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
51
Which hormone inhibits the germination of seeds?
Answer:
Abscisic acid
Abscisic acid (ABA) maintains seed dormancy. Germination occurs when ABA levels drop or are overridden by hormones like gibberellins, often triggered by environmental cues like rain or cold.
52
The movement of water through the cell wall and intercellular spaces is the:
Answer:
Apoplastic pathway
The apoplastic pathway is the movement of water and solutes outside the plasma membranes of living cells. It is the primary route for water movement in the root cortex until it reaches the endodermis.
53
Which cell type is responsible for the 'gritty' texture of a pear?
Answer:
Sclereids
Sclereids are a type of sclerenchyma cell. Their thick, lignified walls provide the hardness felt in nut shells, seed coats, and the stone cells in pears.
54
What is 'vernalization'?
Answer:
The use of cold treatment to induce flowering
Some plants require a period of cold temperatures (winter) before they are capable of flowering. This ensures that the plant does not bloom prematurely during a warm spell in autumn.
55
Which type of root system is characteristic of most monocots?
Answer:
Fibrous root system
Monocots usually have a fibrous root system where the embryonic root dies and is replaced by many small roots growing from the stem, creating a dense mat that prevents soil erosion.
56
What is the 'bark' made of?
Answer:
Everything outside the vascular cambium
Bark includes all tissues external to the vascular cambium, primarily the secondary phloem and the periderm (the outer protective layers).
57
Which of the following describes 'positive phototropism'?
Answer:
Growth toward light
Positive phototropism is the growth of plant shoots toward a light source. This is mediated by the redistribution of auxin to the shaded side of the stem, causing those cells to elongate faster.
58
The 'petiole' is the structure that connects:
Answer:
The leaf blade to the stem
The petiole is the stalk of a leaf. It supports the blade and contains the vascular tissues that connect the leaf to the rest of the plant's transport system.
59
Which of the following is NOT a component of the vascular system in plants?
Answer:
Mesophyll cells
Mesophyll cells are part of the ground tissue system and are primarily involved in photosynthesis. Xylem and phloem cells make up the vascular tissue system.
60
Which specialized stem is a horizontal shoot that grows along the surface, like in strawberries?
Answer:
Stolon (runner)
Stolons, or runners, allow plants to reproduce asexually. New 'plantlets' form at nodes along the runner, enabling the plant to spread across the ground.