p + q = 1
63
What do the variables p and q represent in the Hardy-Weinberg equation?
* p = frequency of the dominant allele
* q = frequency of the recessive allele
64
How do you calculate the frequency of the recessive allele given the frequency of the dominant allele?
q = 1 - p
65
What is the Hardy-Weinberg equation for genotype frequencies?
p² + 2pq + q² = 1
66
What do the terms in the Hardy-Weinberg equation for genotype frequencies represent?
* p² = frequency of homozygous dominant genotype
* 2pq = frequency of heterozygous genotype
* q² = frequency of homozygous recessive genotype
67
If the frequency of allele R (red) is 0.4, what is the frequency of allele r (white)?
0.6
68
How can genotype frequencies be used to calculate phenotype frequencies?
Add the genotype frequencies of all genotypes that produce the same phenotype.
69
True or False: The Hardy-Weinberg Principle applies if allele frequencies change over generations.
False
70
What does a change in allele frequency over generations indicate?
Factors like immigration, emigration, mutations, or natural selection have affected the population.
71
What is classification in biology?
Grouping together similar organisms
72
How many levels of taxonomic groups are used in classification?
Eight levels
73
What is the hierarchy of biological classification from broadest to most specific?
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
74
What happens to the number of groups and organisms as you move down the hierarchy?
More groups at each level but fewer organisms in each group
75
What is the species concept?
Species are groups that contain only one type of organism that cannot breed together to produce fertile offspring
76
What is the binomial naming system?
A system where all species are given a unique scientific name in Latin consisting of two words: genus name and species name
77
What is an example of a binomial name for humans?
Homo sapiens
78
What are the three main criteria for classifying organisms?
Phenotypes, genotypes, and relatedness
79
True or False: Early classification systems only used observable phenotypes.
True
80
What are the five kingdoms of life?
* Prokaryotae (Monera)
* Protoctista
* Fungi
* Plantae
* Animalia
81
What is the primary feature of organisms in the Prokaryotae kingdom?
Unicellular, no nucleus, less than 5 um
82
What distinguishes organisms in the Plantae kingdom?
Eukaryotic, multicellular, cell walls made of cellulose, autotrophic
83
What is molecular phylogeny?
The study of evolutionary history based on DNA and protein similarities
84
What are the three domains in the three domain classification system?
* Archaea
* Bacteria
* Eukaryota
85
How are organisms from the Prokaryotae kingdom classified in the three domain system?
Separated into two domains: Archaea and Bacteria
86
What is the significance of new data in classification systems?
It can lead to reclassification and changes in the classification system structure
87
Fill in the blank: The classification of the brown trout includes Domain: ______, Phylum: Animalia, Class: ______.
Eukaryota, Actinopterygii
88
Explain how you know that a brook trout and a brown trout are different species.
They cannot produce fertile offspring (tiger trout are not fertile)
89
What causes a reduction in global biodiversity?
The extinction of a species or the loss of genetic diversity within a species
## Footnote
This includes species that are at risk of extinction due to low population or threatened habitat.
90
What is the role of zoos and seedbanks in conservation?
They help conserve endangered species and genetic diversity.
91
What is a seedbank?
A store of seeds from different species of plants, especially endangered ones.
92
How do seedbanks help conserve biodiversity?
By storing seeds of endangered plants that can be used to grow new plants if they become extinct in the wild.
93
What is an advantage of using seedbanks over growing plants?
It's cheaper to store seeds than to store fully grown plants.
94
List three advantages of seedbanks.
* Cheaper to store seeds than plants
* Larger numbers of seeds can be stored
* Less labor is required to look after seeds
95
What are two disadvantages of using seedbanks?
* Testing seeds for viability can be expensive and time-consuming
* Difficult to collect seeds from remote locations
96
What are captive breeding programmes?
Breeding animals in controlled environments to increase their numbers.
97
Why are pandas bred in captivity?
Because their numbers are critically low in the wild.
98
True or False: Captive breeding programmes are universally accepted as ethical.
False
99
What is a potential benefit of reintroducing organisms from zoos and seedbanks to the wild?
It can increase their numbers in the wild and help restore lost habitats.
100
What is one problem that can arise from reintroducing organisms to the wild?
Reintroduced organisms could bring new diseases to habitats.
101
What research can be conducted using seedbanks?
