Tag: zoology

Quizzes (289) Questions (5869)

Questions Related to zoology

Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Function of pineal gland is to 

  1. Control sexual behaviour

  2. Regulate period of puberty

  3. Lighter skin colour

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Pineal gland is a small, stalked and rounded gland present on the dorsal side of forebrain. This gland secretes melatonin hormone which regulates many important functions in the body like circadian rhythm of the body, sleep-wake cycle, body temperature etc. It also regulates pigmentation and control sexual behaviour. Melatonin also influences menstrual cycle. In man, at the time of puberty, pineal gland starts to get calcified and the calcium deposits are known as brain sand. Thus, it also regulate puberty period.
So, the correct answer is 'All of the above'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Pineal gland secretes melatonin which is connected to

  1. Colouration of skin

  2. Sleep

  3. Anger

  4. Body temperature
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones. Melatonin is derived from amino acid tryptophan and secreted from pineal gland. It regulates the 24 hour rhythm of our body like sleep-wake cycle. Its levels in the body increase during night and fall in the morning time. High levels of melatonin induce sleep and hence, it regulates sleep-wake cycle of the body.
So, the correct answer is 'Sleep'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

With increasing age, secretion of which of the following is reduced to half?

  1. HGH

  2. Estrogen

  3. GTH

  4. Melatonin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Melatonin is secreted from pineal gland which is located at the dorsal side of forebrain. Melatonin hormone is derived from amino acid tyrosine. It regulates circadian rhythm of body like sleep-wake cycle, temperature of body etc. It also regulates pigmentation, metabolism and defence capability. With increasing age, secretion of melatonin is decreased and reduces to about half.
So, the correct answer is 'Melatonin'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Serotonin and melatonin are hormones secreted by 

  1. Pancreas

  2. Pineal body

  3. Pituitarygland

  4. Thymus
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. Pancreas has two types of cells in the islet of Langerhans called alpha cells and beta cells which produce glucagon and insulin respectively.
B. Pineal body secreted melatonin and serotonin.
C. Pituitary gland has two parts adenohypophysis and neurohypophysis. Adenohypophysis secretes growth hormone (GH), thyroid stimulating hormone (TSH), adrenocorticotrophic hormone (ACTH), melanocyte stimulating hormone (MSH), prolactin (PRL), follicle stimulating hormone(FSH)  and luteinizing hormone (LH). Neurohypophysis secretes vasopressin and oxytocin. 
D. Thymus secretes peptide hormones thymosins.
So, the correct answer is 'Pineal body'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Melatonin is produced from 

  1. Pineal gland

  2. Adrenal gland

  3. Parathyroid gland

  4. Ovary
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Pineal gland produces melatonin which regulate 24 hour (diurnal) rhythm of the body.
B. Adrenal gland produces adrenaline and noradrenaline by adrenal medulla and corticoids by adrenal cortex.
C. Parathyroid gland produces parathyroid hormone (PTH).
D. Ovary produces estrogen and progesterone.
So, the correct answer is 'Pineal gland'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

The pineal gland secretes a hormone progesterone which helps to regulate sleep pattern. Thyroid glands release hormone which regulate the level of calcium in the blood with the help of calcitonin which is produced in the parathyroid glands. Select the correct option regarding the given paragraph.
i) Positions of pineal and parathyroid should be interchanged
ii) Progesterone must be replaced by melatonin
iii) Parathyroid should not be replaced as it is correctly mentioned.
iv) Positions of progesterone and calcitonin should be interchanged
v) Positions of thyroid and parathyroid should be interchanged 

  1. ii and v only

  2. i, ii and v only

  3. i and iii only

  4. ii and iv only
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The correct statement is- 'The pineal gland secretes a hormone melatonin which helps to regulate sleep pattern. Parathyroid Gland release hormone which regulates the level of calcium in the blood with the help of calcitonin which is produced in the thyroid gland.'

So the correct option is 'ii and v only'.

Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

The function of pineal body is to.

  1. Lighten the skin colour

  2. Control sexual behaviour

  3. Regulate the period of puberty

  4. All of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Pineal body is a very small, reddish-grey, vascular, conical, solid body located in the brain. It secretes a hormone named melatonin. Melatonin concentrates pigment granules in the melanocytes, making the skin colour lighter in certain animals. It also regulates the functioning of gonads, thus, controls, sexual behaviour and regulates the period of puberty.

Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

A hormone responsible for normal sleep-wake cycle is?

  1. Epinephrine

  2. Gastrin

  3. Melatonin

  4. Insulin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Melatonin is a hormone secreted by pineal gland. Immediately above the optic chiasma(in the brain) in a nucleus, are present melatonin receptors that react to this hormone and synchronise the nucleus to the $24$hrs day/night rhythm, thus informing the brain when it is day and when it is night.