Chapter 8: Biodiversity Flashcards
Taxonomy is a field in biology which involves the classification, ________ and naming of organisms in an _____ manner.
- identification
- organized
Why is the classification and naming of organisms important?
In order to facilitate studies and discussions among scientists at an international level.
What are the six kingdoms all organisms in the world can be categorised into?
- Archaebacteria
- Eubacteria
- Protista
- Fungi
- Plantae
- Animalia
- An Evening Pigeon Flew At Plaza
What are the types of cells, number of cells and types of nutrition for the organisms from the six kingdoms?
Archaebacteria - prokaryote - Unicellular - Autotroph or Heterotroph Eubacteria - Prokaryote - Unicellular - Autotroph or Heterotroph Protista - Eukaryote - Unicellular or Multicellular - Autotroph or Heterotroph Fungi - Eukaryote - Uni or Multi - Heterotroph Plantae - Eukaryote - multi - autotroph Animalia - eukaryote - Uni or Multi - Heterotroph
What are prokaryotes and eukaryotes?
- Prokaryote is a type of cell that lacks a nucleus and membrane-enclosed organelles
- Eukaryote is a type of cell that has a nucleus and membrane-bound organelles
What are heterotroph and autotroph?
- Heterotroph is an organism that cannot synthesis its own food but obtain food molecules by eating other organisms
- Autotroph is an organism that synthesise its own food from organic materials by using light and chemical energy
Explain the characteristics and features of archaebacteria.
- pro and uni
- primitive bacteria
- cell walls with no peptidoglycan
- divided into 3 groups which are methanogen, halophile and thermophile
- Methanogen: anaerobic bacteria found in swamps and the digestive tract produces methane as a metabolic byproduct
- Halophile: in extremely high salt concentration places like the Dead Sea
- Thermophile: flourishes at an optimum temperature of 60-80 and is found in hot springs and highly acidic locations
- Ex: Sulfolobus sp. and Halobacterium
Explain the characteristics and features of eubacteria.
- pro and uni
- known as β true β bacteria
- has cell walls with peptidoglycan which is also known as murein
- cytoplasm has ribosomes and plasmids but no membrane-enclosed organelles like mitochondria
- classified according to shape
- Ex: Streptococcus pneumonia and Vibrio cholerae
Explain the characteristics and features of Protista.
- eu and uni or multi
- hetero or auto or both
- simple cell organisation without specialised tissue
- has a nucleus and membrane-enclosed organelles
- divided into 3 groups which are protozoa, algae and slime mould
- Ex. Protozoa: Euglena sp., Amoeba sp. and Paramecium sp.
- Ex. Algae: Chlamydomonas sp. and Spirogyra sp.
- Ex. slime mould: Physarum polycephalum
Explain the characteristics and features of fungi.
- eu and uni or multi
- heterotrophs
- cell wall is made up of chitin
- body made up of a thread-like network of hyphae called the mycelium
- ex: Yeast and mushroom
Explain the features of Plantae and Animalia.
Plantae - Eu and Multi - has chlorophyll - undergo sexual and asexual reproduction - Ex: seedless plants ( Fern ) and plants with seeds Animalia - eu and multi - heterotrophs - can move and reproduce sexually - invertebrate and vertebrate
The hierarchy system used in taxonomy is ______ hierarchy system. It classifies organisms according to hierarchy, starting from _____ to _____.
- Linnaeus
- species
- domain
Organisms in the same ____ have ____ characteristics. Organisms of the same ____ are capable of ________ among themselves to produce viable fertile offsprings.
- phylum
- mutual
- species
- interbreeding
What is the 8 taxonomic rank?
- domain
- kingdom
- phylum
- class
- order
- family
- genus
- species
How do we write the scientific name of an organism based on the Linnaeus binomial system?
- has two words where the first word is the name of the genus while the second name is the name of the species
- first letter is capitalised
- all scientific names must be printed in italics
- if handwritten must be underlined separately
A ______ key is a tool used by taxonomists to identity organisms based on ____ and differences. It is an ____ process. The traits chosen must be based on _____ and observable features. Overlapping traits must be ____.
- dichotomous
- similarities
- identification
- obvious
- avoided
Biodiversity can be divided into 3 types which are:
- genetic diversity
- species diversity
- ecosystem diversity
Explain genetic diversity.
- genes variation of an individual in a population and different populations of the same species
- individual isolation and adaptations cause differences in genes
- no 2 individuals of the same species are identical
- Ex: paddy where there are many varieties of cultivated rice
Explain species diversity.
- the variation and variability of organisms
- includes the total number of species and the species distribution in a community
- Ex: tropical rainforests have large species diversities with around 5-10 million of insects species
Explain ecosystem diversity.
- biotic community and ecological process in ecosystems of land and aquatic environments
- Ex: rich ecosystems can be found in the ocean and the desert
What is phylogeny?
- the evolutionary history of a species or a group of organisms that are genetically linked
In phylogenetic classification, classification is done using a _____ structure. That refers to a structure that can be observed across multiple organisms which ___ the same ______ even though the functions may ____. For example, the limbs of humans, cats, whales and bats share the same bone structure but differ greatly in ____ and ____.
- homologous
- share
- ancestor
- differ
- size
- length
Microorganisms can be divided into 5 types which are:
- bacteria
- protozoa
- algae
- fungi
- virus
Explain the characteristics of bacteria.
- prokaryote
- genetic materials in the form of chromosomal threads ( DNA ) free-floating inside the cytoplasm known as the nucleoid
- some have plasmid which carries extra genes
- range from 1 to 10 micrometer
- can exist as a single cell, diploid, filaments and chains
- exist in shapes like coccus, vibrio, bacillus and spirillum
- Ex: Lactobacillus sp. and Streptococcus sp.
Explain the characteristics of protozoa.
- animal-like unicellular microorganisms
- move using pseudopodia, cilia or flagellum
- found in aquatic habitats
- hetero or auto such as Euglena sp. which is an autotrophic protozoan
- can be free-living or parasitic
Explain the characteristics of algae.
- uni and multi
- move in water with flagellum
- have chloroplasts and are autotrophic
- live in ponds, lakes and ocean
Explain the characteristics of fungi.
- no chlorophyll and are heterotrophs, either parasites or saprophytic
- no roots or stems
- cell walls by chitin
- exist in the form of mycelium which is a thread-like network called hyphae
- uni or multi
- found in dark or moist places
Explain the characteristics of viruses.
- not included in any kingdoms because they are not cellular
- does not carry out life processes
- reproduce by injecting their genetic materials into host cells
- made up of nucleic acids such as DNA or RNA and capsids from protein
- too small in size ( 20 - 400 micrometer ) and can only be seen through an electron microscope
- Ex: tobacco mosaic virus, T4 Bacteriophage and HIV.
Plants require nitrogen to _____ protein and this is obtained from the soil in the form of _____ ions and ____ ions. Thus, explain the process in the nitrogen cycle before the conversion into ions.
- synthesise
- ammonium
- nitrate
- nitrogen-fixing bacteria lives in the root nodules of legumes like Rhizobium sp. and free-living nitrogen-fixing bacteria such as Azotobacter sp. in the soil change it to ammonium ions via the nitrogen-fixing process
- lightning oxidises nitrogen to NO2 via the nitrogen-fixing process which dissolves in rainwater to produce nitrous acid and nitric acid
- fertilisers provide ammonium and nitrates in soil
- decomposition is carried out by bacteria and saprophytic fungi where body tissue breaks down into ammonium via ammonification
Explain the nitrogen-fixing process from the conversion of ions.
- ammonium ions are converted into nitrite ions via nitrification by the nitrifying bacteria Nitrosomonas sp.
- nitrite ions then are converted into nitrate ions by Nitrobacter sp.
- nitrates will then be absorbed by plants to syntheise proteins
- the plants are eaten by animals and is transferred into animalsβ body tissues
- denitrifying bacteria convert nitrates in the soil into nitrogen gas through denitrification
What are the 4 roles of microorganisms?
- producers
- decomposers
- parasites
- symbionts
Explain microorganisms as producers and parasites.
Producers
- phytoplankton floating on the surface of aquatic surfaces
- Ex: green algae, blue-green algae ( cyanobacteria ), dinoflagellates and diatoms
- can undergo photosynthesis
Parasites
- parasite benefits from the relationship
- try not to kill their hosts
- Ex: Plasmodium sp. is a protozoa that lives inside the female Anopheles mosquito and transmits malaria into the blood circulatory system
Explain microorganisms as decomposers.
- saprophytic fungi and bacteria decompose organic materials and are known as decomposers
- break down complex organic materials into simple compounds such as ammonium
- secrete digestive enzymes into the decaying materials and absorb the products
- the products contain carbon, nitrogen and sulphur
Explain microorganisms as symbionts.
- an organism that has a close relationship with another organism
- two types which are ectosymbionts and endosymbionts
- ectosymbionts live outside the host cell like Ectomycorrhiza, a fungi which lives around plant roots
- endosymbionts live inside the host cells like Protozoa Trichonympha sp. which lives in the alimentary canals of termites
A pathogen is an organism which causes _____. For example, viruses, _____, protozoa and ____.
Vectors are organisms that ____ pathogens and cause ____ diseases.
- diseases
- bacteria
- fungi
- transmit
- certain
What are the examples of disease vectors?
- Vibrio cholerae is spread through flies ( cholera )
- dengue virus is transmitted through Aedes aegypti mosquito bites
- Salmonella typhi bacteria are transmitted through food and water that are contaminated by cockroaches
What are the viruses, examples of diseases and the symptoms of the diseases it causes?
- Virus - Hepatitis B - inflammation, swollen chest, yellowish skin and may cause fatalities
- Bacteria - Tuberculosis - weight loss, coughing blood and shortness of breath
- Protozoa - dysentery - stomach ache, diarrhoea and vomit
- Fungi - Tinea versicolour - whitish or pinkish patches on skin
