Name various plant hormones. Also give their physiological effects on plant growth and development.
The various plant hormones are Auxin, Gibberellin,Cytokinin, and Abscisic acid. Their physiological effects on plant growth are as follows:
Auxins: Cell elongation, cell division, root formation, apical dominance, inhibition of abscission and fruit growth.
Gibberellins: Growth in stem and leaves, higher fruit yield and over coming dormancy.
Cytokines: Promotes cell division, differentiation, prevention of senescence and overcoming apical dominance .
Absciscic acid: Induces dormancy, senescence, abscission, checking excessive activity of growth promoting hormone and closure of stomata under water stress.
(a) Name the hormones secreted by the following endocrine glands :
(i) Thyroid gland (ii) Parathyroid glands (iii) Pancreas (iv) Adrenal glands
(b) Write the functions of testosterone and oestrogen hormones.
(a) What does a plant root do in response to water ? What is this phenomenon known as ?
(b) What happens to the moonflower (i) during daytime, and (ii) at night ? What is this phenomenon known as ?
What is the function of insulin hormone ? What type of patients are given insulin injections ?
(a) Which plant hormone is present in greater concentration in the areas of rapid cell division?
(b) Give one example of a plant growth promoter and a plant growth inhibitor.
a) What are the short fibres of a neuron known as ?
What is the long fibre of a neuron known as ?
Which halogen element is necessary for the making of thyroxine hormone by the thyroid gland ?
(a) Name the structural and functional unit of nervous system.
(b) Draw a flow chart to show the classification of nervous system into various parts.
(c) What is autonomic nervous system ? What is its function ?
(d) What is voluntary nervous system ? Explain the working of voluntary nervous system with an example.
(a) What does a stem (or shoot) do in response to gravity ? What is this phenomenon known as ?
(b) What does a root do in response to light ? What is this phenomenon known as ?
State the functions of the following hormones :
(a) Thyroxine (b) Adrenaline (c) Growth hormone
Give the scientific terms used to represent the following :
(a) Bending of a shoot towards light.
(b) Growing of roots towards the earth.
(c) Growth of a pollen tube towards ovule.
(d) Bending of roots towards water.
(e) Winding of tendril around a support
Give one example of the movement of a plant part which is caused by the loss of water (or migration of water).
(a) What does a Mimosa pudica plant do in response to touch ? What is this phenomenon known as ?
(b) What happens to the dandelion flower (z) during daytime, and (ii) at night ? What is this phenomenon known as ?
(a) The human brain can be broadly divided into three regions. Name these three regions.
(b) What is cranium ? What is its function ?
What is chemotropism? Give one example. Name any two plant hormones and mention their functions.
Name, the two main organs of our central nervous system. Which one of them plays a major role in sending command to muscles to act without involving thinking process? Name the phenomenon involved.
Name the plant hormones which help/promote (i) cell division (ii) growth of
the stem and roots?
Distinguish between tropic movements and nastic movements in plants. Give examples to illustrate your answer.
Name one gland each :
(a) which acts only as an endocrine gland.
(b) which acts only as an exocrine gland.
(c) which acts both as an endocrine gland as well as an gxocrine gland.
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
In what ways are puberty and adolescence result of the activity of some glands in the human body ?
(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 ?
What causes a tendril to encircle or coil around the object in contact with it is? Explain the process involved.
Name and explain the function of the hormone secreted by the pituitary gland in humans.
What is the general name of chemical substances which bring about control and coordination in plants ?
Name one example of the movement of a plant part which is very quick and can be observed easily.