Biology MCQs
Topic Notes: Biology
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
31
Which of the following is classified as a false fruit (pseudocarp)?
Answer:
apple
A false fruit, or accessory fruit, is one that develops from parts of the flower other than the ovary, such as the receptacle. In apples, the fleshy part we consume is derived from the receptacle, while the true ovary forms the core.
32
Which of the following plants produces fruits that develop and mature underground?
Answer:
groundnut
The groundnut (Arachis hypogaea), also known as the peanut, is unique because after fertilization, the flower stalk (gynophore) elongates and pushes the developing ovary into the soil. The fruit then matures underground. In contrast, potatoes and onions are modified stems/leaves, and carrots are taproots, none of which are botanically classified as fruits.
33
Which specific fruit type develops from a bicarpellary, syncarpous, and inferior ovary, characterized by a persistent calyx that forms a pappus?
Answer:
Cypsela
A cypsela is a dry, indehiscent fruit derived from an inferior ovary. It is common in the Asteraceae family, where the calyx is modified into a pappus, a structure that aids in wind dispersal of the seeds.
34
What is the name of the stalk that attaches the seed to the inner wall of the legume pod?
Answer:
Funiculus
The funiculus (or funicle) is the stalk-like structure that connects the ovule (and later the seed) to the placenta within the ovary wall. In a gram pod, the funiculus serves as the vascular connection, providing nutrients to the developing seed until it reaches maturity.
35
What is the protective outer layer of an angiosperm seed that prevents the embryo from desiccation?
Answer:
seed coat
The seed coat, or testa, is the tough, protective outer covering of a seed. It is derived from the integuments of the ovule and serves to protect the delicate embryo inside from mechanical injury, pathogens, and excessive water loss (desiccation).
36
Following the process of fertilization and seed development, which structure is derived from the integuments that originally surrounded the ovule?
Answer:
seed coat
During the development of a seed, the integuments of the ovule undergo maturation and hardening to form the seed coat, also known as the testa. This protective outer layer serves to shield the developing embryo from mechanical injury, desiccation, and pathogen invasion until conditions are favorable for germination.
37
Which of the following plants is recognized for producing winged seeds to aid in dispersal?
Answer:
Tacoma
Tecoma (often spelled Tacoma) species produce seeds with wing-like structures. These adaptations allow the seeds to be carried by wind currents, facilitating dispersal away from the parent plant to colonize new areas.
38
What is the specific term for the scar on the seed coat that marks the point of attachment to the ovary wall?
Answer:
hilum
The hilum is a prominent scar found on the seed coat of a seed. It represents the point where the ovule was attached to the funiculus, which in turn connected the ovule to the ovary wall during development. This structure is essential for identifying the orientation of the seed.
39
From which specific structure does the seed coat originate during plant development?
Answer:
integument
The seed coat, or testa, is derived from the integuments of the ovule. Following fertilization, the integuments undergo structural changes, hardening and dehydrating to form a protective outer layer that shields the developing embryo from mechanical injury, desiccation, and pathogen invasion until germination occurs.
40
What are the physical characteristics of the coconut seed coat?
Answer:
hard
The coconut seed coat, or endocarp, is exceptionally thick and hard. This structural adaptation provides significant protection to the embryo inside, allowing the seed to survive long-distance dispersal via ocean currents before germination.