Chapter 18- Classification, biodiversity and conservation Flashcards
Define biological species
- A group of organisms with similar morphology and physiology, which can breed together to produce fertile offspring and are reproductively isolated from other species
Define ecological species
- A population of individuals of the same species living in the same area at the same time.
define population
- All of the organisms of the same species present in the same place and at the same time that can interbreed with one another.
State the Taxonomic rank
- Domain
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
What are the 3 main Domains
- Bacteria
- Archaea
- Eukarya
Describe the Domain Bacteria
- Prokaryotic
- small in size
- No nucleus
- No membrane-bound cells
- ribosomes 70S
- Cell walls are always present with peptidoglycan
- Cells divide by binary fission
- DNA is circular
Describe the Domain Archaea
- Prokaryotic
- size similar to bacteria
- have a similar metabolism to bacteria
- have a similar transcription to that of eukaryotes
- ribosomes are 70S
- membrane lipids
- cell walls are always present
- Cells divide by binary fission
Describe the Domain Eukarya
- All cells have nuclei and are membrane-bound
- DNA in the nucleus with chromosomes
- Ribosomes are 80S in the cytosol
- Cells divide by mitosis
- cell walls present in some eukaryotes
- reproduce either sexually or asexually
State the 4 Kingdoms
- Protoctista
- Fungi
- Plantae
- Animalia
Describe the features of protoctists
- Eukaryotic
- Mostly single-celled
- Some cells don’t have cell walls (protozoa)
- Some cells have cellulose cell walls and chloroplasts (Algae)
Describe the features of fungi
- Eukaryotic
- Do not carry out photosynthesis
- They use organic compounds made by other organisms as their source of energy (Heterotrophic nutrition)
- Reproduce by means of spores
- Cell walls made of chitin
- Never have cilia
Describe the features of plants
- Multicellular eukaryotes
- Some cells contain chloroplasts
- Autotrophic nutrition
- Cells have large permanent vacuoles
- Cell walls made of cellulose
Describe the features of Animalia
- Multicellular eukaryotes
- No chloroplasts and cannot photosynthesis
- Cell vacuoles are small and temporary
- Heterotrophic nutrition
- No cell walls
- Communication by the nervous system
Describe the features of Viruses
- Viruses are not in the 3-domain classification as they are acellular
- The taxonomic system for classifying viruses is based on the type of nucleic acid they contain
- Both DNA and RNA can be either single or double-stranded
Define biodiversity
- The degree of variation of life forms in an ecosystem
What are the 3 levels that biodiversity can be assessed at
- > The number and range of ecosystems and habitats
- > Number of different species in the ecosystem and their relative abundance
- > The genetic variation
Define an ecosystem
a relatively self-contained interacting community of organisms and the environment in which they live and interact in
Define a community
All of the living organisms of all species that are found in a particular ecosystem at a particular time
Define a habitat
The place where a species lives within an ecosystem
Define a niche
- The role of an organism in an ecosystem
Define Species diversity
- This includes a measure of the evenness of the abundance of different species
What is a strength of species diversity
- They tend to be more stable and have greater resilience because they are able to resist changes in environmental factors
Define Genetic diversity
- All the alleles of all the genes in the genome of a species
Why is genetic diversity important
- provides populations the ability to adapt to changes in biotic and abiotic factors
- Reduces vulnerability to diseases
- Allow species to undergo natural selection and evolution
- Can contribute to the ecosystem functions
- Can help endangered species with breeding programs
When is it best to use random sampling
- When there is no clear pattern
- Reduces bias
- Improves reliability of the results
- Supports objectivity
Describe random sampling using quadrats
1- Decide on a suitable size for the quadrat and how many samples to take
2- Mark out an area with measuring tapes and use a random number generator
3- Record whether the species was present in each quadrat that you analyze
Define Species density
- the measure of how many individuals there are per unit area
Describe the mark-release-recapture method (Lincoln Index)
- Catch several individuals as much as possible and mark them in a way that will not affect its future chance of survival
- The marked individuals are counted and returned to their habitat
- When enough time has lapsed for mixing, another large sample is captured
- The number of marked and unmarked are counted and the proportion of marked to unmarked is calculated to estimate the total number of the population