Studying how plant species can be successfully grown from seeds.
102
What is a disadvantage of studying plants from seeds in a seedbank?
It limits the data to small, interbred populations, which may not be representative of wild plants.
103
How do zoos contribute to scientific research?
They increase knowledge about the behavior, physiology, and nutritional needs of animals.
104
List two ways zoos educate people about conserving biodiversity.
* Allowing close encounters with organisms
* Providing training and setting up local seedbanks
105
What is the Millennium Seed Bank Project?
A project aiming to conserve seeds in their original country.
106
Fill in the blank: Conservation involves the protection and management of _______.
[endangered species]
107
What does conservation involve?
The protection and management of endangered species
## Footnote
Conservation aims to prevent extinction and maintain biodiversity.
108
What is a seedbank?
A store of lots of seeds from lots of different species of plant
## Footnote
Seedbanks help conserve biodiversity by preserving seeds of endangered plants.
109
How do seedbanks contribute to genetic diversity?
They store a range of seeds from plants with different characteristics
## Footnote
This includes seeds from plants with different alleles.
110
What are the work processes involved in seedbanks?
Creating cool, dry conditions for storage, testing seeds for viability
## Footnote
Viability testing involves planting seeds, growing plants, and harvesting new seeds.
111
List some advantages of using seedbanks.
* Cheaper to store seeds than fully grown plants
* Larger numbers of seeds can be stored
* Less labor is required
* Seeds can be stored in various locations
* Less likely to be damaged than plants
112
List some disadvantages of using seedbanks.
* Testing seeds for viability can be expensive and time-consuming
* Difficult to store all types of seeds
* Challenges in collecting seeds from remote locations
113
What are captive breeding programmes?
Breeding animals in controlled environments to increase their numbers
## Footnote
These programmes are typically for endangered or extinct-in-the-wild species.
114
Give an example of an animal involved in captive breeding.
Pandas
## Footnote
Pandas are bred in captivity because their numbers are critically low in the wild.
115
True or False: Reintroduction of organisms can help restore lost habitats.
True
## Footnote
Reintroduction can aid in habitat restoration, such as rainforests.
116
What are some potential problems with reintroducing organisms to the wild?
* New diseases could be introduced
* Animals may struggle to adapt to the wild
* Difficulties in finding food or communicating
117
How do seedbanks and zoos contribute to scientific research?
They allow for the study of plant species and animal behavior
## Footnote
This research aids conservation efforts and helps develop new crops or materials.
118
What is one disadvantage of studying plants from seeds in a seedbank?
The data may be limited to small, interbred populations
## Footnote
This limits the representativeness of the findings for wild plants.
119
How do zoos help educate the public about biodiversity?
They allow close encounters with organisms and raise awareness about conservation
## Footnote
Zoos also contribute to training and establishing local seedbanks.
120
Fill in the blank: The _______ Seed Bank Project aims to conserve seeds in their original country.
Millennium
## Footnote
This project focuses on global seed conservation efforts.
121
What is the function of xylem vessels?
To transport water and mineral ions up the plant and provide support.
## Footnote
Xylem vessels are long, tube-like structures formed from dead cells, allowing for efficient water transport.
122
Describe the structure of xylem vessels.
Long, tube-like structures formed from dead cells, with a hollow lumen and thickened walls made of lignin.
## Footnote
Xylem vessels have no end walls, creating an uninterrupted tube.
123
What is the role of sclerenchyma fibres?
To provide support; they are not involved in transport.
## Footnote
Sclerenchyma fibres are made of bundles of dead cells running vertically up the stem.
124
How do sclerenchyma fibres differ from xylem vessels?
Sclerenchyma fibres have end walls and contain more cellulose than xylem vessels.
## Footnote
Unlike xylem, sclerenchyma fibres do not have pits in their walls.
125
What is the primary function of phloem tissue?
To transport organic solutes, mainly sugars like sucrose, from where they're made to where they're needed (translocation).
## Footnote
Phloem is purely a transport tissue and does not provide support.
126
What are sieve tube elements?
Living cells joined end to end to form sieve tubes, allowing solutes to pass through the end walls with holes.
## Footnote
Sieve tube elements have no nucleus and a very thin layer of cytoplasm.
127
What is the function of companion cells?
To carry out living functions for themselves and sieve tube elements, including active transport of solutes.
