What is the type of reaction that involves the loss of electrons by a species?
A. Oxidation reaction
B. Reduction reaction
C. Acid-base reaction
D. Neutralization reaction
Correct Answer: A An oxidation reaction is a type of reaction that involves the loss of electrons by a species.
Q2. Biology
Which hormone is called the "fight or flight" hormone?
A. Insulin
B. Adrenaline
C. Thyroxine
D. Estrogen
Correct Answer: B Adrenaline (epinephrine) prepares body for stress (increases HR, BP, etc.).
Q3. Physics
What is the nature of the force between two parallel current-carrying conductors?
A. Repulsive
B. Attractive
C. Both attractive and repulsive
D. Neutral
Correct Answer: C The force between two parallel current-carrying conductors can be either attractive or repulsive, depending on the direction of the current flow.
Q4. Physics
The coefficient of performance of a refrigerator is given by:
A. Q/W
B. Q/W
C. W/Q
D. (Q-Q)/W
Correct Answer: B COP = Q/W where Q is heat extracted from cold reservoir and W is work input.
Q5. Biology
Blood group with no antigens on RBC is:
A. A
B. B
C. AB
D. O
Correct Answer: D Blood group O has no A or B antigens on RBCs but has both anti-A and anti-B antibodies.
Q6. Biology
A person suffers from abnormally high blood glucose levels, frequent urination, and excessive thirst. Which of the following conditions is most likely causing these symptoms?
A. Diabetes insipidus
B. Hypothyroidism
C. Diabetes mellitus
D. Addison's disease
Correct Answer: C The symptoms described are classic indicators of Diabetes Mellitus.
* **High blood glucose levels (hyperglycemia):** This is the hallmark of diabetes mellitus, caused by insufficient insulin production or insulin resistance, leading to glucose accumulation in the blood.
* **Frequent urination (polyuria):** High glucose levels in the blood lead to glucose excretion in the urine, drawing water with it due to osmosis, resulting in increased urine output.
* **Excessive thirst (polydipsia):** The loss of fluids through frequent urination leads to dehydration, triggering a sensation of intense thirst.
Let's look at the other options:
* **Diabetes insipidus:** Characterized by frequent urination and thirst, but it is due to a deficiency of ADH (vasopressin) or kidney's inability to respond to ADH, and does not involve high blood glucose levels.
* **Hypothyroidism:** Caused by low thyroid hormone levels, leading to symptoms like weight gain, fatigue, cold intolerance, and slow metabolism, not primarily high blood glucose.
* **Addison's disease:** Results from adrenal insufficiency, affecting cortisol and aldosterone production, leading to symptoms like fatigue, weight loss, low blood pressure, and skin hyperpigmentation, not typically high blood glucose.
Q7. Biology
Which organelle is involved in protein synthesis?
A. Mitochondria
B. Ribosome
C. Lysosome
D. Golgi body
Correct Answer: B Ribosomes (composed of rRNA + proteins) synthesize proteins.
A solid cylinder of mass M and radius R rolls without slipping on a horizontal surface with a linear velocity v. The kinetic energy of the cylinder is:
A. (1/2)Mv^2
B. (3/4)Mv^2
C. Mv^2
D. (1/4)Mv^2
Correct Answer: B The total kinetic energy (KE_total) of a body rolling without slipping is the sum of its translational kinetic energy (KE_translational) and rotational kinetic energy (KE_rotational).
KE_total = KE_translational + KE_rotational
KE_translational = (1/2)Mv^2
KE_rotational = (1/2)I^2
For a solid cylinder, the moment of inertia I = (1/2)MR^2.
For rolling without slipping, the linear velocity v and angular velocity are related by v = R, so = v/R.
Substituting these into the rotational kinetic energy equation:
KE_rotational = (1/2) * ((1/2)MR^2) * (v/R)^2
KE_rotational = (1/4)MR^2 * (v^2/R^2)
KE_rotational = (1/4)Mv^2
Now, sum the translational and rotational kinetic energies:
KE_total = (1/2)Mv^2 + (1/4)Mv^2
KE_total = (2/4)Mv^2 + (1/4)Mv^2
KE_total = (3/4)Mv^2
Q10. Chemistry
What is the type of isomerism that occurs when molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional arrangement of their atoms?
A. Structural isomerism
B. Stereoisomerism
C. Enantiomerism
D. Tautomerism
Correct Answer: B Stereoisomerism occurs when molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional arrangement of their atoms.
Q11. Physics
A body of mass 5 kg is moving with momentum 20 kg m/s. Its velocity is:
A. 2 m/s
B. 4 m/s
C. 100 m/s
D. 0.25 m/s
Correct Answer: B v = p/m = 20/5 = 4 m/s.
Q12. Biology
The respiratory pigment in human blood is:
A. Chlorophyll
B. Hemoglobin
C. Melanin
D. Myoglobin
Correct Answer: B Hemoglobin in RBCs transports O from lungs to tissues.
Q13. Biology
Which part of the brain controls balance and coordination?
A. Cerebrum
B. Cerebellum
C. Medulla
D. Hypothalamus
Correct Answer: B Cerebellum coordinates voluntary movements, balance, and posture.
Q14. Biology
Which of the following hormones is secreted by the anterior pituitary gland?
A. Antidiuretic hormone (ADH)
B. Oxytocin
C. Growth hormone (GH)
D. Melatonin
Correct Answer: C The anterior pituitary gland secretes several hormones, including Growth Hormone (GH), Thyroid-Stimulating Hormone (TSH), Adrenocorticotropic Hormone (ACTH), Follicle-Stimulating Hormone (FSH), Luteinizing Hormone (LH), and Prolactin. ADH and Oxytocin are secreted by the posterior pituitary, and Melatonin is secreted by the pineal gland.
Q15. Biology
Which part of the nephron is impermeable to water but permeable to salts, leading to the dilution of filtrate?
A. Proximal Convoluted Tubule (PCT)
B. Descending limb of Henle's loop
C. Ascending limb of Henle's loop
D. Distal Convoluted Tubule (DCT)
Correct Answer: C The ascending limb of Henle's loop is characterized by its impermeability to water. However, it actively reabsorbs sodium and chloride ions (and some other electrolytes) from the filtrate into the interstitial fluid. As solutes are removed from the filtrate but water is retained, the filtrate becomes progressively more dilute as it moves up the ascending limb.
- PCT: Permeable to both water and salts, involved in bulk reabsorption.
- Descending limb of Henle's loop: Highly permeable to water but largely impermeable to electrolytes, leading to concentration of filtrate.
- DCT: Involved in conditional reabsorption of water and sodium, not primarily responsible for initial dilution due to impermeability to water while being permeable to salts.