Plant Kingdom 4 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

what are the 2 main whorls in a plant?

A

(i) Reproductive whorl
- Androecium
unit: stamen
stamen consists of filment( sterile) and enther ( fertile.

  • gynoecium
    unit: pistil/carpel
    pistil/carpel has stigma, style and ovary.

(ii) Accessory whorl
-Corolla
unit: petals
colurful and fragrant for attraction of pollinating agents and secrete nectar

-Calyx
unit: sepals
usually green and photosyntheitic, provide protection to flower at bud stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is thalamus and pedicle

A

thalamus is the part that bears the flower
pedicle is the flower stalk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is a perianth

A

if calyx and corolla are fused it is called perianth. Its unit is tepals. found in family lilliaceae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

explain the structure of pollen grain

A

The pollen grain has two layers :
(i) intine- inner layer m/o pectin and hemicellulose
(ii) exine- outer layer m/o sporopollenin, which is the hardest material and cannot be broken by any acid, mechanical strength etc.

There are certain regions where the exine is absent called germpore. The pollen tube comes out through germpore.

Inside the pollen grain, there are 2 cells:
(i) Vegetative cell/tube cell: this is the larger cell which has the vegetative nucleus. this gives rise to pollen tube.
(ii) Generative cell- it is the smaller cell. When there is only one generative cell it is called 2 cell stage.
The generative cell undergoes mitossi and forms two cells. These are the two male gametes. This stage is called 3 -celled stage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

explain the structure of ovule

A

ovule has a mass of diploid cells called nucellus, which is covered by integuments or walls. There are two ends of the ovary, micropyle end which is open and opposite to it is chalazad end.
ANy one cell from nucellus will become megaspore mother cell and divide meiotically and form 4 megaspores. From this any one spore will become the functional female gamete while other 3 will degenerate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

describe the formation of embryo-sac

A

The functional megaspore (n) undergoes free nuclear division ( only karyokinesis) three times and forms 8 nuclei. Then there is rearrangement of nuclei and formation of wall leading to the formation of 1 egg cell, 2 synergids, 3 antipodal cells and 2 polar nuclei.
The egg cell and synergids are present at micropyle end. The synergids are at chalazad end, while polar nuclei are present in the centre.
This is called 7 celled & 8 nucleated female gametophyte or
embryo sac. The entire embryo sac is haploid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is filliform apparatus

A

these are present in the micropyle end of embryo sac and guide the entry of pollen tube.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is triple fusion

A

it is the fusion of secondary nucleus ( formed by fusion of 2 polar nuclei) and 1 male gamete.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

which has most developed:
(i) sprophyte
(ii) gametophyte

which has least developed
(iii) sporophyte
(iv) gametophyte

A

(i) angiosperm
(ii)moss

(iii) thallopyta
(iv)angio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

which is the last division to have:
(i) antheridia
(ii archegonia

A

(i) pteridophyte
(ii) gymnospemr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly