AHSEC| CLASS 11| BIOLOGY| SOLVED PAPER - 2017| H.S.1ST YEAR
2017
Biology
(Theory)
Times: 3 hours
Full marks: 70
Part - I (Botany)
1. Who discovered plant nucleus? 1
Ans:- Robert Brown.
2. Who proposed transpiration pull and cohesion of water
theory? 1
Ans:- Dixon in 1914.
3. What is the full form of EMP pathway? 1
Ans:- Embden Meyerhof and Parnas.
4. Define autotrophic and heterotrophic plants with
examples. 2
Ans:- Autotrophic plant
– Algae.
Heterotrophic plants
– Fungi.
5. Draw and label the moss capsule. 2
Ans:-
6. Mention the four major characters of prokaryotic
cell. 2
Ans:- The characteristics of cells are as follows:
(i) Their size
varies from 0.1 millimeter to 10 millimeter.
(ii) they are
doing not have membrane-bound organelles.
(iii) they need
single circular desoxyribonucleic acid as genetic material and plasmids.
(iv) They
contain mesosomes for respiration.
7. Write the specific roles of IAA. 2
Ans: Root and shoot development takes place in the
plant cell thanks to this hormone.
8. Mention two examples each of long-day and short-day
plants. 2
Ans:- Long-day plants – Spinash
and lattuce.
Short-day
plants – Tomato and Corn.
9. Differentiate between dicotyledonous and
monocotyledonous plants with examples.
2
Ans:- (i) Dicotyledonous embryo has two cotyledons
while monocotyledon has one cotyledon.
(ii) The leaf
vein is reticulated while the leaf vein is parallel.
(iii) petals in
multiples of four or five while petals in multiples of three.
(iv) Taproot
system, fibrous root.
10. Define inflorescence. Explain the chief differences
between racemose and cymose inflorescences with examples. 1+2=3
Ans: The arrangement of flowers on the axils of
flowers is called inflorescence.
Racemose
inflorescence:
(i) The
principal axis remains in motion.
(ii) The
arrangement of flowers is in acropetal succession.
(iii) Flowers
are not aggregates.
Cymose
inflorescence:
(i) The
principal axis ends in a flower.
(ii) Flowers
develop in basipetal succession.
(iii) Flowers
are in the family.
11. Write the structure and functions of mitochondria
with diagram. 1+1+1=3
Ans:- Each mitochondrion is a double membrane-bound
structure in which the outer membrane is an inner membrane that clearly divides
its lumen into two aqueous compartments, i.e., the outer compartment and the
inner compartment. The inner compartment is called the matrix. The outer
membrane forms a continuous limiting range of organelles. The inner membrane
forms several insertions at the edge of the matrix called cristae. Christs
increase the surface area. The two membranes have their own specific enzymes
that are associated with mitochondrial function. Mitochondria are the sites of
aerobic respiration. They produce cellular energy in the form of ATP, so they
are called the 'power house' of the cell. The matrix also contains a single
circular DNA molecule, some RNA molecules, ribosomes (70S) and components
necessary for the synthesis of proteins. Mitochondria divide by fission.
12. What is transpiration? Discuss the role of stomata in
transpiration. 1+2=3
Ans:- Transpiration is the process of movement of
water through a plant and its evaporation from aerial parts such as leaves,
steam and flowers.
Water in plants
is temporary. Less than 1 percent of the water that reaches the leaves is used
for photosynthesis and plant growth. Most of it is lost through stomata in the
leaves. This loss of water is known as transpiration.
13. What is tissue system? Write the different types of
vascular bundles found in the angiospermic plants with examples. 1+4=5
Ans: Plants have a high level of structure called
plant tissue system. Plant tissue system consist of –
(i) epidermal
tissue system
(ii) ground
element tissue system,
(iii) vascular
and conductive tissue system.
The different
types of vascular bundles found in angiospermic plant are:
(i) Xylem:
Xylem acts as a conducting tissue for water and minerals from the roots to the
stem and leaves. It also provides mechanical strength to plant parts. It is
composed of four different types of elements, namely, tracheids, vessels, xylem
fibers and xylem parenchyma.
(ii) Phloem:
Phloem carries food material usually from leaves to other parts of the plant.
Phloem sieve in angiosperms is composed of tube elements, companion cells,
phloem parenchyma and phloem fibers.
14. Define photosynthesis. Write the prime
differentiating characters of cyclic and non-cyclic photophosphorylation’s. 1+2+2=5
Ans: The process by which green plants and some other
organisms use sunlight to synthesize nutrients from CO2 and water.
Cyclic
Photophosphorylation:
(i) Includes
only photo system I.
(ii) The
electron removed from the chlorophyll is returned to the same chlorophyll in a
cyclic manner.
(iii) No
photolysis of water takes place and O2 is not evolved.
(iv) It
synthesizes only ATP.
Non-cyclic
Photophosphorylation:
(i) Both
photosystem I and II are involved.
(ii) The
electrons removed from chlorophyll never return to the same chlorophyll.
(iii) Photolysis
of water takes place, O2 is evolved.
(iv) It is ATP
and NADPH2. synthesizes both
Or
Describe the
external and internal factors affecting in photosynthesis. 5
Ans: When
discussing light as a factor influencing photosynthesis, we need to distinguish
between light quality, light intensity and duration of exposure to light.
Carbon dioxide is
the major limiting factor for photosynthesis. The concentration of CO2
in the atmosphere is very low (between 0.03 and 0.04 percent). An increase of
up to 0.05 percent in concentration can increase the CO2 fixation
rate; Levels beyond this can be harmful in the long term.
Being enzymatic,
the dark reaction temperature is controlled. Although light reactions are also
sensitive to temperature, they are affected to some extent. C4
plants respond to higher temperatures and show higher rates of photosynthesis
whereas C3 plants have much lower temperatures.
Although water is
one of the reactants in the reaction of light, the effect of water as a factor
is greater on the plant than directly on photosynthesis. The pressure of the
water causes the stomata to close, reducing the availability of CO2.
In addition, weight stress also causes wilting of leaves, thus, the surface
area of leaves and their metabolic activity are also reduced.
[COMING SOON]
BIOLOGY SOLVED PAPERS PAGE LINK - Click here
BUY E-BOOK (PDF FILE)
[TO SEE FULL SOLUTION]
(Chapter wise Notes, Exam Question Papers solved, MCQ solved) [ARTS, COMMERCE, SCIENCE]
|
DOWNLOAD PAGE LINK:-CLICK HERE |
AHSEC PAGE LINK - CLICK HERE
Also Read: