Sexual reproduction in angiosperms: Introduction

Sexual reproduction in plants ensure sufficient variations for the purpose of evolutionary successful journey of a species in its environment .
An angiosperm is a plant which bears seed in ovary /  ovaries of a  flower . 
Flower is a reproductive structure which is absent in other types of plants . 
Gymnosperms bear naked seeds not enclosed in ovaries .
Seeds are matured form of ovule which are borne in ovaries which itself is basal part of female part pistil . A pistil may be having single carpel or more than one carpel . If a pistil is having four carpel it may give its indication by showing four carpels in fused or unfused conditions . 
The top most part of pistil is stigma which is generally hairy and sticky to trap pollen grains being brought down by wind or water currents or animals like honey bees , birds or bats . 
Stigma is followed by a stalk like style which meets into lower swollen portion called ovary . 
Eggs for making zygote are produced in ovaries only . 
Pollen grain which land on stigma may or may not germinate on stigma depending on chemical  compatibility between two species .
Germination if allowed results into formation of pollen tube which serve to carry gametes for fusion with polar nuclei and egg nucleus present in ovarian region . 
After fertilisation zygote is formed and further divide to form next stage of embryo . 
Side by side another structure called endosperm also develop although much faster than embryo . Embryo remain protected in hard seed coat and nourished by endosperm . In dormant seeds development of embryo is suspended .

Sexual reproduction in plants 

Pollen being transported by insect in Entomophily 

  QUESTIONS TO BE ATTEMPTED

CH – 1 REPRODUCTION  IN  ORGANISMS

1. What is the  life span of      crow-----------------------

Ans- 15  years

2.  asexual reproduction  involves  gametes-------------------(yes/ no)

Ans-yes

3.The genetically  identical  offsprings   are called  --------------------------

Ans-clones

4. Asexually  reproducing   structure of sponges  called---------------------------

Ans-gemmule

5. Asexually  reproducing  forms  of penecillium  are called-----------------------

6.Name  any   one  Vegetative  propagules   of   vegetativepropagation under  asexual

reproduction Ans-conidia

------------------------

ans-runner,rhizome

7.-------------------------Plant  is  called  terror of  Bengal

Ans-water hyacinth

8. Adventitious  buds  arise  from the    notches present  at  margins of    leaves

 Of   ------------------------------plant

Ans-bryophyllum

9.The  period of growth  before  sexual  maturity in animals  is  ---------------------------------

Ans-juvenile phase

10. The period of growth before sexual maturity in plant  is  ---------------------------------

Ans-vegetative  phase

11. Under the unusual flowering phenomenon, --------------------- species    flower only once

In their life time, generally after 50-100 years.

Ans-bamboo

12. Name the botanical  name  of    Neelakuranji------------------------Which  flowers  once in 

       12 years

Ans-strobilanthus kunthiana

13.------------and----------animals   shows  Oestrous  cycle  of  reproductive  phase

Ans-dogs ,deer

14.----------is  the  technical  name the of the mammals    which reproduce during  favorable  seasons

Ans-continous breeders

15.-----------and  ------------- are the  example  of   continuous breeder  of  mammals.

Ans monkey,apes

16.---------------- is   the  other  name  of  Isogametes  which   are similar in  appearance.

homogametes

17.Cucurbit  and  coconut   are   ------------  plants(monoecious/dioecious)

18.Diploid  organisms  has    specialized cells  to  produce  gametes     called--------------------

Ans-meiocytes

 

19.The  female  gametes    undergoes  development to  form new   organism  without  fertilization  called-------------------------------------

Ans-parthenogenesis

20.During  embryogenesis     the  zygote  undergoes------------------and--------------------

Ans-cell  division  and  differentiation

21.The  ovary  develops  to-----------------which  develops  a thick wall  called----------------

Ans-fruit,pericarp

 

CH 2  -SEXUAL     REPRODUCTION  IN  FLOWERING  PLANTS

1.The   microsporangia  develop  further  and    become

     a. Pollensacs b.pollengrain c.   tetrad    d. male  gamete

ans-pollen sac

2.When the    anther  is   young  a group  of  compactly  arranged   homogenous  cells  called

a.Tetrad b.female  gametec.pistild.staminode

ans-tetrad

3.One  microspore  mother cell  can  give  -----------------------male gametes

       a.         8                   b.             16                   c            20                  d.4

ans-8

4.One megaspore  mother cell  can  produce             ---------------- female   gamete

     a.1                     b.2                     c.4                          d.6

ans-1

5.The  region  on the  pollen  grain   where  the  sporopollenin   absent is  called

a.Pectin                        b   cellulose                    c    germpore               d. intine

ans-germpore

6.The  composition  of   intine     is ----------------------------------

a.cellulose pectin,     b.cellulosehemicelluosc.lignin ,pectin

ans-cellulose  pectin

7.A  pollen  grain  contain--------------------------------------

a.vegetative cell  and  generative  cell                   b.mitosis  meiosis

ans-vegetative cell  and  generative cell

8.The   ovule  has   small  structure  attached to  placenta    by  means   of  stalk  called-------------

a.Funicleb.integument                       c. chalaza            d. micropyle

ans-funicle

9.Enclosed within  the  integument  is  a mass  of cells called------------------

   A chalaza           b   integument                   c        nucellus                   d micropyle

Ans-nucellus

10.the     egg  apparatus  of  the  angiosperm  contain  --------------------------

A  3  cells                 b.4cells               c.5 cells            d.9 cells

Ans-3 cells

11.cleistogamous flower      has  ------------------pollination

a.self pollination       b. cross  pollination   c.pollination     d. inter pollination

ans-cross pollination

12.Polllen  grains  of  ------------------- flowers   is       ribbon like submerge in  water  

a.sea     grass             b.carrot  grass      c. lemon  grass          d.zosteria

ans-sea grass

13.Continued self pollination  leads  to-----------------------

a.Self      pollination          b. inbreeding depression        c  cross  pollination

ans-inbreeding depression

14.Emasculation  and  bagging  are   techniques  of--------------------------------

a.plant  breeding       b. cross  pollination       c    tissue culture  d.meristem culture

ans-plant breeding

15.Embryo of  monocot  plant  possess  single  large  cotyledon    called-------------------------

Ans-scutellum

a.meristem           b      scutellum c  platellum d.syngamy

16.The   residual      endosperm that  found  in black    pepper    and beet------------------

Ans-perisperm

a.perisperm b.endosperm   c.nucellus               d  .nucleus

17.apple  is  a  -------------------------fruit

a.true      fruit           b  .false  fruit                c.soft fruit              d .red fruit

ans-false fruit

18.Fruits  that  develops  without  fertilization  is called------------------------------

       A .parthenocarpic  fruit                b. false  fruit            c.yellow  fruit    d.meristem fruit

Ans-parthenocarpic fruit

19.Seeds   that  develop without  fertilization   is called-----------------------------------

a.Apomictic  seeds   b      white  seeds     c. multiple  seed  d   grain  seed

ans-apomictic seed

20. Occurance of   more than one  embryo in the  seed  is  referred as---------------------

a.polyembryony b.  apomixes c.perisperm          d.  scutellum

ans-polyembyony