what are the symbols for calculating the estimated number in a population:
N= population estimate
n1=Number of marked individuals released
n2= number of individuals both marked and unmarked that are captured
m2= number of marked individuals recaptured
What an advantage and one disadvantage of using the Simpsons index
+ You do not need to identify all organisms present to the level of species with their scientific names
-Comparisons using the index should only be between similar communities and organisms
in the Simpsons index of diversity, define n and N
n- The total number of organisms of a particular species
N- The total number of organisms of all species
Describe when systematic sampling can be used
- When you want to investigate how species are distributed in an area where the physical conditions change
Such conditions are: - altitude
- soil
- pH
What is a transect
- This is a line marked by a tape measure along which samples are taken by noting the species
- This can be done at equal distances making it a LINE transect
- It can also be done by placing quadrants at regular intervals making it a BELT transect
When can you use the Pearsons linear correlation and when can you use Spearman’s rank correlation
Pearsons:
- A linear correlation
- quantitative data measurements have been collected
- When the data is normally distributed
Spearman’s:
- quantitative data is not normally distributed
- data is not in a linear correlation
- instead of quantitative data being collected, an abundance scale was used instead
what are the reasons for the extinction of animals
- Humans- By destroying their habitats by draining wetlands, cutting down rainforests, and pollution. There’s also hunting and poaching that can lead to extinction
- Climate change- increase in sea level, ocean temps increase and ocean acidity
- Introduction of new species to a habitat
- Competition for resources, water or food
State the reasons for maintaining biodiversity
- Moral and ethical reasons
- Ecological reasons such as:
> The unbalanced results may change conditions in the community
> Change in food web flow - Economic reasons such as:
> Many of the drugs we use originate from living organisms
> Ecotourism is a source of income for some countries - Aesthetic reasons: maintaining the beauty of the natural world
- Agricultural reasons:
> To maintain genetic diversity in crop plants - Environmental reasons:
> Forests absorb the CO2 in the atmosphere
> Transpiration of plants contributes to the water cycle
> Species of fungi or bacteria help recycle elements such as nitrogen
How can National parks protect endangered species
- They keep restrictions on human activities
- Tourism brings money to pay for the maintenance of the parks and also helps to inform people about how conservation takes place which raises awareness
- Provide the animals with resources, protection and careful management
How can zoos protect endangered species
- Provide protection with successful captive breeding programmes however there’s the risk of inbreeding or animals refusing to breed in captivity
- Zoos play an important role in research
How can Assisted reproduction protect endangered species
- By collecting the semen of these animals and kept frozen in a sperm bank
- Through artificial insemination, and the process of embryo transfer
- IVF can be carried out where the oocytes are kept in a culture and later mixed with semen to result into zygotes to form embryos
How can Botanic gardens protect endangered plant species
- Protect them from environmental degradation and climate change
- Research methods of reproduction and growth
- Research conservation methods so plants can be introduced to new habitats if the original one is destroyed
- Reintroduce species to habitats where they have become rare
- Educating the public
What is an alien species
- A species that has moved into a new ecosystem where it was previously unknown
Why should scientists control alien species
- May become successful predators in the new habitat
- May occupy the same niche as some organisms which push them into extinction
- They may also introduce diseases that spread to similar organisms
How does the Convention on International Trade in Endangered Species of Wild Flor and Fauna (CITES) conserve species
- CITES considers the evidence and assigns them to one of their 3 Appendices
- Species listed on the CITES appendices are reviewed by experts committees
How does the International Union for Conservation of Nature (ICUN) conserve species
- They IUCN Red List of Threatened Species evaluates the status of many of the world’s species of animals and plants.
- Scientists monitor populations and evaluate the risk of species becoming extinct.
- They then apply certain criteria to the information that they have available before assigning each species to different categories. This information is available to governments, environmental scientists and conservationists
