- Which of the following statements is true for viruses?
a) They are cellular organisms
b) They can reproduce outside a host
c) They have either DNA or RNA as genetic material
d) They have both DNA and RNA
Answer: c) They have either DNA or RNA as genetic material
Explanation:
Viruses contain either DNA or RNA, but not both, as their genetic material. They can only replicate inside a host cell.
- The ability to fix atmospheric nitrogen is a characteristic of:
a) Yeasts
b) Cyanobacteria
c) Viruses
d) Amoeba
Answer: b) Cyanobacteria
Explanation:
Cyanobacteria (e.g., Anabaena, Nostoc) are able to fix atmospheric nitrogen into ammonia, which can be utilized by plants.
- Which of the following structures are used by paramecia for movement?
a) Flagella
b) Cilia
c) Pseudopodia
d) Tentacles
Answer: b) Cilia
Explanation:
Paramecia move using cilia, small hair-like structures that beat rhythmically to propel the organism.
- Which group of organisms is referred to as ‘naked seed plants’?
a) Bryophytes
b) Pteridophytes
c) Gymnosperms
d) Angiosperms
Answer: c) Gymnosperms
Explanation:
Gymnosperms are seed-producing plants where the seeds are exposed (naked) and not enclosed within a fruit.
- The term ‘biodiversity’ refers to:
a) Variability among living organisms
b) The extinction of species
c) The cultivation of various crops
d) Genetic engineering
Answer: a) Variability among living organisms
Explanation:
Biodiversity refers to the variety and variability of life on Earth, including species diversity, genetic diversity, and ecosystem diversity.
- Which of the following kingdoms includes heterotrophic organisms that digest their food externally and absorb the nutrients?
a) Protista
b) Fungi
c) Plantae
d) Animalia
Answer: b) Fungi
Explanation:
Fungi digest their food outside their bodies by secreting enzymes, and then absorb the nutrients through their cell walls.
- Which of the following statements is incorrect about slime molds?
a) They belong to the kingdom Fungi
b) They are saprophytic
c) They have a plasmodial stage in their life cycle
d) They reproduce by spores
Answer: a) They belong to the kingdom Fungi
Explanation:
Slime molds belong to the kingdom Protista, not Fungi, though they share some characteristics like spore reproduction.
- Which of the following belongs to the group Archaebacteria?
a) Mycoplasma
b) Methanogens
c) Cyanobacteria
d) Spirochetes
Answer: b) Methanogens
Explanation:
Methanogens are a type of Archaebacteria found in extreme environments like swamps, and they produce methane as a metabolic byproduct.
- Which of the following is absent in a bacterial cell?
a) Plasma membrane
b) Ribosomes
c) Mitochondria
d) Cytoplasm
Answer: c) Mitochondria
Explanation:
Bacterial cells lack membrane-bound organelles like mitochondria. Their energy-producing processes occur in the plasma membrane.
- In which of the following organisms would you expect to find pseudopodia?
a) Paramecium
b) Amoeba
c) Plasmodium
d) Euglena
Answer: b) Amoeba
Explanation:
Amoeba use pseudopodia, which are temporary projections of the cytoplasm, to move and capture food.
Leave a comment