General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
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
What is 'translocation' in plants?
Answer:
The movement of sugars in the phloem
Translocation is the transport of photosynthetic products from sources (where they are made) to sinks (where they are used or stored).
32
Which of the following is a role of 'Gibberellins' in seeds?
Answer:
Promote the breakdown of starch into sugars for the embryo
After water is absorbed (imbibition), the release of gibberellins signals the seed to break dormancy and stimulates enzymes like alpha-amylase to digest stored food.
33
In a root, the vascular tissue is surrounded by a layer called the:
Answer:
Endodermis
The endodermis is a single layer of cells that acts as a selective barrier between the cortex and the vascular cylinder (stele).
34
Which plant tissue includes the 'mesophyll'?
Answer:
Ground tissue
Ground tissue is the 'filler' tissue of the plant that is neither dermal nor vascular. In the leaf, this ground tissue is called mesophyll and is specialized for photosynthesis.
35
The loss of water from the leaves of a plant is called:
Answer:
Transpiration
Transpiration occurs primarily through the stomata. While it leads to water loss, it is also the driving force that pulls water and minerals from the roots to the leaves.
36
Which hormone is associated with 'cell division' and is found in coconut milk?
Answer:
Cytokinin
Cytokinins were first discovered in research on cell division. Coconut milk is rich in cytokinins, which is why it was historically used to stimulate growth in plant tissue cultures.
37
What is the 'radicle'?
Answer:
The embryonic root
The radicle is the part of the plant embryo that develops into the primary root upon germination.
38
Which cell type in the vascular tissue is involved in lateral transport of water and nutrients?
Answer:
Ray parenchyma
Vascular rays, consisting of parenchyma cells, run radially through the secondary xylem and phloem, facilitating the transport of materials across the stem.
39
What are 'mycorrhizae'?
Answer:
Mutualistic associations between roots and fungi
Mycorrhizae greatly increase the effective surface area of roots for absorbing minerals (especially phosphorus) from the soil, while the plant provides the fungi with sugars.
40
Which of the following describes 'positive gravitropism'?
Answer:
Roots growing downward
Positive gravitropism is growth in the direction of gravity. Roots show this response to ensure they penetrate the soil to find water and nutrients.