Question

The process of double fertilization in the gymnosperms results in Select one: , the 2n zygote b. the megagametophyte tissue c. the seed coat d. double fertilization is not found in the gymnosperms The vascular plants have two synapomorphies that define them. One is vascular tissue and the other is: Select one: a. chlorophyll b c. diploid-dominant life cycle d. oögamy Plant cell mitosis differs from animal cell mitosis in the formation of a structure that aids in the development of the cell wall. This structure is the: Select one: a. microfiliments c. phycoplast d. spindle

Answer 1

Ans. 1. D. double fertilization is not found in gymnosperms.

True double fertilization is a characteristic of angiosperms (sperms) where diploid zygote and 3n endosperm are produced after double fertilization.

Note: A. the 2n zygote. Very few members of gymnosperm exhibit the event of double fertilization to form diploid zygotes. However, endosperm in not produced.

Ans. 2. C. diploid dormant life cycle.

Chlorophyll b is present in all plants. (non-vascular and vascular plants)

Endosperm is present only in angiosperms.

Oogamy i.e. fertilization of female gametes with a morphologically different male gamete is also present in all plants.     

Ans. 3. B phragmoplast.

Phragmoplast laid during anaphase later forms cell wall during cytokinesis. Phragmoplast is unique to plant cell division and absent in animal cell cycle.

Ans. 4. D. all of the above.

These leaf-like structures are part of the gametophyte generation, being few cell-layers thick and lack stomata/ vascular bundles.

Note: stomata are generally present in leaves. However, they are absent in leaf-like structure (gametophytes) of mosses and liverworts while may be present on sporophyte generation. Thus, stomata is NOT an unifying trait of leaves of all plants through the Plant Kingdom. However, presence of cuticle, stomata and vascular bundles may be considered a set of unifying trait of leaves.

Ans. 5. C. ovary.

All fruit develop from ovary and/or other floral parts after fertilization. A fruit consisting of floral parts like petals/ sepals along with ovary at maturity is called accessory fruit.

A fruit can’t develop without ovary.

Note: Though the edible part of an apple develops from thalamus, the formation of fruit can’t develop without (fertilization in) the ovary. So, ovary is more appropriate option.

And. 6. B. Cnidocytes.

It is a characteristic of Cnidarians.

Ans. 7. C. endothermy

These animals are heterothermic and do not exhibit true endothermy. These have hair, and nipple for nourishing younglings by lactation like mammals.

Ans. 8. D. Annelida

Ans. 9. C. neither diploblastic nor triploblastic

Sponges lack tissue level organization.