FREE NEET Biology Practice MCQ Test: Plant Kingdom Exercise 4 Questions Answers With Detailed Explanations [PDF]

Answer: (c)

Answer: (a)

Answer: (d)

Answer: (b)

Stele is a column containing vascular tissues which is surrounded by pericycle and separated from ground tissue by endodermis. Siphonostele is medullated protostele or protostele with a central non-vascular pith. Leaf gaps are absent. Siphonostele is of two types : In Ectophloic siphonostele, central pith is surrounded successively by xylem, phloem, pericycle and endodermis. In amphiphloic siphonostele there is a central pith and xylem is surrounded on either side by phloem, pericycle and endodermis. It is found in Osmunda and Equisetum.

Answer: (b)

In Chlamydomonas sexual reproduction takes place through isogamy, anisogamy, and oogamy. Isogamy i.e.,the fusion of similar gametes is the common mode of sexual reproduction in it. Anisogamy is fusion of morphologically similar but physiologically different cells. Oogamy is fusion of different gametes.

Answer: (d)

Answer: (c)

Answer: (c)

Answer: (a)

Because endosperm is haploid (n) and formed before fertilization and megaspore mother cell divides reductionally to form a linear tetrad of haploid reductionally to form a linear tetrad of haploid megaspores and microspore (= pollen grain) is the first stage of the gametophyte (n).

Answer: (b)

Answer: (d)

The leaves in gymnosperms are well adapted to withstand extremes of temperature, humidity and wind. In conifers, the needle like leaves reduces surface area. Their thick cuticle and sunken stomata also help to reduce water loss.

Answer: (a)

Answer: (c)

Answer: (c)

Conifers (Gymnosperms) differ from grasses (angiosperms) because in gymnosperms the female gametophyte is actually endosperm which is made before fertilization. While in grasses endosperm is a tissue formed by the fertilization of second male gamete to polar nuclei. Moreover in gymnosperms the endosperm is a haploid tissue while in angiosperms it is triploid.

Answer: (c)

Answer: (b)

Answer: (d)

An elater is a cell (or structure attached to a cell) that is hygroscopic, and therefore will change shape in response to changes in moisture in the environment. Elaters come in a variety of forms, but are always associated with plant spores. In plants that do not have seeds, they function in dispersing the spores to a new location. In the liverworts, elaters are cells that develop in the sporophyte alongside the spores. They are complete cells, usually with helcial thickenings at maturity that respond to moisture content. In most liverworts, the elaters are unattached, but in some leafy species (such as Frullania) a few elaters will remain attached to the inside of the sporangium (spore capsule). The elaters by hygroscopic movement help in spore dispersal.

Answer: (b)

Coconut tree is distributed in coastal areas since it is adapted to saline water.

Answer: (a)

Answer: (a)