Mycorrhizae are useful for plants because they
fix atmospheric nitrogen.
enhance absorption of nutrients from the soil.
kill insects and pathogen.
provide resistance against abiotic stresses.
Correct Answer :
B. enhance absorption of nutrients from the soil.
Mycorrhizae is symbiotic association between fungi and roots of higher plants, e.g., in the roots of Pinus. This association provides the fungus with a renewable source of food through access to fixed carbon (sugars) from the plant photosynthate.
Related Questions
Choose the correct names of the different bacteria given below according to their shapes.
A – Cocci, B – Bacilli, C – Spirilla, D – Vibrio
A – Bacilli, B – Cocci, C – Spirilla, D – Vibrio
A – Spirilla, B – Bacilli, C – Cocci, D – Vibrio
A – Spirilla, B – Vibrio, C – Cocci, D – Bacilli
Which of the following statement(s) is/are correct about class basidiomycetes ?
(i) They are commonly known as imperfect fungi because only the asexual or vegetative phases of these fungi are known.
(ii) They grow in soil, on logs and tree stumps and in living plant bodies as parasites, e.g., rusts and smuts.
(iii) The mycelium is branched and septate.
(iv) Some common members are Agaricus, Ustilago and Puccinia.
Only (i)
Both (ii) and (iii)
(ii), (iii) and (iv)
All of these
Read the given statements and answer the question.
(i) It includes unicellular as well as multicellular fungi.
(ii) In multicellular forms hyphae are branched and septate.
(iii) Conidiophore produces conidia (spores) exogenously in chain.
(iv) Sexual spores are ascospores produced endogenously in chain.
(v) Fruiting body is called ascocarp.
Identify the correct class of fungi which have all the given characteristics.
Phycomycetes
Sac fungi
Club fungi
Fungi imperfecti
Which group of fungi is commonly known as imperfect fungi ?
Phycomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes
Lichens indicate SO2 pollution because they
show association between algae and fungi.
grow faster than others.
are sensitive to SO2.
flourish in SO2 rich environment.
The bacteria which oxidize various inorganic substances and use the released energy for their ATP production are called _______________.
Archaebacteria
Heterotrophic bacteria
Photosynthetic autotrophic bacteria
Chemosynthetic autotrophic bacteria
Bladderwort and Venus fly trap are examples of
insectivorous plants
parasitic plants
N2 rich plants
aquatic plants
The given characters are seen in which of the following group?
(i) Unicellular, colonial, filamentous, marine or terrestrial forms.
(ii) The colonies are surrounded by a gelatinous sheath.
(iii) Some can fix atmospheric nitrogen in specialized cells called heterocysts.
(iv) They often form blooms in water bodies.
Archaebacteria
Cyanobacteria
Chrysophytes
Dinoflagellates
A virus can be considered a living organism because it
responds to touch stimulus
respires
reproduces (inside the host)
can cause disease
Match column I (Kingdom) with column II (Class) and select the correct options
| Column-I | Column-II |
|---|---|
| (Kingdom) | (Class) |
| A. Plantae | I. Archaebacteria |
| B. Fungi | II. Euglenoids |
| C. Protista | III. Phycomycetes |
| D. Monera | IV. Algae |
A IV, B III, C II, D I
A I, B II, C III, D IV
A III, B IV, C II, D I
A IV, B II, C III, D I
The given statements are some characters of a particular group of Kingdom protista.
(i) Most of them are fresh water organisms found in standing water.
(ii) They have a protein rich layer (called pellicle) which makes their body flexible.
(iii) They have two flagella, a short and a long one.
(iv) Though they are photosynthetic in the presence of sunlight, but in the absence of sunlight they behave like heterotrophs by predating on other smaller organisms.
Identify the correct group on the basis of these characters.
Protozoans
Chrysophytes
Slime moulds
Euglenoids
Refer the given figure of bacteria cell and Nostoc and choose the option which shows correct label for the structure marked as A, B, C, D and E ?
