All Free Biology MCQs with Answers
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19,844 questions · page 934 of 993
- A. Amylase
- B. Apoenzyme
- C. Holoenzyme
- D. Coenzyme
Explanation: Option A is incorrect because Amylase is the enzyme that breakdown carbohydrates.Option B is incorrect because Apoenzyme is the enzyme…
Correct answer: Holoenzyme18662. If the cofactor is covalently or tightly and permanently bonded to enzyme then it will be called:
- A. Coenzyme
- B. Prosthetic group
- C. Activator
- D. Apoenzyme
Explanation: The detachable cofactor is known as an activator if it is an inorganic ion.
Correct answer: Prosthetic group18663. Some enzymes require helper which is non-protein part for its efficient functioning that is called:
- A. Accelerator
- B. Cofactor
- C. Prosthetic group
- D. Apoenzyme
Explanation: Some enzymes require non protein parts for their proper functioning. If the non-protein part is covalently bonded, it is known as a…
Correct answer: Cofactor- A. Prosthetic group
- B. Activator
- C. Co-enzyme
- D. Inhibitor
Explanation: Mg2+ is an essential inorganic activator for enzyme phosphatase, not to be confused with the prosthetic group.
Correct answer: Activator- A. Coenzymes
- B. Activators
- C. Prosthetic group
- D. Apoenzyme
Explanation: Activators are inorganic ions that bind to enzymes and play a crucial role in enzyme activity.
Correct answer: Activators- A. TSH
- B. ACTH
- C. ADH
- D. STH
Explanation: Somatotrophin hormone (STH) continues to promote protein synthesis throughout the body even after adolescence.
Correct answer: STH- A. STH and LH
- B. FSH and STH
- C. ACTH and LH
- D. FSH and LH
Explanation: Explanation:FSH and LH are both gonadotropins that are involved in the regulation of reproductive function.
Correct answer: FSH and LH- A. Glycerol
- B. Sterol
- C. Amino acids
- D. Cholesterol
Explanation: Option[A] Lipids are made from glycerolOption[b] Sterols are sub groups of steroidsOption[c] Amino acid is the basic unit of protein.
Correct answer: Cholesterol- A. They initiate new biochemical reactions
- B. They are poured directly into blood
- C. They may be proteins
- D. They affect target cells
Explanation: Option [A] Hormones do not start a new biochemical reaction itself instead whenever a stimulus hormone is released in blood and reaches…
Correct answer: They initiate new biochemical reactions- A. Aldosterone
- B. Epinephrine
- C. Androgen
- D. Corticosterone
Explanation: The adrenal medulla produces catecholamines, epinephrine, and norepinephrine.
Correct answer: Epinephrine- A. Adrenaline, Aldosterone
- B. Epinephrine, Nor-epinephrine
- C. Cortisone, Oxytocin
- D. Thyroxine, Nor-epinephrine
Explanation: Epinephrine and norepinephrine stimulate the effects of the sympathetic system (fight or flight).
Correct answer: Epinephrine, Nor-epinephrine- A. Renin
- B. Aldosterone
- C. Angiotensin
- D. CPK
Explanation: Aldosterone (ALD) is a hormone that helps regulate your blood pressure by managing the levels of sodium (salt) and potassium in your blood…
Correct answer: Aldosterone- A. Renin
- B. Antidiuretic hormone
- C. Angiotensin
- D. Growth Factor
Explanation: The antidiuretic hormone, also known as vasopressin, is produced in the hypothalamus and stored in the posterior pituitary gland.
Correct answer: Antidiuretic hormone- A. FSH
- B. MSH
- C. Melatonin
- D. Prolactin
Explanation: Melatonin is a hormone secreted by the pineal gland that helps regulate our diurnal (daily) rhythms, including sleep-wake cycles.
Correct answer: Melatonin- A. Iodine metabolism
- B. Protein metabolism
- C. Glucose metabolism
- D. Basal metabolic rate
Explanation: Thyroxine hormone stimulates various metabolic activities such as the metabolism of glucose, cholesterol metabolism etc leading to an…
Correct answer: Basal metabolic rate- A. TSH
- B. STH
- C. ACTH
- D. Gonadotropin hormone
Explanation: Somatotrophic hormone (STH), also known as growth hormone (GH), is the only hormone released by the anterior pituitary that is not…
Correct answer: STH- A. Liver
- B. Adrenals
- C. Thyroid
- D. Pancreas
Explanation: The pancreas has the dual function of secreting glucagon and insulin into blood (endocrine) and secreting enzymes in the form of the…
Correct answer: Pancreas- A. Autosome 9.
- B. Autosome 7.
- C. Autosome 1.
- D. Autosome 3.
Explanation: b) Autosome 7: This is the correct option. The genes for blue opsin (a type of photoreceptor in the eye) are located on chromosome 7…
Correct answer: Autosome 7.- A. Klinefelter's Syndrome
- B. Down's Syndrome
- C. Jacob's Syndrome
- D. Edward's Syndrome
Explanation: Explanation:XXY chromosomes in a male cause Klinefelter's syndrome.This option is not correct.
Correct answer: Klinefelter's Syndrome- A. XO
- B. XXY
- C. XYY
- D. XXX
Explanation: [A] XO chromosomal abnormality results in Turner syndrome which does not causes aggression and antisocial behaviour[B] XXY,Klinefelter…
Correct answer: XYY