General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
91
Which hormone, produced by the pancreas, acts to lower blood glucose levels?
Answer:
Insulin
Insulin is secreted by the beta cells of the Islets of Langerhans in the pancreas. It facilitates the uptake of glucose by body cells and the conversion of glucose to glycogen in the liver, effectively lowering blood sugar levels.
92
Which component of the lymphatic system serves as a filter for trapping pathogens and foreign particles?
Answer:
Lymph nodes
Lymph nodes are small, bean-shaped structures distributed along lymphatic vessels. They contain high concentrations of lymphocytes and macrophages that filter the lymph, identifying and destroying bacteria, viruses, and cancer cells.
93
The sliding filament theory explains the contraction of which type of tissue?
Answer:
Muscle tissue
The sliding filament theory describes how actin and myosin filaments within the sarcomere of a muscle fiber slide past each other to shorten the muscle and generate force during contraction.
94
Which organ of the urinary system is responsible for filtering blood to form urine?
Answer:
Kidney
The kidneys filter approximately 120 to 150 quarts of blood daily to produce about 1 to 2 quarts of urine. They remove metabolic wastes, excess ions, and water while maintaining the body's acid-base and electrolyte balance.
95
What is the primary muscle responsible for the process of inhalation in the respiratory system?
Answer:
Diaphragm
The diaphragm is a dome-shaped sheet of muscle separating the thoracic and abdominal cavities. When it contracts, it flattens and moves downward, increasing the volume of the chest cavity and drawing air into the lungs.
96
Which heart chamber pumps oxygenated blood into the systemic circulation via the aorta?
Answer:
Left Ventricle
The left ventricle has the thickest muscular walls because it must generate enough pressure to pump oxygenated blood through the entire systemic circuit of the body, starting from the aorta.
97
In the digestive system, where does the majority of nutrient absorption occur?
Answer:
Small intestine
The small intestine is the primary site for the chemical digestion of food and the absorption of nutrients. Its large surface area, increased by structures like villi and microvilli, allows for efficient transfer of glucose, amino acids, and fatty acids into the bloodstream.
98
The 'Master Gland' of the endocrine system, which regulates other endocrine glands, is the:
Answer:
Pituitary gland
The pituitary gland is often called the master gland because it produces hormones that control the functions of many other endocrine glands, such as the thyroid, adrenals, and gonads. It is itself regulated by the hypothalamus.
99
Which layer of the skin contains blood vessels, nerves, and hair follicles?
Answer:
Dermis
The dermis is the thick layer of living tissue below the epidermis. It contains essential structures such as capillaries, sensory receptors, sweat glands, sebaceous glands, and hair follicles, providing structural support and nourishment to the skin.
100
What is the functional unit of the nervous system responsible for transmitting electrical signals?
Answer:
Neuron
The neuron is the basic structural and functional unit of the nervous system. It is specialized to receive, process, and transmit information through electrical and chemical signals across synapses, allowing for rapid communication throughout the body.