Biology

Control and Coordination

Question:

What is the general name of chemical substances which bring about control and coordination in plants ?

Answer:

Phytohormones.

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Control and Coordination

Q 1.

Name, the disease caused by the deficiency of thyroxine hormone in the body.

Q 2.

If sugar is detected in the urine of a person, name the disease he is suffering from.

Q 3.

Mention the names of various phytohormones.

Q 4.

Which part of the brain maintains posture and balance of the body ?

Q 5.

Give an example of a plant hormone that promotes its growth. Where it is synthesized ?

Q 6.

Which gland secretes the growth hormone ?

Q 7.

Why is the response of a plant to a stimulus not observed immediately?

Q 8.

What makes a stem bend towards sunlight?

Q 9.

(a) Explain any three directional movements in plants.
(b) How brain and spinal cord are protected in human ?
(c) Name the master gland present in the brain.

Q 10.

Mention the function of adrenaline hormone.

Q 11.

(a) Define geotropism. Give one example of geotropism.
(b) What is meant by ‘positive geotropism’ and ‘negative geotropism ? Give one example of each type. Draw a labelled diagram to illustrate your answer indicating the plant part which shows positive geotropism and the plant part which shows negative geotropism.
(c) Name one plant part which exhibits positive thigmotropism.

Q 12.

Which one term in each of the following includes the other three ?
(a) thyroid, ductless gland, thymus, pituitary, ovary
(b) adrenalin, insulin, hormone, thyroxine, estrogen

Q 13.

(a) The human brain can be broadly divided into three regions. Name these three regions.
(b) What is cranium ? What is its function ?

Q 14.

What does CNS stand for ? Which part of CNS : (a) consists of two cerebral hemispheres, and (b) has spinal nerves attached to it ?

Q 15.

What is a neuron?

Q 16.

Name any two types of tropism.

Q 17.

Write the functions of any one part of the hind – brain.

Q 18.

Define reflex action with suitable examples.

Q 19.

What are meanings? What are their functions? Name the fluid, which is filled in between meanings.

Q 20.

Name any growth inhibiting phytohormone.

Q 21.

Why is it advised to use iodised salt in our diet ?

Q 22.

(a) How is brain protected from injury and shock?
(b) Name two main parts of hind brain and state the functions of each.

Q 23.

What is chemotropism? Give one example. Name any two plant hormones and mention their functions.

Q 24.

What are 'hormones'? State one function of each of the following hormones:
(i) Thyroxine (ii) Insulin

Q 25.

A potted plant is made to lie horizontally on the ground. Which part of the plant will show
(i) positive geotropism?
(ii) negative geotropism?

Q 26.

Name and explain the function of the hormone secreted by the pituitary gland in humans.

Q 27.

What is a reflex action? Describe the steps involved in a reflex action.

Q 28.

Which one of the following actions on touch is an example of chemical control?
(i) Movement on the touch-sensitive plant.
(ii) Movement in human leg.

Q 29.

(a) Name the two main constituents of the Central Nervous System in human beings.
(b) What is the need for a system of control and coordination in human beings?

Q 30.

Which plant hormone is responsible for the wilting and falling of leaves ?

Q 31.

Name the type of chemical substances that control the growth in plants.

Q 32.

Give one example each of a plant part:
(a) which is positively hydrotropic as well as positively geotropic.
(b) which is positively phototropic but negatively geotropic.

Q 33.

Which of the following is a growth movement and which is not ?
(a) folding up of leaves of sensitive plant on touching with hand.
(b) folding up of petals of dandelion flower when light fades.

Q 34.

Name the plant part :
(a) which bends in the direction of gravity but away from light
(b) which bends towards light but away from the force of gravity

Q 35.

What is a plant hormone ? Name four plant hormones. State one function of each.

Q 36.

(a) What is meant by ‘tropisms’ (or tropic movements) ? Explain with an example.
(b) What are the different types of tropisms ? Define each type of tropism. Write the name of stimulus in each case.
(c) How do tropisms differ from nasties (or nastic movements) ?

Q 37.

a) What are the short fibres of a neuron known as ?
What is the long fibre of a neuron known as ?

Q 38.

Give three examples of reflex actions.

Q 39.

State whether coughing is a voluntary action or reflex action.

Q 40.

(a) How does chemical coordination take place in human beings ?
(b) Why is the use of iodised salt advisable ?

Q 41.

What is the function of insulin hormone ? What type of patients are given insulin injections ?

Q 42.

(a) What is a reflex action ? Explain with the help of an example.
(b) Define reflex arc. Give the flow chart of a spinal reflex arc.
(c) How are involuntary actions and reflex actions different from each other ?

Q 43.

(a) Name two systems which taken together perform the functions of control and coordination in human beings.
(b) What does the central nervous system in humans consist of ? What is the job of the central nervous system ?
(c) Give the various functions of brain.

Q 44.

Answer the following:
(a) Name the endocrine gland associated with brain?
(b) Which gland secretes digestive enzymes as well as hormones?
(c) Name the endocrine gland associated with kidneys?
(d) Which endocrine gland is present in males but not in females?

Q 45.

How does control and coordination takes place in plants?

Q 46.

What is the autonomic nervous system?

Q 47.

List the functions of testosterone and estrogen.

Q 48.

Write name of three hormones secreted by the pituitary gland.

Q 49.

What is coordination?

Q 50.

What are phytohormones?