chapter 2 bio Flashcards
The five-kingdom classification was proposed by
R.H.Whittaker.
R.H.Whittaker classified them on?
cell structure, thallus organization, reproduction, mode of nutrition,
name the 5 kingdoms
Kingdom Monera
Kingdom Protista
Kingdom Fungi
Kingdom Plantae
Kingdom Animalia.
Why are cyanobacteria used in agricultural fields for crop improvement?
have the ability to fix atmospheric nitrogen
Give an example of insectivorous plants.
Venus flytrap
pitcher plants,
butterworts
sundews
What similarities do a virus and non-living objects share?
A virus is considered living inside the host but non-living when outside the host. This is because:
1- Inert nature.
2- Inability to reproduce.
3- No cellular organization.
4- It cannot grow and divide
Why do polluted water bodies have an abundance of Nostoc and Oscillatoria?
The nutrients present in the polluted water bodies enhance the growth of algal plants such as Nostoc and Oscillatoria.
Name the eukaryotic kingdoms in the five-kingdom classification proposed by Whittaker.
Protista
Fungi
Animalia
Plantae
What is the nature of the cell wall in diatoms?
The cell wall of diatoms forms two thin overlapping cells. It is made up of silica.
ho proposed the five-kingdom classification
Robert Whittaker
What is the difference between a virus and a viroid?
A virus contains DNA or RNA as the genetic material and a protein coat whereas the viroids do not have a protein coat but RNA as genetic materia
State the uses of heterotrophic bacteria which are economically important.
They maintain the fertility of the soil by nitrogen fixation, ammonification and nitrification. Eg., Rhizobium
The milk products such as cheese, curd are obtained by bacteria
State the uses of archaebacteria which are economically important
Biogas is produced by methanogens from animal dung
The chemosynthetic bacteria are autotrophic or heterotrophic?
Autotrophs
Give an example of parasitic plants.
The Corpse Flower, birds’ nest orchid and dodder
What is diatomaceous earth?
The accumulation of large deposits of diatoms that forms a covering of silica extending over several 100m for billions of years.
Why are diatoms referred to as ‘pearls of the ocean’?
Diatoms are the main producers in the ocean. They prepare food for themselves as well as other life forms in the ocean. Their body is made up of siliceous shell known as a frustule.
Explain the myth of ‘fairy rings’ created by the mushrooms after heavy rains in the forest
The mycelium of the mushroom absorbs nutrients from the soil. The nutrients in the centre get exhausted and grow in diameter thereby forming a circle. These rings are the fruiting bodies of the fungus and are known as ‘fairy ring
Why is Neurospora an important genetic tool?
Neurospora can be grown easily under laboratory conditions by providing organic salts, carbohydrates and vitamin. Under X-ray treatments, mutations can be introduced easily in the Neurospora cells and meiotic division is easily visible.
What is the role of fungi our daily lives?
1- They provide resistance against pests.
2- Some fungi possess the soil binding capacity and make the soil good for cultivation
3- highly rich in nutrients and are used as food.
4- Fungi are used in alcohol and yeast preparation
What features of Trypanosoma make it fall under the kingdom Protista?
1-They are unicellular.
2-The nucleus is centrally located and the nucleus contains an endosome.
3- Reserve food material is granulated.
4- They reproduce asexually by binary fissio
The ascomycetes produce fruiting bodies like apothecium, perithecium, or cleistothecium. What are the differences between these three fruiting bodies?
Apothecium : It is a cup-shaped structure. It is the ascigerous fruitification of lichens. Eg., Peziza
Perithecium : It is a flask-shaped structure. Eg., Neurospora
Cleistothecium :It is a closed ascocarp. Eg., Penicillin
Cyanobacteria and heterotrophic bacteria are very different from each other but fall under eubacteria of kingdom Monera. Is this type of grouping justified
They do not possess a well-defined nucleus.
DNA lies freely in the cytoplasm.
The ribosomes are 70S type.
The nucleus does not have a nucleolus and a nuclear membrane
What are Parasitic plants?
Plants which depend on other plants and animals for their nutrition are known as parasitic plants. Cuscuta and Cassytha are examples of parasitic plants.
What do you understand by ‘phycobiont’ and ‘mycobiont’?
The algal component of the lichens is known as phycobiont, while the fungal component is known as mycobiont. Both the algae and the fungi live in symbiotic association with each other. The algae prepare food for the fungi and the fungi, in turn, provides shelter and absorbs nutrients from the soil.
Are viruses living or non-living?
Viruses are known as the connecting link between the living and the non-living. The features that classify them as living and non-living are mentioned below:
Living:
1- They possess a non-cellular organization.
