Loss of water as droplets from the hydathodes is called:
Reason — Guttation is the loss of water as droplets along the margins of leaves through hydathodes.
Synthesis phase in the cell cycle is called so, because of the synthesis of more:
Reason — During the synthesis phase (S phase) of the cell cycle, the primary focus is on the synthesis of DNA. This phase is when the cell replicates its DNA in preparation for cell division.
While playing with his friends, Peter inserted a stick into his ear. He lost his hearing due to the rupture of:
- Ear drum
Reason — Rupture of ear drum leads to loss of hearing because ruptured ear drum cannot vibrate and transmit sound wave.
The prime source of Chlorofluorocarbons is:
- Vehicular emissions
- Refrigeration equipment
Reason — Chlorofluorocarbons (CFCs) are synthetic compounds widely used in refrigeration, air conditioning, aerosols, and foam production. They significantly contribute to ozone depletion in the Earth's stratosphere.
Oxygenated blood to heart is supplied by:
- Hepatic artery
- Coronary artery
- Renal artery
- Pulmonary artery
Reason — Coronary artery supplies oxygenated blood to heart for the functioning of cardiac muscles.
Assertion (A): There is frequent urination in summer than in winter.
Reason (R): In summer we lose a lot of water as sweat, so the kidneys reabsorb more water. Hence, urine formed is less in summer than in winter.
- Both A and R are True
- Both A and R are False
- A is True and R is False
- A is False and R is True
A is False and R is True
Reason — Urination is not so frequent in summers because more water is lost due to sweating
The age restrictions for marriage for boys and girls by law in India is:
- Boys 18 years, Girls 21 years
- Boys 17 years, Girls 16 years
- Boys 21 years, Girls 18 years
- Boys 20 years, Girls 17 years
Boys 21 years, Girls 18 years
Reason — The age restrictions for marriage for boys and girls by law in India is 21 years and 18 years, respectively.
Hari is fond of watching the fish in an aquarium. So, he set up an aquarium in his house. Along with a number of fresh water fish, he also placed a clown fish which is a salt water fish. After few hours, the clown fish was found dead and floating on water. This was due to:
Reason — The salt water fish have more salt in their body cells. When these fish are kept in fresh water the water flows into their cells due to endosmosis. Consequently their cells swell and they die.
The solvent used for dissolving chlorophyll while testing a leaf for starch is:
- Sodium hydroxide
- Lime water
- Ethyl alcohol
Reason — Ethyl alcohol is the solvent used for dissolving chlorophyll while testing a leaf for starch.
The structure related to storage and maturation of sperms in a human male is:
Reason — Epididymis is responsible for storage and maturation of sperms in a human male.
A sequence of DNA has 200 nitrogenous base pairs, of which 100 are Thymine-Adenine pairs. What is the number of Cytosine-Guanine pairs in this sequence:
Reason — The number of Cytosine-Guanine pairs in this sequence will be 100.
The stress hormone in plants which functions during a drought is:
- Abscisic acid
Reason — The stress hormone in plants which functions during a drought is abscisic acid. It helps in closure of stomata during drought condition.
Compressed natural gas (CNG) is proposed to be a better alternative to fossil fuel. Which of the following reasons makes it a better alternative?
P. Combustion leaves little or no residue
Q. Absence of Carbon in CNG
R. Easily available
- Only P
- Only Q
- Only P and R
- Only Q and R
Only P and R
Reason — Compressed natural gas (CNG) is proposed to be a better alternative to fossil fuel because its combustion is complete and do not release unburnt carbon particles or carbon monoxide.
The ground substance present in chloroplast is:
Reason — The ground substance present in chloroplast is stroma into which the thylakoids are embedded.
Lata wanted to cross the road. She looked on either side of the road and then walked across to the other side of the road.
Which of the following is / are involved in the process described above?
- Skeletal muscles
- Medulla Oblongata
- Only 3
- Only 1 and 3
- Only 1, 3 and 4
- Only 1, 2 and 3
Only 1, 2 and 3
Reason — Cerebrum controls intelligence and consciousness, cerebellum coordinates muscular activity and skeletal muscles help in the movement of muscles.
Name the following:
(a) The respiratory pigment in Erythrocytes.
(b) The tissue that transports manufactured food from the leaves to all the parts of the plant.
(c) The type of gene, which in the presence of a contrasting allele, is not expressed.
(d) The duct which carries urine from the urinary bladder to outside the body.
(e) The collective term for the protective membranes of the brain.
