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Mistake Points

• The human skull has 22 bones, Skull and associated bones together consist of 29 bones but here the question is asking for the number of bones in the skull, therefore 22 will be correct.

Concept-

• The Skeleton system consists of a framework of bones, joints, cartilages, etc.
• The Skeleton system is divided into two parts-
• Axial skeleton- includes bones of the skull, upper and lower jaws, ribs, and vertebral column.
• Appendicular skeleton- involves the bone of legs and hand, pectoral and pelvic girdle.

Explanation-

• The skull is composed of two sets of bones- cranial and facial bones.

• Cranium bones = 8

• Frontal bone = 1

• Pariental bones = 2

• Occipital = 1

• Temporal bones = 2

• Sphenoid bone = 1

• Ethmoid bone = 1

• Facial bones = 14

• Nasal bones = 2

• Inferior turbinals = 2

• Vomer = 1

• Lacrimals = 2

• Zygomatic bones = 2

• Palatines = 2

• Maxillary = 2

• Mandible = 1

Therefore the total number of bones in the human skull is 22.

Additional Information

• Skull and associated bones consist of 29 bones.
• The associated bones are ear ossicles and hyoid bone.
• Ear ossicles - 3 + 3 = 6
• Malleus - 1 + 1 = 2
• Incus - 1 + 1 = 2
• Stapes - 1 + 1 = 2
• Hyoid = 1

The correct answer is centrosome.

• Plant cells are the basic unit of life in organisms of the kingdom Plantae. They have a true nucleus along with specialized structures called organelles that carry out certain specific functions.
• Centrosome 
• These are organelles that serve as the main microtubule-organizing centers for animal cells.
• It helps in cell division and stimulates the changes in the shape of the cell membrane by phagocytosis.
• They also maintain the chromosome number during cell division.
• Plant cells lack centrosomes. Plant cells have a cell wall, chloroplasts, and other specialized plastids, and a large central vacuole.

Important Points

• Plant cell walls are primarily made of cellulose. Cellulose fibers are long, linear polymers of hundreds of glucose molecules.

Additional Information

• Vacuoles 
• These are found in both animal and plant cells.
• They might store food or any variety of nutrients a cell might need to survive.
• They store waste products so the rest of the cell is protected from contamination.
• Plastids
• These are double-membrane organelle.
• These are responsible for the manufacturing and storing of food.
• There are different types of plastids with specialized functions. For example-Chloroplasts, Chromoplasts, Gerontoplasts, Leucoplasts, etc.
• It is not present in animal cell.

The correct answer is the Law of Conservation of Mass

Key Points

• Antoine-Laurent Lavoisier's most important contribution to chemistry in 1789 was the publication of his book
• Traité élémentaire de chimie (Elementary Treatise on Chemistry), which established the Law of Conservation of Mass and the first modern listing of known elements.
• Law of Conservation of Mass
• This law states that the total mass of reactants in a chemical reaction is equal to the total mass of products.
• Mass is conserved throughout the reaction.
• It established a fundamental principle in chemistry, emphasizing that matter cannot be created or destroyed, only transformed from one form to another.
• This law helped to develop chemical equations and stoichiometry, leading to more precise calculations in chemical reactions.​

Additional Information

• Law of Multiple Proportions
• This law states that when two elements combine to form more than one compound, the ratios of the masses of one element that combine with a fixed mass of the other element are in simple whole-number ratios.
• This law highlights that elements can combine in various ways to form different compounds, which led to the understanding of chemical formulas and molecular composition.
• It contributed to the development of atomic theory and provided evidence for the existence of atoms as distinct units in compounds.
• Law of Definite Proportions
• This law states that a chemical compound always contains its component elements in fixed ratio by mass, regardless of the sample size or source of the compound.
• It underscores the consistency and predictability of chemical composition in compounds, leading to a better understanding of chemical reactions.
• This law reinforced the concept of chemical identity and purity, influencing the classification of substances and the development of chemical nomenclature.
• Law of Conservation of Energy
• This law states that energy cannot be created or destroyed, only transformed from one form to another.
• It is a principle applicable to various fields, including physics and chemistry.
• This law emphasizes the interconnectedness of energy changes in physical and chemical processes, laying the groundwork for thermodynamics.
• It has profound implications in understanding chemical reactions, particularly in relation to energy changes, reaction kinetics, and thermodynamic stability.

The correct answer is 6.022 × 10²³.

Key Points

• The value of Avogadro's number is 6.022 × 10²³.
• It represents the number of atoms, molecules, or ions in one mole of a substance.
• The number is named after the Italian scientist Amedeo Avogadro.
• Avogadro's number is a fundamental constant in chemistry and is used in the calculation of the molar mass of substances.

Additional Information

• Mole:
• A mole is a unit of measurement used in chemistry to express amounts of a chemical substance.
• One mole contains exactly 6.022 × 10²³ elementary entities (atoms, molecules, ions, etc.).
• Molar Mass:
• The molar mass of a substance is the mass of one mole of that substance.
• It is expressed in grams per mole (g/mol).
• Avogadro's Law:
• Avogadro's Law states that equal volumes of gases, at the same temperature and pressure, contain the same number of molecules.
• This law is crucial for the concept of the mole and Avogadro's number.
• Applications of Avogadro's Number:
• Used in stoichiometry to convert between moles and number of particles.
• Essential for calculations in chemical reactions and determining molecular structures.

The correct answer is Retina.

Key Points

• The retina is a light-sensitive layer of tissue located at the back of the inner eye.
• It functions like the film in a camera, receiving the image formed by the lens.
• The retina converts light into electrical signals, which are sent to the brain via the optic nerve.
• Photoreceptor cells, namely rods and cones, are essential components of the retina, responsible for vision in low light and color vision, respectively.

Additional Information

• Cornea
• The cornea is the transparent, dome-shaped surface that covers the front of the eye.
• It helps to focus incoming light onto the retina.
• The cornea provides approximately 65-75% of the eye's total focusing power.
• Iris
• The iris is the colored part of the eye surrounding the pupil.
• It controls the size of the pupil and thus the amount of light that enters the eye.
• Pupil
• The pupil is the black circular opening in the center of the iris.
• It regulates the amount of light that enters the eye by expanding and contracting.
• Photoreceptors
• There are two main types of photoreceptors: rods and cones.
• Rods are responsible for vision in low light conditions, while cones are responsible for color vision and detail in bright light.

The correct answer is H₂SO₃

Key Points

• H₂SO₃ is the chemical formula for sulphurous acid.
• It is a weak and unstable acid formed by dissolving sulfur dioxide in water.
• Unlike sulfuric acid (H2SO4), sulphurous acid is not as commonly used in industrial applications due to its instability.
• It is primarily used as a reducing agent and in the bleaching of paper and textiles.
• Sulphurous acid is also used in the food and beverage industry as a preservative and disinfectant.

Additional Information

• Sulphurous acid is related to sulfur dioxide (SO₂), which is a significant air pollutant and can cause respiratory problems in humans.
• In aqueous solutions, sulphurous acid partially dissociates to form bisulfite (HSO^3-) and sulfite (SO₃^2-) ions.
• Handling of sulphurous acid should be done with care due to its corrosive nature and potential health hazards.
• It should be stored in a cool, well-ventilated area away from incompatible substances like strong oxidizing agents.

Rationale:

Correct Answer: 3) Ancylostomiasis

• Hookworm infection is primarily caused by Ancylostoma duodenale and Necator americanus.
• The disease resulting from these parasites is called Ancylostomiasis.
• Hookworms attach to the intestinal mucosa and feed on blood, commonly leading to iron deficiency anemia.

Why the other options are incorrect:

• 1) Elephantiasis – Caused by filarial worms (e.g., Wuchereria bancrofti), not by hookworm.
• 2) Ascariasis – Caused by Ascaris lumbricoides, a different type of roundworm.
• 4) Ascariasis and Architeuthis – Architeuthis refers to a giant squid and is not a disease; ascariasis is unrelated to hookworm infection.

Conclusion: Therefore, the correct disease caused by hookworm is Ancylostomiasis.

The correct answer is Meter per second (m/s).

Key Points

• The SI unit for speed is meter per second (m/s), which is the standard unit used in scientific measurements.
• Although speed limits on highways are commonly displayed in kilometers per hour (km/h) or miles per hour (mph) for practical reasons, the fundamental SI unit remains m/s.
• Speed is a measure of the distance traveled per unit of time, and the use of m/s is consistent with the metric system used globally.
• In everyday usage, different countries may prefer km/h or mph depending on regional standards, but m/s is universally accepted for scientific contexts.

Additional Information

• Speed in Different Units:
• 1 m/s = 3.6 km/h
• 1 m/s ≈ 2.237 mph

The correct answer is Smooth muscles.

Key Points

• The uterus, iris of the eye, and bronchi contain smooth muscles.
• Smooth muscles are involuntary, non-striated muscles found in various internal organs.
• These muscles are responsible for various involuntary movements in the body such as the contraction of the uterus during childbirth, adjustment of the iris in response to light, and regulation of airflow in the bronchi.
• Unlike skeletal muscles, smooth muscles are not under conscious control and are regulated by the autonomic nervous system.

Additional Information

• Striated muscles include skeletal muscles that are under voluntary control and are characterized by their striped appearance.
• Skeletal muscles are attached to bones and help in body movements.
• Cardiac muscles are specialized striated muscles found only in the heart, responsible for pumping blood throughout the body.
• Smooth muscles are also found in the walls of blood vessels, digestive tract, and other hollow organs.

The correct answer is AB Group.

Key Points

• AB Group can donate blood to only AB Group person.
• However, AB Group person is a universal acceptor since it has both kinds of antigens, which are Antigen A and Antigen B.
• People having a blood group of AB+ can accept blood from any person of any blood group.

Additional Information