Structural Organisation in Animals and Plants
- In old trees the greater part of seco[...] dark brown and resistant to insect attack due [...](a) secretion of secondary metabolites and their deposition in the lumen of vessels.(b) deposition of organic compounds like tannins and resins in the centr… Answer: 2. (a) and (b) Only Heartwood is dark brown and resistant to insects and microbes because of chemical deposits in the central, old x... 1
- The flowers are Zygomorphic in :(a) Mustard(b) Gulmohar(c) Cassia(d) Datura(e) ChillyChoose the correct answer from the options given below : Answer: 3. (b), (c) Only Zygomorphic flowers can be divided into two equal halves in only one vertical plane. Gulmohar and Cassia (family Fa... 1
- Which of the following is not observed during apoplastic pathway ? Answer: 4. The movement is aided by cytoplasmic streaming In the apoplastic pathway water moves only through cell walls and intercellular sp... 1
- Read the following statements about the vascular bundles :(a) In roots, xylem and phloem in a vascular bundle are arranged in an alternate manner along the different radii.(b) Conjoint closed vascular bundles do not possess cambium(c) In open vascula… Answer: 3. (b), (c), (d) and (e) Only Check each statement against NCERT; the key says statement (a) does not hold, so the answer is (b), (c... 1
- Match Column - I with Column - II.Column - I (floral formulae) | Column - II(a) %♀♂ K(5) C1+2+(2) A(9)+1 G̱(1) | (i) Brassicaceae(b) ⊕♀♂ K(5) C(5) A5 G̱(2) | (ii) Liliaceae(c) ⊕♀♂ P(3+3) A3+3 G̱(3) | (iii) Fabaceae(d) ⊕♀♂ K2+2 C4 A2−4 G̱(2) | (iv) So… Answer: 1. (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i) Identify the family from each floral formula. (a) Zygomorphic, K(5), C 1+2+(2), A (9)+1, s... 1
- Select the correct pair. Answer: 3. Cells of medullary rays that form part of cambial ring - Interfascicular cambium Check each pair. Large colourless empty cells in... 1
- Diadelphous stamens are found in : Answer: 3. Pea In diadelphous stamens, filaments are fused into two bundles. Pea (Fabaceae) has 9 fused plus 1 free stamen, (9)+1 . China ro... 1
- Match List - I with List - II.List - I | List - II(a) Lenticels | (i) Phellogen(b) Cork cambium | (ii) Suberin deposition(c) Secondary cortex | (iii) Exchange of gases(d) Cork | (iv) PhellodermChoose the correct answer from the options given below. Answer: 2. (a)-(iii), (b)-(i), (c)-(iv), (d)-(ii) Match the structures with their roles: Lenticels allow exchange of gases: (a)-(iii). Cork... 1
- Match List - I with List - II.List - I | List - II(a) Cells with active cell division capacity | (i) Vascular tissues(b) Tissue having all cells similar in structure and function | (ii) Meristematic tissue(c) Tissue having different types of cells |… Answer: 1. (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii) Match by definition: Actively dividing cells: meristematic tissue, (a)-(ii). All cells ali... 1
- The ovary is half inferior in : Answer: 4. Plum The position of the ovary relative to other floral parts decides this. In plum (and rose, peach) the flower is perigynous an... 1
- Ray florets have : Answer: 1. Inferior ovary Key idea: In sunflower (family Asteraceae), ray florets are female or sterile and have an inferior ovary. Asterace... 1
- Identify the incorrect statement. Answer: 3. Sapwood is the innermost secondary xylem and is lighter in colour. Key idea: Heartwood is the innermost secondary xylem and is da... 1
- The transverse section of a plant shows following anatomical features :(a) Large number of scattered vascular bundles surrounded by bundle sheath.(b) Large conspicuous parenchymatous ground tissue.(c) Vascular bundles conjoint and closed.(d) Phloem p… Answer: 1. Monocotyledonous stem Key idea: Scattered, conjoint, closed vascular bundles with bundle sheaths and no phloem parenchyma indicat... 1
- The roots that originate from the base of the stem are : Answer: 1. Fibrous roots Key idea: Roots arising from the base of the stem are adventitious and, in monocots, form a fibrous root system. In... 1
- Phloem in gymnosperms lacks : Answer: 4. Both sieve tubes and companion cells Key idea: Gymnosperm phloem has sieve cells and albuminous cells. Sieve tubes and companion... 1
- Placentation, in which ovules develop on the inner wall of the ovary or in peripheral part, is : Answer: 3. Parietal Key idea: Placentation is the arrangement of ovules on the placenta inside the ovary. Marginal: along one margin of a si... 1
- Xylem translocates : Answer: 4. Water, mineral salts, some organic nitrogen and hormones Xylem sap carries mostly water and minerals, but also some organic nitro... 1
- Which of the statements given below is not true about formation of Annual Rings in trees ? Answer: 4. Annual rings are not prominent in trees of temperate region. Key idea: Annual rings are clearest where seasons differ sharply, so... 1
- Grass leaves curl inwards during very dry weather. Select the most appropriate reason from the following : Answer: 2. Flaccidity of bulliform cells Grass leaves have large thin-walled bulliform (motor) cells in the upper epidermis. In dry weather... 1
- Stomata in grass leaf are Answer: 1. Dumb-bell shaped Grass (monocot) leaves have dumb-bell shaped guard cells. Kidney-shaped guard cells are in dicots. Rectangular a... 1
- Sweet potato is a modified Answer: 3. Adventitious root Sweet potato is a root that stores food, and it arises from a non-root part, so it is an adventitious root. Tap... 1
- Plants having little or no secondary growth are Answer: 1. Grasses Secondary growth depends on a vascular cambium, which is weak or absent in monocots. Grasses are monocots with closed vas... 1
- Casparian strips occur in Answer: 4. Endodermis Casparian strips are waterproof bands of suberin on the radial and tangential walls of endodermal cells. They force wa... 1
- Secondary xylem and phloem in dicot stem are produced by Answer: 3. Vascular cambium Secondary growth in a dicot stem is by the lateral meristem called vascular cambium. Vascular cambium cuts secon... 1