Which one of the following parts of an ovule possesses reserve food?
- A.Integument
- B.Funicle
- C.Chalaza
- D.Nucellus
Correct answer
Explanation
The correct answer is D, Nucellus. The nucellus is the mass of tissue inside the ovule whose cells carry stored food, and the embryo sac develops within it. An ovule is attached to the placenta of the ovary by a stalk. It is wrapped in one or two protective layers that leave a small opening, the micropyle, at one end. Inside these layers lies the nucellus, made of cells rich in reserve food, and embedded in it is the embryo sac, or female gametophyte, which holds the egg cell. NCERT's Class 12 chapter on sexual reproduction in flowering plants describes the nucellus in exactly these terms. Option A is wrong because the integuments are the protective coats around the ovule; they later form the seed coat. Option B is wrong because the funicle is only the stalk that attaches the ovule to the placenta. Option C is wrong because the chalaza is the basal end of the ovule, opposite the micropyle, where the integuments and nucellus meet. Exam tip: funicle = stalk, integument = coat, nucellus = food store, embryo sac = female gametophyte.
Practice Questions
View allWhich one of the following is not used as fertilizer?
- A.Ammonium nitrate
- B.Ammonium sulphide
- C.Ammonium phosphate
- D.Ammonium sulphate
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Ammonium sulphide is an unstable, foul-smelling compound that breaks down to release ammonia and toxic hydrogen sulphide, so it is not used as a fertiliser.
Read the full explanation →The focal length of the objective lens of a telescope is 50 cm. If the magnification of the telescope is 25, then the focal length of the eye-piece is
- A.12.5 cm
- B.5 cm
- C.2 cm
- D.10 cm
Show answer
For an astronomical telescope in normal adjustment the magnifying power equals the focal length of the objective divided by that of the eyepiece, so the eyepiece focal length is 50 ÷ 25 = 2 cm.
Read the full explanation →The major source of vitamins and minerals for vegetarians is
- A.black gram and wheat.
- B.rice and mustard.
- C.vegetables and fruits.
- D.soya bean and milk.
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Vegetables and fruits supply most of the vitamins and minerals in a vegetarian diet, which is why they are called protective foods.
Read the full explanation →Which one of the following compounds is used in black and white photography?
- A.AgF
- B.AgBr
- C.AgCl
- D.Ag2SO4
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Silver bromide is the light-sensitive compound coated on black and white photographic film and paper, because light breaks it down into tiny grains of silver metal.
Read the full explanation →Which one of the following statements about speed and velocity is correct?
- A.Speed and velocity both are vector quantities.
- B.Speed and velocity both are scalar quantities.
- C.Speed is vector quantity and velocity is scalar quantity.
- D.Speed is scalar quantity and velocity is vector quantity.
Show answer
Speed tells only how fast a body moves, while velocity also tells the direction of motion, and a quantity with both magnitude and direction is a vector.
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