Botany MCQs
Topic Notes: Botany
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
121
What are the primary classifications or groups associated with slime molds?
Answer:
a and b both
Slime molds are a diverse group of organisms that can be categorized based on their life stages and cellular organization. The two main groups are cellular slime molds, which often exist as individual amoeboid cells that aggregate into colonial structures, and plasmodial slime molds, which exist as a large, multinucleated mass of cytoplasm known as a plasmodium.
122
What is the collective term for the entire arrangement of metulae and sterigmata on a single branch of a Penicillium conidiophore?
Answer:
pencillus
In Penicillium, the conidiophore branches into metulae, which then bear phialides (sterigmata) that produce conidia. The entire brush-like structure formed by these branches, metulae, and sterigmata is collectively referred to as the 'penicillus', which is derived from the Latin word for a painter's brush.
123
What is the common name often used to describe the group of organisms classified under Oomycota?
Answer:
egg fungi
Oomycetes are frequently referred to as 'egg fungi' or 'water molds' due to their filamentous growth and the production of large, non-motile female gametes called oospheres. Although they were historically classified as fungi, they are now phylogenetically distinct, belonging to the Stramenopiles group.
124
Which structure is located beneath the extracellular substances in bacteria?
Answer:
cell wall
Extracellular substances like the capsule or slime layer form the outermost boundary of the bacterium. Beneath these layers lies the cell wall, which provides structural support and shape to the cell. The cell wall is a critical component of the cell envelope, protecting the underlying plasma membrane.
125
What is the characteristic shape of bacteria classified as bacilli?
Answer:
rod
The term 'bacillus' (plural: bacilli) is derived from the Latin word for a small rod. In bacteriology, this term is exclusively used to describe bacteria that exhibit an elongated, cylindrical, or rod-like morphology, distinguishing them from spherical cocci or helical spirilla.
126
Which structural component provides chemical and enzymatic resistance to bacterial endospores?
Answer:
Proteinaceous coat
The endospore coat is primarily composed of highly cross-linked proteins. This proteinaceous layer acts as a robust physical and chemical barrier, protecting the dormant bacterial cell from environmental stressors, including enzymes, detergents, and various chemical agents.
127
Which taxonomic division includes the genus Mucor?
Answer:
zygomycota
The genus Mucor is classified within the division Zygomycota. This division is characterized by the formation of a thick-walled resting spore known as a zygospore, which results from the fusion of two gametangia. While modern taxonomy has reclassified many of these fungi, Zygomycota remains a traditional grouping used to describe these specific types of molds.
128
Into how many major groups are slime molds generally classified?
Answer:
two
Slime molds are traditionally divided into two major groups: the plasmodial slime molds (Myxomycota) and the cellular slime molds (Acrasiomycota). Plasmodial slime molds form a single, large, multinucleate mass, whereas cellular slime molds exist as individual amoeboid cells that aggregate to form a pseudoplasmodium during their reproductive phase.
129
Do viruses in the order Sagovirales possess an envelope?
Answer:
envelope
Viruses classified within the Sagovirales order are characterized by the presence of a lipid envelope. This envelope is crucial for the virus's ability to attach to and enter host cells, as it contains specific glycoproteins that interact with host cell receptors.
130
Approximately how many species are estimated to exist within the phylum Ascomycota?
Answer:
60000
Ascomycota is the largest phylum of fungi, commonly known as sac fungi. Scientific estimates suggest there are over 60,000 described species, though the actual number of existing species is likely much higher due to many undiscovered or cryptic species in various ecosystems.