A – Cell wall, B – Cell membrane, C – Heterocyst, D – DNA, E – Mucilagenous sheath
A – Cell wall, B – Cell membrane, C – DNA, D – Heterocyst, E – Mucilagenous sheath
A – Mucilagenous sheath, B – Cell membrane, C – DNA, D – Heterocyst, E – Cell wall
A – Cell membrane, B – Cell wall, C – DNA, D – Heterocyst, E – Mucilagenous sheath
Plasmogamy is the fusion of
two haploid cells including their nuclei.
two haploid cells without nuclear fusion.
sperm and egg.
sperm and two polar nuclei.
The subunit of capsid is called
core
nucleotide
amino acid
capsomere
Bacteria were regarded to be plants because
some of them are green in colour.
they are present every where.
some of them cannot move.
they have a rigid cell wall.
Bacteria are found to be primitive organisms because they
are small, microscopic which are not seen with naked eye.
cause serious diseases to human being, domesticated animals and crop plants.
produce endospores which are very resistant to adverse conditions.
possess incipient nucleus and show amitotic division.
How many organisms in the list given below are autotrophs? Lactobacillus, Nostoc, Chara, Nitrosomonas, Nitrobacter, Streptomyces, Saccharomyces, Trypanosomes, Porphyra, Wolffia
Four
Five
Six
Three
Bacteria lack alternation of generation because there is
neither syngamy nor reduction division.
no distinct chromosomes.
no conjugation.
no exchange of genetic material.
Ustilago causes plant diseases (called smuts) because
they parasitize on cereals.
they lack mycelium.
they develop sooty masses of spores.
their affected parts becomes completely black.
Which of the following kingdom does not have nuclear membrane ?
Protista
Fungi
Monera
Plantae
Which of the following statements regarding cyanobacteria is incorrect?
It is also called blue green algae.
They are chemosynthetic autotrophs.
It forms blooms in polluted water bodies.
It is unicellular, colonial or filamentous, marine or terrestrial bacteria.
Match column I (containing fungus name) with column II (common name) and choose the correct options.
| Column-I | Column-II |
|---|---|
| (Fungus name) | (Commonly called) |
| A. Puccinia | I. Yeast |
| B. Ustilago | II. Mushroom |
| C. Agaricus | III. Smut fungus |
| D. Saccharomyces | IV. Rust fungus |
A I, B II, C III, D IV
A II, B III, C IV, D I
A III, B IV, C I, D II
A IV, B III, C II, D I
Assume that two normal hyphal cells of different fungal mating types unite. After a period of time, the cell between these cells will dissolve producing a
mycelium
fruiting body
zygote
dikaryotic cell, which is also heterokaryotic
Which of the following is not a viral disease ?
AIDS and mumps
Small pox and herpes
Influenza
Cholera
Why food can be kept for a longer time in cold house than in normal conditions ? Because,
insect cannot enter.
bacterial multiplication stops.
bacterial multiplication is reduced.
there is plasmolysis at low temperature.
Which of the following statement is/ are correct for bacteria ?
They are the members of the kingdom monera.
They live in extreme habitats such as hot springs, deserts, snow and deep oceans.
They show the most extensive metabolic diversity.
All of the above
Protozons are not included in kingdom animalia because they are
mostly asymmetrical.
unicellular eukaryotes.
heterotrophic in nature.
multicellular prokaryotes.
Which statement is not correct for viruses ?
Viruses are obligate parasites.
Viruses can multiply only when they are inside the living cells.
Viruses cannot pass through bacterial filters.
Viruses are made up of protein and DNA or RNA (never both DNA and RNA).
Match the terms given in column-I with their examples given in column-II and choose the correct option
| Column-I | Column-II |
|---|---|
| (Terms) | (Examples) |
| A. Ascus | I. Spirulina |
| B. Basidium | II. Penicillium |
| C. Protista | III. Agaricus |
| D. Cyanobacteria | IV. Euglena |
| E. Animalia | V. Sponges |
A II, B III, C IV, D V, E I
A I, B II, C III, D V, E IV
A II, B V, C III, D I, E IV
A II, B III, C IV, D I, E V
Which of the following groups of protozoan is not correctly matched with its feature?
Amoeboid - Marine forms have silica shells on their surface.
Flagellated - Either free living or parasitic.
Ciliated - Actively moving organisms due to presence of cilia.
Sporozoans - Move and capture their prey with the help of false feet.