MARKING SCHEME
CENTRE FOR ADVANCEMENT OF STANDARDS IN EXAMINATIONS
(GEMS ASIAN SCHOOLS)
COMMON REHEARSAL EXAMINATIONS 2025-26
Grade: X
Subjects: Science (086)
Qn. Value Points Points Total
No wise Marks
marks
1 B. Holozoic – Lion; Saprophytic – Mushrooms; Parasitic – 1 1
Tapeworm
2 B. Carbon dioxide and water 1 1
3 D. Both C and D 1 1
4 C. Nervous system is fast but short-lasting; endocrine system is 1 1
slow but long-lasting.
5 C. TtWW 1 1
6 B. S Q R P 1 1
7 B. Grass → Mouse → Eagle 1 1
8 A. Both A and R are true, and R is the correct explanation of A. 1 1
9 C. A is true but R is false. 1 1
10 a. The leaf of plant X turned blue‑black because it accumulated 1
starch. 2
b. Carbon and energy requirements of the autotrophic organism 1
are fulfilled by photosynthesis.
11 The separation of the right side and the left side of the heart is ½
useful to keep oxygenated and deoxygenated blood from mixing. ½ 2
Such separation allows a highly efficient supply of oxygen to the ½
body. This is useful in animals that have high ½
energy needs/which constantly use energy to maintain their body
temperature.
OR
Diffusion alone is inadequate in Giant Sequoias because the large ½
distances between roots and leaves make diffusion too slow to ½
supply water, nutrients, and sugars. 2
The xylem moves water and minerals obtained from the soil. The ½
phloem transports products of photosynthesis from the leaves. ½
1
, 12 Excess generation of biodegradable wastes can be harmful as – Its 1
decomposition is a slow process leading to production of foul
smell and gases.
It can be the breeding ground for germs that create unhygienic 2
1
conditions. (any two points)
13 (i) The plant is Mimosa pudica (commonly called the Touch-me- ½
not plant or Sensitive plant). The type of movement shown is
movement without involving growth, also called nastic
½
movement.
(ii) The leaves fold due to a rapid change in turgor pressure within 1
3
specialized cells at the base of the leaflets, triggered by the touch
stimulus, which causes water to move out of the cells, making 1
them flaccid and leading to the drooping and folding of the leaves
14 (i) Mother- Dd Father- Dd 1
Probability of a child with dimples- 75% ½
(ii) Yes, the child can have dimples ½ 3
If the child with genotype DD/Dd marries one with genotype dd
DD x dd
Dd x dd, in both cases the offspring can have genotype Dd 1
( dimple)
15 A.
Feature Renal Artery Renal Vein
Carries blood ½
Carries blood from the
(i) Direction of from the heart
kidneys to the heart ½
blood flow (aorta) to the 4
(inferior vena cava).
kidneys.
Blood is ½
oxygenated, Blood is deoxygenated,
contains more has less urea and wastes ½
(ii) Composition
urea, salts, and (as filtration has occurred),
of blood
other waste but is richer in carbon
materials to be dioxide.
filtered.
OR
B. Glomerulus in Bowman’s capsule →Tubular part →Collecting
Duct →Ureter →Urinary Bladder → Urethra →Urination.
2
CENTRE FOR ADVANCEMENT OF STANDARDS IN EXAMINATIONS
(GEMS ASIAN SCHOOLS)
COMMON REHEARSAL EXAMINATIONS 2025-26
Grade: X
Subjects: Science (086)
Qn. Value Points Points Total
No wise Marks
marks
1 B. Holozoic – Lion; Saprophytic – Mushrooms; Parasitic – 1 1
Tapeworm
2 B. Carbon dioxide and water 1 1
3 D. Both C and D 1 1
4 C. Nervous system is fast but short-lasting; endocrine system is 1 1
slow but long-lasting.
5 C. TtWW 1 1
6 B. S Q R P 1 1
7 B. Grass → Mouse → Eagle 1 1
8 A. Both A and R are true, and R is the correct explanation of A. 1 1
9 C. A is true but R is false. 1 1
10 a. The leaf of plant X turned blue‑black because it accumulated 1
starch. 2
b. Carbon and energy requirements of the autotrophic organism 1
are fulfilled by photosynthesis.
11 The separation of the right side and the left side of the heart is ½
useful to keep oxygenated and deoxygenated blood from mixing. ½ 2
Such separation allows a highly efficient supply of oxygen to the ½
body. This is useful in animals that have high ½
energy needs/which constantly use energy to maintain their body
temperature.
OR
Diffusion alone is inadequate in Giant Sequoias because the large ½
distances between roots and leaves make diffusion too slow to ½
supply water, nutrients, and sugars. 2
The xylem moves water and minerals obtained from the soil. The ½
phloem transports products of photosynthesis from the leaves. ½
1
, 12 Excess generation of biodegradable wastes can be harmful as – Its 1
decomposition is a slow process leading to production of foul
smell and gases.
It can be the breeding ground for germs that create unhygienic 2
1
conditions. (any two points)
13 (i) The plant is Mimosa pudica (commonly called the Touch-me- ½
not plant or Sensitive plant). The type of movement shown is
movement without involving growth, also called nastic
½
movement.
(ii) The leaves fold due to a rapid change in turgor pressure within 1
3
specialized cells at the base of the leaflets, triggered by the touch
stimulus, which causes water to move out of the cells, making 1
them flaccid and leading to the drooping and folding of the leaves
14 (i) Mother- Dd Father- Dd 1
Probability of a child with dimples- 75% ½
(ii) Yes, the child can have dimples ½ 3
If the child with genotype DD/Dd marries one with genotype dd
DD x dd
Dd x dd, in both cases the offspring can have genotype Dd 1
( dimple)
15 A.
Feature Renal Artery Renal Vein
Carries blood ½
Carries blood from the
(i) Direction of from the heart
kidneys to the heart ½
blood flow (aorta) to the 4
(inferior vena cava).
kidneys.
Blood is ½
oxygenated, Blood is deoxygenated,
contains more has less urea and wastes ½
(ii) Composition
urea, salts, and (as filtration has occurred),
of blood
other waste but is richer in carbon
materials to be dioxide.
filtered.
OR
B. Glomerulus in Bowman’s capsule →Tubular part →Collecting
Duct →Ureter →Urinary Bladder → Urethra →Urination.
2