(c) Recessive gene
Arrange and rewrite the terms in each group in the correct order so as to be in a logical sequence beginning with the term that is underlined.
(a) Snake, Grass, Frog, Grasshopper
(b) Cochlea, Malleus, Pinna, Stapes
(c) Fibrin, Thrombin, Fibrinogen, Platelets
(d) Endodermis, Cortex, Xylem, Epidermis
(e) Morula, Foetus, Blastocyst, Embryo
(a) Grass → Grasshopper → Frog → Snake
(b) Pinna → Malleus → Stapes → Cochlea
(c) Platelets → Thrombin → Fibrinogen → Fibrin
(d) Epidermis → Cortex → Endodermis → Xylem
(e) Morula → Blastocyst → Embryo → Foetus
Fill in the blanks with suitable words:
The technical term for short sightedness is (a) ............... . This defect is caused because the eyeball is (b) ............... from front to back or the lens is too (c) ............... . It can be corrected by using a suitable (d) ............... lens. The power of the lens is mentioned in (e) ............... .
The technical term for short sightedness is (a) myopia . This defect is caused because the eyeball is (b) lengthened from front to back or the lens is too (c) curved . It can be corrected by using a suitable (d) concave lens. The power of the lens is mentioned in (e) minus.
Choose the odd one out from the following terms and name the category to which the others belong:
(a) Newspapers, Vegetable peels, Electric bulbs, Animal excreta
(b) Renal pelvis, Renal artery, Renal Cortex, Renal medulla
(c) Urochrome, Urea, Keratin, Uric acid
(d) Oval window, Cochlea, Auditory canal, Round window
(e) ADH, TSH, ACTH, NADP
(a) Odd one: Electric bulbs
Newspapers, Vegetable peels, Animal excreta : Biodegradable waste
(b) Odd one: Renal artery
Renal pelvis, Renal Cortex, Renal medulla : Parts of Kidney
(c) Odd one: Urochrome
Urea, Keratin, Uric acid : Nitrogenous waste
(d) Odd one: Auditory canal
Oval window, Cochlea, Round window : Parts of inner ear
(e) Odd one: NADP
ADH, TSH, ACTH : Hormones
Match the items given in Column I with the most appropriate ones in Column II and rewrite the correct matching pairs.
|Column I||Column II|
|Number of autosomes in man||Nephrons|
|Column I||Column II|
|Number of autosomes in man||44|
The gene of red hair is recessive to the gene for black hair. What will be the hair colour of a person if he inherits a gene for red hair from his mother and a gene for black hair from his father?
The colour of hair of that person will be black because the dominant gene (black) will express itself.
State Mendel's Law of Dominance.
Law of Dominance — Out of a pair of contrasting characters present together, only one is able to express itself while the other remains suppressed. The one that expresses is the dominant character and the one that is unexpressed is the recessive one.
What are Homologous chromosomes?
The chromosomes that contain same genes in same order along their chromosomal arm are said to be homologous. They pair with each other during cell division.
Differentiate between Phenotype and Genotype.
|The observable characteristics which are genetically controlled is known as phenotype.||Set of genes present in any organism is known as its genotype.|
|Can be determined by observation.||Can be determined by genotyping method.|
|It consists of only expressed genes.||It is formed by expressed and unexpressed genes.|
Draw a neat, labelled diagram of a duplicated chromosome.
Labelled diagram of a duplicated chromosome is given below:
Mention the exact location of Corpus callosum.
Corpus callosum is located between two cerebral hemispheres.
What are the two hormones secreted by Corpus luteum?
The two hormones secreted by Corpus luteum are progesterone and estrogen.
Differentiate between Menarche and Menopause.
|It is the onset of menstruation in a young female at about the age of 13 years.||It is the permanent stoppage of menstruation in females at about the age of 45 years.|
What is the significance of placenta in the growth of foetus?
The significance of placenta in the growth of foetus are:
- Placenta provides the foetus with oxygen and nutrients.
- Placenta also removes carbon dioxide and waste products of the foetus.
Draw a neat, labelled diagram of a human gamete that has the sex chromosome Y.
Sperm is the human gamete that can have sex chromosome Y. Its labelled diagram is shown below:
Explain the term — Photosynthesis.
Photosynthesis is the process by which living plant cells, containing chlorophyll, produce food substances (glucose and starch), from carbon dioxide and water, by using light energy and release oxygen as a by-product.
Write the overall chemical equation of Photosynthesis.
