GENERAL SCIENCE -PAPER-II BY DGE
BIOLOGICAL SCIENCE (ENGLISH VERSION)
Time : 2 Hours Max. Marks : 50
SECTION-I (6
× 1 = 6 M)
1. Name the hormone responsible for
phototropism in plants.
Ans: Auxin
2. Write a slogan to stop female foeticide.
Ans: Save the Girl Child, Save the Nation.
3. Transfer of characters from parents to
progeny is known as
Ans: Heredity
4. Olfactory receptors detect
A) touch B) taste C) smell D) light ( )
Ans: C) smell
5. Identify the type of asexual reproduction
in the given picture.
Ans: Binary fission in Amoeba
6. Two species, A and B, live in the
same environment.
Species A shows a wide range of variations among its individuals.
Species B has individuals with very similar traits.
Which species is more likely to survive if the environment changes suddenly?
Ans: Species A (because it has more variations)
SECTION – II (4 × 2 = 8
M)
7. Explain the digestion of fats in the human
beings.
- Bile from
the liver breaks fats into tiny droplets (emulsification).
- Pancreatic
and intestinal lipase enzyme converts these droplets into fatty
acids and glycerol.
- These are
then absorbed in the small intestine.
8. Read the table and answer the questions.
|
S. No. |
Hormone |
Endocrine Gland |
Function |
|
1 |
Thyroxine |
Thyroid gland |
Regulates metabolism for body growth |
|
2 |
Estrogen |
Ovaries |
Development of female sex organs; regulates
menstrual cycle |
A. Which gland secretions associated with the
changes that occurs during puberty in females?
- Ovaries secrete estrogen.
- Estrogen
causes physical and reproductive changes during puberty.
B. What is the function of the thyroxin
hormone?
- Thyroxine
helps regulate metabolism.
- It controls
energy production and supports normal body growth.
9. What precautions do you follow to protect
yourself from the diabetes?
- Exercise
regularly and maintain a healthy weight.
- Eat a
balanced diet with low sugar and avoid junk foods.
- Go for
regular health check-ups and monitor blood sugar.
10. Define the trophic level and mention the
different trophic levels in a food chain.
- A trophic
level is the feeding level in a food chain.
- Trophic
levels: Producers → Primary consumers → Secondary consumers → Tertiary
consumers.
- They show
the flow of energy from one level to another.
SECTION – II (5 × 4 = 20 M)
11. What are the components of the transport
system in human beings? What are the functions of these components?
- The
components are heart, blood, and blood vessels (arteries, veins,
capillaries).
- The heart
pumps blood throughout the body.
- Blood transports oxygen, nutrients, hormones,
and waste materials.
- Arteries carry blood away from the heart; veins
bring blood back to the heart.
- Capillaries help in exchange of gases and nutrients.
12. Draw a neat labelled diagram of the
following
A) Nephron
(or)
B) Process of fertilization in the flower
13. People in your locality are throwing
plastic bags into the nearby water streams. What environmental problems may
arise? How will you create awareness?
- Plastic bags
block water flow, cause water pollution, and kill aquatic animals.
- They create
breeding grounds for mosquitoes and lead to health problems.
- I will
conduct awareness campaigns and explain the dangers of plastic use.
- Encourage
people to use cloth bags and place dustbins near water streams.
- Involve
local leaders and school students for community clean-up drives.
14. Give some suggestions to control high
blood pressure and maintain a healthy heart.
- Reduce salt
intake and avoid fried/junk foods.
- Exercise or
walk for at least 30 minutes daily.
- Maintain a
healthy body weight and avoid smoking/alcohol.
- Practice
stress-relief methods like yoga and meditation.
- Go for
regular blood pressure check-ups.
15. Which is the better method in waste
disposal – ‘burning’ or ‘composting’? Justify.
- Composting is better because it converts waste into
useful manure.
- Burning
releases harmful smoke and increases air pollution.
- Composting
improves soil fertility and supports plant growth.
- It is safe,
eco-friendly, and cost-effective.
- Burning
wastes natural resources and harms human health.
SECTION-IV (2 x 8 = 16 M)
16. A)
Explain the lab activity to prove that carbon dioxide is necessary for
photosynthesis
AIM : To
show that carbon dioxide (CO₂) is needed for photosynthesis.
MATERIALS: Two
potted plants, bell jars, potassium hydroxide (KOH), Vaseline, iodine.
PROCEDURE
1.
Keep both plants
in the dark for 2–3 days (to remove starch).
2.
Place each plant
under a separate bell jar.
3.
Keep KOH
inside one bell jar. KOH absorbs CO₂.
4.
Seal both jars
with Vaseline so air cannot enter.
5.
Keep them in
sunlight for a few hours.
6.
Pluck one leaf
from each plant and test with iodine.
OBSERVATION
- Plant with
KOH: leaf does not turn blue-black.
- Plant without
KOH: leaf turns blue-black.
RESULT
- The plant
without CO₂ cannot make starch.
- So, carbon
dioxide is necessary for photosynthesis.
16 B) Explain Lab activity what you followed
in your school to observe spore formation in Rhizopus.
Aim:
To observe the growth of Rhizopus on bread.
Materials:
Moist bread slice, petri dish, magnifying glass
Procedure:
1.
Place a moist bread slice in a cool, dark
place for two days.
2.
Observe the bread under a magnifying glass.
Observation:
A white mass of mold (Rhizopus) grows on the bread, later turning black.
Conclusion:
Rhizopus mold produces black sporangia that release spores for reproduction.
17.A) Compare and contrast nervous and
hormonal mechanisms for control and coordination in animals.
|
Nervous Mechanisms |
Hormonal Mechanisms |
|
Nervous
system (brain, spinal cord, and nerves) |
Endocrine
system (glands and hormones) |
|
Electrical
impulses (neurons) |
Chemical
messengers (hormones in the blood) |
|
Very
fast (milliseconds) |
Slow
(minutes to hours) |
|
Short-term
(immediate but brief) |
Long-term
(effects last longer) |
|
Muscle
contraction, reflex actions |
Regulation
of metabolism, growth, and reproductive functions |
|
Immediate
body actions (reflexes, movement, sensory input) |
Gradual
processes (growth, puberty, metabolism) |
|
Localized
and quick |
Systemic
(affects the entire body) |
|
Easily
reversible |
Usually
takes longer to reverse effects |
|
Reflex
actions, voluntary movements |
Release
of insulin, growth hormone, adrenaline |
17 B) "The father is responsible for
determining the sex of the baby, not the mother"- How would you analyse
this statement?
- Mother
(female): Has XX
sex chromosomes.
→ She produces only X-type ova. - Father
(male): Has XY
sex chromosomes.
→ He produces two types of sperm:
X-sperm
and Y-sperm
Two possibilities
- If X-sperm
wins → girl
- If Y-sperm
wins → boy
1.
X-sperm +
X-ovum → XX (Girl baby)
2.
Y-sperm +
X-ovum → XY (Boy baby)
So,
the type of sperm—X or Y—is the deciding factor.
Hence, the father is responsible for
determining the sex of the baby
