31. Which of the following relationship was not studied by Mendel?
[A] Flower colour and seed colour
[B] Height and seed colour
[C] Flower colour and shape of pollen grain
[D] Height and seed coat colour
Show Answer
Correct Answer: C [Flower colour and shape of pollen grain]
Notes:
Flower colour and shape of pollen grain relationship was not studied by Mendel.
32. Which metal microparticles are used in gene guns?
[A] Aurum
[B] Nitrogen
[C] Magnesium
[D] Cuprum
Show Answer
Correct Answer: A [Aurum]
Notes:
The gene gun technique uses gold-coated microparticles along with the DNA. Aurum is a Latin word for gold. The other metal used for this technique is tungsten.
33. The best milch breed in the word is ____:
[A] Chittagong
[B] Holstein-Friesian
[C] Deoni
[D] Sindhi
Show Answer
Correct Answer: B [Holstein-Friesian]
Notes:
Holstein Friesian cows are world’s highest-production dairy animals and dominate the global dairy industry. These cows originated in Dutch provinces of North Holland and Friesland, and Schleswig-Holstein in Northern Germany. They are known as Holsteins in North America and Friesians in UK and Ireland.
34. What is thick vein present in the middle of the leaf called?
[A] Leaf venation
[B] Parallel venation
[C] Midrib
[D] Reticulate
Show Answer
Correct Answer: C [Midrib]
Notes:
A thick vein seen in the middle of the leaf is called the midrib. Pinnately veined leaves have one large central vein, called the midrib, which extends from the base of the blade to its tip. Other large veins branch off on each side of the midrib. The leaves of beech, birch, and elm trees have such a vein pattern.
35. The edible part of an onion is ____:
[A] Fleshy leaves
[B] Aerial stem
[C] Modified root
[D] Aerial flower
Show Answer
Correct Answer: A [Fleshy leaves]
Notes:
The edible portion in an onion is swollen leaves with a bit of stem. They are bulbs which, like garlic and leeks, are modified stems in which the primary storage tissue is expanded leaf bases. They come in white, yellow, and red varieties. The swollen leaves have sugar as stored food in them.
36. The hydrophilic nature of DNA is due to the presence of ____:
[A] A number of hydrogen bonds
[B] Phosphate group
[C] Thymine base
[D] Deoxyribose sugar
Show Answer
Correct Answer: A [A number of hydrogen bonds]
Notes:
The phosphate groups on DNA are ionic and charged. Each phosphate group on the DNA backbone has one unit of negative charge (-1). Charged molecules attract water and are hydrophilic. DNA has two hydrophilic polar external backbones made of sugars and phosphate groups joined by ester bonds. Therefore, DNA as nucleic acid is characterized by presence of phosphodiester bond.
37. The cells which are colsely associated and interacting with guard cells are ____:
[A] Transfusion tissue
[B] Complementary cells
[C] Subsidiary cells
[D] Hypodermal cells
Show Answer
Correct Answer: C [Subsidiary cells]
Notes:
Guard cells interact physiologically and mechanically with subsidiary cells. Guard cells are those which have chloroplasts and control the opening of stomata. But, subsidiary cells are those which support the guard cells and they do not have chloroplasts.
38. The plant that behaves as a root parasite is _____:
[A] Euphorbia
[B] Santalum
[C] Cuscuta
[D] Ficus
Show Answer
Correct Answer: C [Cuscuta]
Notes:
Plants which either obtain readymade organic food prepared by other plants or absorb water and minerals from other plants to prepare their own organic food are called parasitic plants. Cuscuta (Doddar) is a total stem parasite.
39. “Slipper animalcule” is the common name for ___:
[A] Paramecium
[B] Trypanosoma
[C] Monocystis
[D] Plasmodium
Show Answer
Correct Answer: A [Paramecium]
Notes:
“Animalcule” is a old term for a microorganism first used by Anton Van Leeuwenhoek means “small animal”. A paramecium is shaped somewhat like a slipper (a soft shoe), so it is called the slipper animalcule. Other better-known animalcules include: Amoeba, called Proteus animalcule etc.
40. Leaves of many grasses are capable of folding and unfolding because _____:
[A] They have stomata on both sides of the leaf
[B] Their mesophyll is not differentiated into palisade and spongy parenchyma
[C] They have high levels of silica
[D] They have specialised bulliform cells
Show Answer
Correct Answer: D [They have specialised bulliform cells]
Notes:
Bulliform cells are large, bubble-shaped epidermal cells that occur in groups on the upper surface of the leaves of many grasses. These cells, by their turgor changes, cause rolling and unrolling of the leaves thus regulating water loss.
