Free Biological Molecules MCQs with Answers
1,790 Biological Molecules MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The chapter covers water's polarity and biological roles, carbohydrates, lipids, proteins and nucleic acids, including their monomers, bonds, structures and functions. It also distinguishes RNA from DNA and explains conjugated molecules such as glycoproteins, glycolipids and nucleoproteins, which combine organic molecules with a non-protein component.
Last updated
1,790 questions · page 12 of 90
- A. Deuteromycota
- B. Basidiomycota
- C. Zygomycota
- D. All of these
Explanation: Basidiomycota commonly maintain dikaryotic hyphae, in which each cell contains two genetically different haploid nuclei, for a prolonged…
Correct answer: Basidiomycota- A. Septate
- B. Perforated hyphae
- C. Aseptate
- D. Uninucleate hyphae
Explanation: Coenocytic hyphae lack cross-walls or septa, so they form a continuous multinucleate tube and are therefore called aseptate hyphae.
Correct answer: Aseptate- A. Pilobolus
- B. Penicillium
- C. Neurospora
- D. Rhizopus
Explanation: Rhizopus is commonly called black bread mold because it produces black sporangia on decaying bread and other organic material.
Correct answer: Rhizopus- A. Cyanobacteria
- B. Blue green algae
- C. Bacteria
- D. Virus
Explanation: Bacteria, like fungi, are major decomposers that secrete enzymes into dead material and absorb the soluble products, returning nutrients…
Correct answer: Bacteria- A. Formation of sporangiophore via germination of zygospore.
- B. Formation of spores in sporangia
- C. Fusion of two hyphae
- D. Formation of Zygote by fusion of gametangia.
Explanation: In Rhizopus, the zygospore is diploid and undergoes meiosis when it germinates, producing haploid spores in a newly formed sporangium.
Correct answer: Formation of sporangiophore via germination of zygospore.- A. Plantae
- B. Animalia
- C. Protista
- D. Fungi
Explanation: In the traditional two-kingdom system, fungi were grouped with plants in Plantae because both are generally nonmotile and possess cell…
Correct answer: Plantae- A. Algae
- B. Bacteria
- C. Fungi
- D. Embryophata
Explanation: Fungi are called the kingdom of recyclers because their extracellular enzymes decompose dead organic matter and release minerals back into…
Correct answer: Fungi- A. Zygomycota
- B. Ascomycota
- C. Basidiomycota
- D. Deuteromycota
Explanation: Ascomycota is generally regarded in introductory biology as the largest fungal group, containing numerous yeasts, molds, and cup fungi…
Correct answer: Ascomycota- A. Mycorrizael association
- B. Endomycorrhizae
- C. Ectomycorrhizae
- D. Lichen
Explanation: Endomycorrhizae grow into the outer root cells and form coils, swellings, or arbuscule-like branches while their hyphae also extend into…
Correct answer: Endomycorrhizae- A. 30%
- B. 40%
- C. 50%
- D. 60%
Explanation: About 50% of known Ascomycota species are associated with lichens, in which the fungus receives organic nutrients and the photosynthetic…
Correct answer: 50%- A. Stem like
- B. Branching
- C. Leaf like
- D. Crust like
Explanation: Foliose lichens have broad, flattened, leaf-like lobes that are loosely attached to the surface on which they grow.
Correct answer: Leaf like- A. Autotrophs
- B. Roots of vascular plants
- C. Green algae and cyanobacterium
- D. Leguminous plants
Explanation: A lichen is a mutualistic association between a fungus and a photosynthetic partner, usually a green alga or cyanobacterium.
Correct answer: Green algae and cyanobacterium- A. Pin warms
- B. Tape worms
- C. Round worms
- D. Platehelminthes
Explanation: Some oyster mushrooms trap and digest nematodes, which are roundworms, using specialized hyphae or adhesive structures.
Correct answer: Round worms- A. Saprotrophs
- B. Parasitic
- C. Predators
- D. Mutualistics
Explanation: Penicillium is mainly saprotrophic: it secretes digestive enzymes onto dead organic matter and absorbs the soluble nutrients.
Correct answer: Saprotrophs- A. Parasitic fungi
- B. Obligate parasitic fungi
- C. Facultative parasitic fungi
- D. All of these
Explanation: Obligate parasitic fungi must obtain nutrients from a living host and cannot normally complete growth on an artificial defined culture…
Correct answer: Obligate parasitic fungi- A. Spores
- B. Conidia
- C. Budding
- D. Fragmentation
Explanation: Penicillium reproduces asexually by producing conidia, which are nonmotile spores formed externally on brush-like conidiophores.
Correct answer: Conidia- A. Rhizodis
- B. Haustoria
- C. Hyphae
- D. Constricting rings
Explanation: Rhizoids are root-like hyphal structures that anchor saprotrophic fungi and help absorb nutrients from the substrate; option a is…
Correct answer: Rhizodis- A. Anaerobic
- B. Nitrogen fixing
- C. Nitrifying
- D. Ammonifying
Explanation: Root nodules of leguminous plants contain Rhizobium, which converts atmospheric nitrogen into usable nitrogen compounds through nitrogen…
Correct answer: Nitrogen fixing- A. Corn
- B. Tomato
- C. Dodder
- D. Wheat
Explanation: Puccinia is the rust fungus responsible for diseases such as wheat rust, which damages wheat plants and reduces yield.
Correct answer: Wheat- A. Potassium
- B. Magnesium
- C. Phosphorus
- D. Iron.
Explanation: Phosphorus is needed for ATP, nucleic acids and membrane phospholipids, and its deficiency particularly restricts root growth and…
Correct answer: Phosphorus