Balanced chemical equation representing the process of photosynthesis is given below:
A potted plant having variegated leaves was exposed to sunlight for 3 hours. One of the leaves was plucked and tested for starch. What will be your observation after the starch test?
After conducting the starch test, the green leaf portion turns blue, indicating starch presence, confirming photosynthesis due to chlorophyll. Non-green parts lack chlorophyll, don't photosynthesize, and show no starch-related colour change.
The initial food prepared by a green plant is A, which is later converted to food B by polymerization. Name food A and food B.
A → Glucose
B → Starch
Study the diagram given below and answer the questions that follow:
(a) Name the gas released when the setup was placed in sunlight.
(b) Give an example of an aquatic plant that can be used in the above experiment.
(c) What will happen if a pinch of Sodium bicarbonate is added to the water?
(c) If a pinch of Sodium bicarbonate is added to the water the amount of carbon dioxide in water will increase. This will increase the rate of photosynthesis and hence the rate of evolution of oxygen will also increase.
Give the exact location of genes.
The exact location of gene is on the chromosomes.
Differentiate between Karyokinesis and Cytokinesis.
|It is the division of the nucleus.||It is the division of the cytoplasm.|
|It is the first division.||It occurs after karyokinesis.|
|It results in the formation of two nuclei.||It results in the formation of two daughter cells.|
Mention two significant features of the stage Anaphase during Mitosis.
Two significant features of the stage Anaphase during Mitosis are:
- Centromere attaching the two chromatids divides or splits.
- A furrow starts in the cell membrane at the middle in animal cell.
How many daughter cells are formed at the end of Mitosis and Meiosis?
Mitosis leads to formation of two daughter cells. Meiosis forms four daughter cells.
Study the diagram given below and answer the questions that follow:
(a) Name the phenomenon depicted by the shoot in the above diagram.
(b) Which plant hormone plays an important role in the above movement?
(c) Name one stimulus which gives a positive response for the roots but negative response for the shoot.
(a) Phototropism is the phenomenon depicted by the shoot in the given diagram.
(b) Auxin is the plant hormone that plays an important role in phototrophic movement.
What is the scientific name for man?
Homo sapiens sapiens
What are vestigial organs? Give one example.
Vestigial organs are those organs that have ceased to be of any use to the possessor but still persist generation after generation in a reduced form. Example - Vermiform Appendix.
State two structural differences between an artery and vein.
|Arteries have thick and muscular walls.||Veins have thin and less muscular walls.|
|Have narrower lumen.||Have wider lumen.|
Mention any two features of the Cro-Magnon man.
Two features of the Cro-Magnon man are:
- Large skull, broad face, rounded forehead and a prominent chin.
- Cranial capacity 1450-1600 cm3.
Study the picture given below and answer the questions that follow:
(a) Name the category of waste that is being disposed.
(b) Give an example of such a waste.
(c) Are they hazardous to humans and animals? Give a suitable reason to justify your answer.
(a) Biomedical waste
(c) Biomedical waste, if not disposed properly can cause harm to humans and animals by spreading microorganisms and diseases. They also have different chemicals which can be toxic to humans, animals and soil microorganisms.
Osmosis is the movement of water molecules from their region of higher concentration (dilute solution or with a lower solute concentration) to their region of lower concentration (concentrated solution or with a higher solute concentration) through a semi permeable membrane.
Name the two sensory cells in retina meant for light adaptation.
Rod cells and cone cells are responsible for light adaptations.
Mention one function each for — Cerebrum and Cerebellum.
Cerebrum — Intelligence and memory.
Cerebellum — Coordinates muscular activity.
State any two objectives of Swachh Bharat Abhiyan.
Two objectives of Swachh Bharat Abhiyan are:
- To eliminate open defecation through the construction of individual, cluster and community toilets.
- To clean the streets, roads and infrastructure of the countries cities and towns.
Given below is the diagram of human blood smear. Answer the questions that follow:
(a) Mention one structural difference between 1 and 2.
(b) What is the function of part 3?
(c) Name the part labelled 4.
(a) The parts labelled 1 and 2 are:
- 1 → Red Blood Cell (RBC)
- 2 → White Blood Cell (WBC)
One structural difference between red blood cells and white blood cells is:
|Red Blood Cells||White Blood Cells|
|Red blood cells are minute biconcave disc-like structures.||White blood cells are amoeboid and can produce pseudopodia with which they can squeeze through the walls of the capillaries into the tissues.|
(b) Part 3 is blood platelet. Its main function is to initiate blood clotting.
(c) Part 4 is blood plasma.