Question 1

The first vascular plants were:

Accepted Answer

Vascular plants are those which have well developed vascular tissues, xylem and phloem.A) Algae are simple, thalloid and without vessels.B) Bryophytes have a body more differentiated than algae and have root-like and leaf-like structures but lack proper vessels.C) Pteridophytes are evolutionarily the first plants to develop true vascular tissues, xylem and phloem.D) Angiosperms have true vessels but are not the first plants to possess them.So, the answer is 'Pteridophytes'.

Question 2

The female sex organs in Riccia and Funaria is:

Accepted Answer

In Bryophytes, archegonium is the female sex organ. The female shoot arises from the base of the male shoot and called an archegonial branch or archegoniophore. The apex of female shoot is called the female receptacle from which a cluster of archegonia arise intermixed with non-capitate paraphysis. Each archegonium has a stalk, flask-shaped center, and a neck. Venter encloses a basal egg cell (oosphere) and an upper smaller venter canal cell. The neck consists of 6 or more neck canal cells (6-11).

Question 3

The antherozoids of Marchantia are:

Accepted Answer

An antheridium (plural: antherida) is a haploid structure or organ producing and containing male gametes (called antherozoids or sperm). In general, the male gametes (antherozoids) are produced in globose structures (antheridia), that are either stalked or sunken in the gametophyte. The antherozoids of Marchantia are long, curved, and biflagellate.

Question 4

The gametophytic generation in pteridophytes is commonly called ___________.

Accepted Answer

In ferns, gametophytic generation  is represented by heart-shaped prothallus.

Question 5

Spirogyra has a:

Accepted Answer

Correct Option: AExplanation:The life cycle in Spirogyra is haplontic, as dominant phase in life cycle is haploid (n) and diploid phase is represented by only zygospore and it undergoes meiosis.Therefore, in the haplontic life cycle of Spirogyra no true alternation of distinct plants was observed. Rather, alternation of chromosome numbers from haploid to diploid and back to haploid conditions can be noticed.

Question 6

Most plants exhibit alternation of generation during their life cycle. Which reproductive cells form the sporophytic and gametophytic plant body respectively?

Accepted Answer

Most plants exhibit alternation of generations in their life cycle. These plants have a diploid sporophytic phase that produces the haploid spores which form the gametophyte. This haploid gametophyte produces haploid gametes which then fuse to form the diploid sporophyte and that further develops into a plant. Thus, the correct answer is option B.

Question 7

Give the differences between monocots and dicots.

Accepted Answer

The differences between monocots and dicots are: (i) Monocots-    (a) Seeds with one cotyledon.    (b) Leaves have parallel venation.     (c) Root system-fibrous.(ii) Dicots-     (a) Seeds with two cotyledons.      (b) Leaves show reticulate venation.      (c) Root system- taproot.

Question 8

Which kind of life-cycle pattern is exhibited by seed-bearing plants?

Accepted Answer

In a diplontic life cycle, the dominant free-living phase is the diploid (2n). The sporophyte is photosynthetic. The gametophytic phase is represented by single to few-celled haploid gametophyte. All seed-bearing plants, i.e., gymnosperms and angiosperms exhibit this type of life cycle.So the correct option is B.

Question 9

Assertion : The megaspore mother cell divides mitotically to produce four spores.Reason : Megaspore mother cells are diploid and megaspore is haploid.

Accepted Answer

The megaspore mother cell is diploid. This divides by meiotic division and produce four haploid megaspores.

Question 10

Asexual reproduction in liverworts takes place by ____________________.

Accepted Answer

Asexual reproduction in liverworts takes place by fragmentation of thalli, or by the formation of specialised structures called gemmae.So the correct option is A.

Plant Kingdom