Tamil Nadu Board Samacheer Kalvi solutions for Class 10th SSLC Science Answers Guide chapter 16 - Plant and Animal Hormones [Latest edition]

Gibberellins cause: ______

The hormone which has a positive effect on apical dominance is: ______

Which one of the following hormones is naturally not found in plants: ______

Avena coleoptile test was conducted by ______

To increase the sugar production in sugarcanes they are sprayed with ______

LH is secreted by ______

Identify the exocrine gland.

Which organ acts as both an exocrine gland as well as an endocrine gland.

Which one is referred to as “Master Gland”?

______ causes cell elongation, apical dominance and prevents abscission.

______ is a gaseous hormone involved in the abscission of organs and acceleration of fruit ripening.

______ causes stomatal closure.

Gibberellins induce stem elongation in ______ plants.

The hormone which has a negative effect on apical dominance is ______.

Calcium metabolism of the body is controlled by ______.

In the islets of Langerhans, beta cells secrete ______.

The growth and functions of the thyroid gland are controlled by ______.

Decreased secretion of thyroid hormones in children leads to ______.

Match Column I with Columns II and III.

Match the following hormones with their deficiency states.

A plant hormone concerned with the stimulation of cell division and promotion of nutrient mobilization is cytokinin.

Gibberellins cause parthenocarpy in tomatoes.

Ethylene retards the senescence of leaves, flowers, and fruits.

Exophthalmic goiter is due to the over secretion of thyroxine.

The pituitary gland is divided into four lobes.

Estrogen is secreted by the corpus luteum.

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of Reason (R) is given just below it. Mark the correct statement as.

• Assertion: The application of cytokinin to marketed vegetables can keep them fresh for several days.
• Reason: Cytokinins delay the senescence of leaves and other organs by mobilization of nutrients.

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of Reason (R) is given just below it. Mark the correct statement as.

• Assertion (A): The pituitary gland is referred to as the “Master gland”.
• Reason (R): It controls the functioning of other endocrine glands.

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of Reason (R) is given just below it. Mark the correct statement as.

• Assertion (A): Diabetes mellitus increases blood sugar levels.
• Reason (R): Insulin decreases blood sugar levels.

Which hormone promotes the production of male flowers in Cucurbits?

Write the name of synthetic auxin.

Which hormone induces parthenocarpy in tomatoes?

What is the hormone responsible for the secretion of milk in females after childbirth?

Name the hormones which regulate water and mineral metabolism in man.

Which hormone is secreted during an emergency situation in a man?

Which gland secretes digestive enzymes and hormones?

Name the endocrine glands associated with kidneys.

What are synthetic auxins? Give examples.

What is bolting? How can it be induced artificially?

Bring out any two physiological activities of abscisic acid?

What will you do to prevent leaf fall and fruit drop in plants? Support your answer with reason.

What are chemical messengers?

Write the differences between the endocrine and exocrine glands. 

What is the role of parathormone?

What are the hormones secreted by the posterior lobe of the pituitary gland? Mention the tissues on which they exert their effect.

Why are thyroid hormones referred to as personality hormones?

Which hormone requires iodine for its formation?

What will happen if the intake of iodine in our diet is low?

Name the gaseous plant hormone. Describe its three different actions in plants.

Which hormone is known as a stress hormone in plants? Why?

Describe an experiment that demonstrates that growth-stimulating hormone is produced at the tip of the coleoptile.

Write the physiological effects of gibberellins.

Where are estrogens produced?

What is the role of estrogens in the human body?

What are the conditions which occur due to lack of ADH and insulin? How are the conditions different from one another?

What would be expected to happen if Gibberellin is applied to rice seedlings?

What would be expected to happen if A rotten fruit gets mixed with unripe fruits?

What would be expected to happen if When cytokinin is not added to the culture medium.

A plant hormone was first discovered in Japan when rice plants were suffering from Bakanae disease caused by Gibberella fujikoroi. Based on this information answer the following question:

Identify the hormone involved in this process.

A plant hormone was first discovered in Japan when rice plants were suffering from Bakanae disease caused by Gibberella fujikoroi. Based on this information answer the following question:

Which property of this hormone causes the disease?

A plant hormone was first discovered in Japan when rice plants were suffering from Bakanae disease caused by Gibberella fujikoroi. Based on this information answer the following question:

Give two functions of this hormone.

Senthil has high blood pressure, protruded eyeball, and an increased body temperature. Name the endocrine gland involved and the hormone secretion responsible for this condition.

Sanjay is sitting in the exam hall. Before the start of the exam, he sweats a lot, with an increased rate of heartbeat. Why does this condition occur?

Susan’s father feels very tired and frequently urinates. After clinical diagnosis, he was advised to take an injection daily to maintain his blood glucose level. What would be the possible cause for this? Suggest preventive measures.