BIOLOGY PRACTICAL- Spotting A,B,C.

 


XII BIOLOGY PRACTICAL- Q.4- Spotting:

 (Identify the following 10 spots-)10 Marks

SpotA:

Name the plant and write on floral adaptations for type of pollination

[(i) Wind pollination, (ii) Insect pollination]

OR

Controlled pollination (emasculation, bagging and bagging with tagging)

SpotB:

Anyone experiment from plant physiology.

(i) Rate of transpiration by four leaf experiment.

 (ii) hnbibition of seedslRaisins

(iii) Separation of plant pigments by paper chromatography

Spot C:

Identify the plant and comment on its morphological adaptations in aquatic/xeric habitats

Spot D:

 Permanents slide ofT.S. testislT.S. of ovaryN.S. of blastula.

Spot E:

 Comment of the given pedigree chart.

Spot F:

 Identify the disease and comment on control measures.

Spot G:

Identify the stage of meiosis in the given slide.

Spot H:

 Identify the animal and comment on its xeric adaptations/aquatic adaptations.

Spot I:

Name the part/parts indicated by marker in the model/chart and enlist their functions(ovule V.S.)

OR

Identify the slide on Barr body.

Spot J:

 Comment on the given pedigree chart with respect to the inheritance of trait.

 

OR

Comment on the specimen with respect to eye and wing in the given specimen (Drosophila).

OR

Identify the type of cell marked and mention its features/functions (blood profile)

ANS - (A)floral adaptations for wind pollination. Maize plant,                                                                   

1) Flowers are small, numerous and inconspicuous.

2) They are unisexual, odourless and nectarless .

3) Male inflorescence is terminal while female inflorescence is monoecious.

4) Perianth reduced to lodicules. Stigma and anthers protrude outside.  

 

ANS- A) Floral adaptations for Insect pollination in   Salvia plant. 

Flowers  are bisexual attractive and have bright coloured petals.   

The nectar and the nectar glands are present in flower and they are situated in such a way that when insect tries to reach the nectar glands,  There are two stamens located at the mouth of corolla tube.

Figures and photographs Stamens of Salvia show short filaments and elongated divaricate connective.The fertile anther lobe is at the tip of longer arm. 

 When insect enters the flower it lodges on the lower sterile lobe, pushes it and as a result upper fertile lobe bends down. fused together, showing long style with bifid, hairy stigma.

Visitor insect lands on the lower lip of corolla and then pierces its proboscis right up to the nectar gland.

 In doing so, sterile anther lobes are pushed and fertile anther lobes bend down, dusting the body of insect with pollen grains are ornamented.  

When gynecium matures, style elongates and stigma bend down and thus gets positioned across the path of visitor insect.    

                                                                                                                                                                                             

ANS- A)  Emasculation:

1 )The removal of stamens from  anther  is called emasculation.

2)For emasculation flower buds are opened and stamens are removed by forceps.

3)For emasculation a plant bearing bisexual flower.     

4)which behaves as a female parent is selected



Answer: A) It is  step of hybridization -bagging .
1) It is step of hybridization

2)emasculated flower is enclosed in a polythene bag. This process is called bagging

3)Bagging is followed by tagging in which a tag bearing the name of the plant, date of emasculation, etc. it is tied to the emasculated plant.



Answer:A

  1. The given spot is a step of hybridization technique –tagging.
  2. •A tag is tied to the bag of emasculated flower.
  3.  •This is called tagging.
  4. •The tag carries brief informationabout •the names of selected parent varieties and
  5. •the day, date and time of anthesis, emasculation and actual crossing.


  • B)  Rate of  transpiration by four leaf experiment.  
  • A- leaf, which is vaselined on its both the surfaces, looks fresh and green, as no surface transpires.     
  • B- leaf is vaselined on its lower surface and transpiration takes place only from the upper surface which is negligible. This leaf also remains turgid and green like the A leaf. 
  • C- leaf is vaselined on its upper surface, which contains less number of stomata or no stomata.   The transpiration takes place from the lower stomatal surface, and the leaf shrivels to a large extent.
  • D -leaf is not vaselined and both the surfaces transpire freely releasing much water.  This experiment proves that the rate of stomatal transpiration is fairly higher than the cuticular transpiration.

B) . Identify and comment on. Imbibition  of  seeds Raisins.

 The seeds of raisins  soaked in water show change in their volume showing swollen  structure and seed coat/ raisins shows softening

The seeds swell up when soaked in water due to imbibition and endosmosis. 


B)  Separation of plant pigments by paper chromatography

On the strip we can observe the separation of photosynthetic pigments as bands of differ colours in a particular sequence.

From loaded spot up to the top the sequence is; chlorophyl (yellowish green), chlorophyll-a (bluish green), xanthophylls (yellow) and carotene (orange)



C) Answer:

The given spot is a xeric plantCalotropisprocera.

It is non-succulent, drought enduring, wild shrub of arid, desert and waste land.

Leaves and young branches are covered by a mealy coating along with hair which acts as insulating covering.

The leaves are thick and somewhat leathery.

The plant possess latex.


C) Its morphological adaptations in xeric habitats.-Acacia arabica. 

(1) It is a non-succulent xerophyte, It is drought enduring.

2) It is a small sized tree which grows wild in arid habitats.

(3) It is well branched. The older parts of stem are covered by thick bark.

(4) Leaves are bipinnately compound. Leaflets are small in size.

(5) Stipules are modified into spines to prevent browsing,


C) its morphological adaptations in xeric habitats. In Opuntia dillenii.

1. It is a succulent (drought resisting or enduring) xerophyte.  

2. The stem is flattened, jointed, green and is called phylloclade. It takes over the function of photosynthesis because the leaves are modified into spines Branch .

3. The stem i.e. phylloclade is fleshy succulent due to presence of mucilage that retains water4.Phylloclades are with many nodes (areoles) and internodes.  

4.The areoles have one or more spines which represent the modified leaves of axillary branch.

 

 (C) morphological adaptations. aquatic plants= Hydrilla

 1) Hydrilla is a submerged hydrophyte rooted at the bottom.

(2) Roots are poorly developed. They are unbranched.  . Root hairs are  absent. 

3) The leaves are small in size, linear and thin, without stomata

4) The arrangement of leaves is in whorls which allows free movement of water currents     

C) Answer:

The given spot is a aquatic plant –Eichhornia. 

It is a free floating hydrophyte. 

It grows in fresh water ponds, lakes, etc. 

The stem is short and spongy due to the aerenchyma that stores air.

It is the offset that grows prostrate just below the water surface.   

It serves as means for vegetative reproduction.  

Leaves shows swollen, spongy, petioles and arise in clusters at node.

They have waxy coating in addition to cuticle to prevent wetting and rottening.  

Adventitious roots are also produced in clusters at nodes.

They act as balancers.

They have root pockets. Root hair are absent

C) its morphological adaptations in aquatic habitats in  Typha .   

  Answer:

The given spot is a aquatic plant –Typha.

It is an amphibious and anchored hydrophyte.

It grows in marshy places or shallow waters.

The stem is rhizome with adventitious roots and emergent leaves, coming out oswater surface.

The leaves are long, linear, soft, spongy, thick and sub-cylindrical. They have aerenchyma tissue.

They show the presence of mechanical tissue so that they can stand erect.

They have cuticle and stomata on the emergent part.

Post a Comment

please do not enter any span link in the coment box

Previous Post Next Post