2-They are inactive outside the body of a host.
3- Lack of respiration
4- The absence of cell metabolism.
5- They can be crystallized and precipitated.
—Non-living:
1- They possess genetic material.
2- They can undergo mutation.
3- They can grow and multiply when inside the host.
4- They are obligate parasites and attack specific hosts.
What are the Insectivorous plants?
Plants that derive their nutrients from trapping and consuming insects and other arthropods or protozoans
Acidic bogs are the best examples
Name a few plants that are partially heterotrophic.
Venus fly trap, bladderwort, and sundew plant.
Give an account of the asexual reproduction by spores in algae.
1-Zoospores
2-Aplanospores
3-Tetraspores
4-Akinetes
5-Exospores
6-Endospores
explain zoospores
Motile, naked spores with two, four or many flagella
ex:Chlamydomonas and Oedogonium
explain Aplanospores
1- hese spores are non-motile.
2- They may be formed either singly or by the division of protoplast to form several aplanospores
3- these are formed inside the sporangium during unfavourable conditions
explain Tetraspores-
Tetraspores are produced by diploid plants of some algae. These are a special type of haploid aplanospores formed within tetrasporangium
Akinetes-
These are thick-walled spore-like structures with abundant food reserves. They can survive under unfavourable conditions.
explain Exospores-
These are separated from the mother cell by the formation of the septum. They are formed near the end of the mother cell. Eg., Chamaesiphon
explain Endospores-
The mother protoplast divides and forms the endospores. They are also known as conidia or gonidia. These are formed to survive under unfavourable conditions. Eg., Dermocarpa
What are the characteristic features of euglenoids
hey are unicellular protists, commonly found in freshwater.
The cell membrane is rich in proteins and is known as a pellicle.
Two flagella are present on the anterior end of the body.
They possess a small light-sensitive eyespot.
They are autotrophic because of the presence of photosynthetic pigment chlorophyll. However, in the absence of light, they behave as heterotrophs.
They are known as the connecting-link between plants and animals because they possess features common to both plants and animals.
How is ‘peat’ naturally formed
1- Peat is an organic fuel that consists of spongy material formed by the partial decomposition of organic matter in wetlands 2- The warm and moist climatic conditions facilitate the development of peat.
3- The main producers of peat Sphagnum mostly occur in bogs.
4- This plant gets accumulated over a period of time and gets hardened thereby converting into peat.
5- It is used in the production of ethyl alcohol, tar, ammonia, etc. 6- It is also used for the purpose of covering roots during transportation.
. What are the advantages of five kingdom classification?
1- This system of classification is more scientific, accurate and natural.
2- all living organisms are classified into different groups based on their similarities.
3- The five-kingdom classification helps to learn more in detail about the phylogeny and evolutionary history of organisms
explain types of bacteria based on shapes
1- Rod-shaped bacteria also called the bacilli.
2- Spiral shaped bacteria also called the spirilla.
3- Comma shaped bacteria also called the vibrios.
4- Spherical shaped bacteria also called the cocci.
5- Corkscrew-shaped bacteria also called the spirochaetes
explain types of bacteria based on composition of cell wall
1- Gram-positive bacteria.
2- Gram-negative bacteria.
explain types of bacteria based on their mode of respiration
- Aerobic bacteria or Aerobe
- Anaerobic bacteria or Anaerobe
Based on the mode of nutrition
Autotrophic Bacteria
Heterotrophic Bacteria
The common name of pea is simpler than its botanical (scientific) name Pisum sativum. Why then is the simpler common name not used instead of the complex scientific/botanical name in biology?
It is easier to remember a standard scientific name as compared to so many names. instead of using simple common names, it is preferred to use scientific names which may appear complicated but universally accepted
Give scientific name of species of fungus:-
(a) Produces a plant disease.
(b) Is edible
(c) A source of antibiotic
(d) Used in manufacture of ethanol
a- Puccinia recondita
b- agaricus benesii
c-Penicillium chrysogenum
d-Saccharomyces cerevisiae
what are imperfect fungi ?
asexually reproducing fungi belonging ti deuteromycites
How many basidiospores are formed after Karyogamy and meiosis?
4
What is plasmogamy?
Fusion of protoplasms between two motile or non-motile gametes.
What do you mean by mycorrhiza?
Mycorrhiza is a symbiotic association between fungi with roots of higher plants.
How does the spore of slime molds disperse?
By air currents
Name the protein-rich layer found in Euglenoids.
Pellicle.
Give an example of red dinoflagellates?
Gonyaulax.
Who is known as ‘Producers of the oceans’?
Diatoms
.
Name the organism responsible for algal bloom?
Blue-green algae
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