## Footnote
Companion cells provide the energy needed for the transport process.
128
Fill in the blank: Xylem and phloem are found in _______.
vascular bundles
129
True or False: Sclerenchyma fibres are involved in the transport of water.
False
## Footnote
Sclerenchyma fibres provide structural support but do not participate in transport.
130
What substance thickens the walls of xylem vessels?
lignin
131
What is translocation in the context of phloem tissue?
The process of transporting organic solutes from their production site to where they are needed.
132
How can you identify xylem vessels and phloem tissue under a microscope?
By preparing thin cross-sections of plant stems and staining them, typically with toluidine blue O (TBO).
## Footnote
TBO stains lignin blue-green, allowing identification of xylem vessels and sclerenchyma fibres.
133
What is the difference between transverse and longitudinal cross-sections?
Transverse sections cut at a right angle to the length, while longitudinal sections are taken along the length of a structure.
134
List the components typically found in vascular bundles.
* Xylem vessels
* Phloem tissue
* Sclerenchyma fibres
135
What should be done to prevent cut sections of plant stems from drying out?
Place them in water until ready to use.
136
Describe the arrangement of xylem and phloem in the stem.
Xylem vessels are usually situated towards the interior, while phloem tissue is located towards the exterior in vascular bundles.
137
What is the main energy storage material in plants?
Starch
## Footnote
Starch is stored in plants as excess glucose and can be broken down to release glucose when needed for energy.
138
What two polysaccharides make up starch?
* Amylose
* Amylopectin
## Footnote
Amylose is a long, unbranched chain, while amylopectin is a long, branched chain of alpha-glucose.
139
Describe the structure of amylose.
A long, unbranched chain of alpha-glucose giving it a coiled structure
## Footnote
The coiled structure allows for compact storage.
140
How does the structure of amylopectin aid in glucose release?
It has side branches that allow enzymes to access glycosidic bonds easily
## Footnote
This facilitates quicker release of glucose.
141
Why is starch insoluble in water?
To prevent water from entering cells by osmosis
## Footnote
This characteristic helps maintain cell structure and prevents swelling.
142
What is the major component of plant cell walls?
Cellulose
## Footnote
Cellulose provides structural support to plant cells.
143
What type of glucose is cellulose made from?
Beta-glucose
## Footnote
Cellulose chains are formed by 1-4 glycosidic bonds of beta-glucose.
144
How are cellulose chains structured?
They are long and unbranched, joined by straight glycosidic bonds
## Footnote
This results in straight cellulose chains.
145
What are microfibrils in cellulose?
Threads formed from linked cellulose chains by hydrogen bonds
## Footnote
Microfibrils provide strength to plant cell walls.
146
What are two reasons why plant fibres are strong?
* Arrangement of cellulose microfibrils in a net-like structure
* Secondary thickening of cell walls
## Footnote
These features enhance the tensile strength of plant fibres.
147
What is secondary thickening in plant cells?
The process where structural plant cells produce a thicker secondary cell wall
## Footnote
This wall contains more lignin, which contributes to strength.
148
What is tensile strength?
The maximum weight a material can withstand before breaking
## Footnote
It is a critical measure for evaluating the strength of materials like plant fibres.
149
What is a method to measure the tensile strength of plant fibres?
Attach the fibre to a clamp stand and hang weights until it breaks
## Footnote
The mass at which the fibre breaks indicates its tensile strength.
150
What should be done to ensure accuracy in tensile strength experiments?
Repeat the experiment with different samples and keep other variables constant
## Footnote
This reduces random error and increases result precision.
151
Name two variables that should be kept constant during tensile strength testing.
* Length of the fibres
* Temperature
* Humidity
## Footnote
Keeping these variables constant ensures fair testing conditions.
152
True or False: The secondary cell wall is usually thinner than the normal cell wall.
False
## Footnote
The secondary cell wall is thicker and often contains more lignin.
153
What is sustainability?
Using resources to meet present needs without compromising future generations' ability to meet their own needs.
154
What are renewable resources?
Resources that can be used indefinitely without running out, such as plants.
155
Give an example of a sustainable practice.
Replanting trees after logging.
156
What happens when unsustainable practices are used?
Resources will eventually run out.
157
What is an example of an unsustainable practice?
Using fossil fuels to make oil-based plastics.
