(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.
(a) Nervous system and endocrine system.
(b) The central nervous system consists of the brain and spinal cord. The work of the CNS is to direct incoming messages to the motor neurons that are connected to the part of the body which will respond to a stimulus. It is involved in complicated responses where both (brain and spinal cord) work. It enables a person to give a more appropriate and more intelligent response to various situations.
(c)
(i) The brain receives information carrying nerve impulses from all the sensory organs of the body.
(ii) It responds to the impulses brought in by sensory organs by sending its own instructions through motor nerves to the muscles and glands causing them to function accordingly.
(iii) It correlates the various stimuli from different sense organs and produces the most appropriate and intelligent response.
(iv) It coordinates the body activities so that the mechanisms and chemical reactions of the body work together efficiently.
(v) It stores information so that behavior can be modified according to the past experience.
What is the function of insulin hormone ? What type of patients are given insulin injections ?
(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 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 ?
(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.
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
(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 ?
Which halogen element is necessary for the making of thyroxine hormone by the thyroid gland ?
State the functions of the following hormones :
(a) Thyroxine (b) Adrenaline (c) Growth hormone
Name the plant hormones which help/promote (i) cell division (ii) growth of
the stem and roots?
What is the general name of chemical substances which bring about control and coordination in plants ?
a) What are the short fibres of a neuron known as ?
What is the long fibre of a neuron known as ?
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
(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 ?
Mention one function for each of these hormones:
(a) Thyroxin (b) Insulin (c) Adrenaline (d) Growth hormone (e) Testosterone.
Name various plant hormones. Also give their physiological effects on plant growth and development.
Write one example each of the following tropic movements :
(i) Positive phototropism (ii) Negative phototropism
(iii) Positive geotropism (iv) Negative geotropism
(v) Hydrotropism (vi) Chemotropism
What causes a tendril to encircle or coil around the object in contact with it is? Explain the process involved.
State the functions of any three of the structural and functional unit of nervous system.
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 and explain the function of the hormone secreted by the pituitary gland in humans.
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 ?
What is a tendril ? Name the two types of tendrils. What does a tendril do in response to the touch of a support ? 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 ?
Compare the nervous system and endocrine system (hormonal system) for control and coordination in humans.
Explain the difference between each of the following pairs of terms :
(a) receptor and effector (b) cerebrum and cerebellum
Why is the flow of signals in a synapse from axonal end of one neuron to dendritic end of another neuron but not the reverse?