158
Why are plant fibres more sustainable than oil-based plastics?
Less fossil fuel is used and crops can be regrown.
159
What is a disadvantage of ropes made from plant fibres?
They are generally not as strong as ropes made of plastic.
160
What are bioplastics?
Plastics made from plant-based materials like starch.
161
Why is making plastics from starch more sustainable?
Less fossil fuel is used and the crops can be regrown.
162
What is bioethanol?
A fuel made from starch.
163
What do plants need from the soil?
Water and inorganic ions.
164
What role do magnesium ions play in plants?
They are needed for the production of chlorophyll.
165
What is the function of nitrate ions in plants?
They are needed for protein production and chlorophyll synthesis.
166
What are calcium ions required for in plants?
They are important components in plant cell walls and required for growth.
167
How can you investigate plant mineral deficiencies in a lab?
By varying the concentration of essential minerals in nutrient broths.
168
What should be done to ensure a fair experiment when investigating plant growth?
Keep all other variables the same.
169
What is the significance of using control broths in experiments?
To compare the effects of nutrient deficiencies.
170
Fill in the blank: Sustainability is all about using resources in a way that meets the needs of the present generation without _______.
messing it up for future generations.
171
True or False: Fossil fuels are considered renewable resources.
False.
172
Name two products that can be made from plants.
* Plastics
* Fuel
173
Describe four different broths needed to investigate magnesium ion and nitrate ion deficiency.
1. Broth with high magnesium and nitrate concentrations
2. Broth with medium magnesium and nitrate concentrations
3. Broth with low magnesium and nitrate concentrations
4. Control broth with all nutrients.
174
What are some properties of certain plants related to drugs?
Some plants have antimicrobial properties
## Footnote
These properties can be investigated through scientific methods.
175
What is the first step in testing the antimicrobial properties of a plant?
Prepare an agar plate of bacteria
## Footnote
Use bacteria grown in broth and spread it over the agar plate.
176
What is used to extract antimicrobial substances from plants?
Ethanol
## Footnote
Ethanol is used because the antimicrobial substances are soluble in it.
177
What is a control disc in antimicrobial testing?
A disc soaked only in ethanol
## Footnote
This ensures that the results are not due to ethanol or the paper.
178
What does a clear zone in an agar plate indicate?
The effectiveness of the plant extract's antimicrobial properties
## Footnote
A larger clear zone indicates more effective antimicrobial activity.
179
What conditions are necessary for bacterial growth in testing?
Nutrients, oxygen, appropriate temperature, and pH
## Footnote
These factors are crucial for bacteria to survive and reproduce.
180
What are aseptic techniques?
Methods used to prevent contamination of cultures by unwanted microorganisms
## Footnote
Important to avoid affecting the growth of the desired microorganism.
181
True or False: Aseptic techniques are unnecessary in microbial culture testing.
False
## Footnote
Aseptic techniques are critical to avoid contamination.
182
What historical method did William Withering use to test the effectiveness of digitalis?
Trial and error
## Footnote
He adjusted concentrations of digitalis in his 'digitalis soup' to find the right dosage.
183
What are the three phases of modern drug testing?
Phase 1, Phase 2, Phase 3
## Footnote
Each phase involves different groups and focuses on safety, efficacy, and comparison to existing treatments.
184
What is the purpose of a placebo in clinical trials?
To compare the effects of the drug against an inactive substance
## Footnote
Helps determine if the drug has actual efficacy beyond psychological effects.
185
What does a double-blind study design ensure?
Neither the patients nor the doctors know who receives the treatment or placebo
## Footnote
This reduces bias in the results of clinical trials.
186
Fill in the blank: Modern drug testing is more ______ than historic testing.
rigorous
## Footnote
It involves extensive scientific protocols and testing phases.
187
What is the effect of temperature and pH on bacterial growth?
They affect enzyme activity and metabolic processes
## Footnote
Extreme values can hinder respiration and overall growth.
188
What is the formula to calculate the area of a clear zone?
Area = πr²
## Footnote
'r' stands for radius of the clear zone.
189
What should be done with utensils used in microbial testing?
Place them in a beaker of disinfectant
## Footnote
This helps prevent contamination.
190
Why is a large sample size important in drug testing?
It increases the reliability of the results
## Footnote
Ensures that the findings are statistically significant.
