CONTROL AND COORDINATION

Q1 What is the difference between a reflex action and walking?

Difference between a reflex action and walking is as under:REFLEX ACTION WALKING

1. It is not under the control of will i.e., we cannot control by thinking about them.

2. Spinal cord controls reflex action.

1. It is under the control of will i.e., we can control by thinking about them.

2. Brain controls walking.

Q2 Which part of brain, maintains posture and equilibrium of the body?

Cerebellum of hindbrain maintains posture and equilibrium of the body.

Q3 What is the role of the brain in reflex action?

The mid-brain controls reflex movements (actions) of the head, neck and trunk. It also controls the reflex movements of the eye muscles, changes in pupil size and shape of the eye lens. The medulla oblongata of hindbrain controls heartbeat, breathing, blood pressure, sweating, coughing, sneezing, vomiting and salivation.

Q4 How is the shaple of the plant cells changed?

The shape of the plant cells changes by changing the amount of water in them, resulting in swelling or shrinking.

Q5 How does the pea plant climb up other plants or fences?

The pea plant climb up other plants or fences by means of tendrils

Q6 Are tendrils sensitive to touch?

Yes, tendrils are sensitive to touch.

Q7 What cause of the tendril to cling to object?

When the tendrils come in contact with any support, the part of tendril in contact with the object does grow as rapidly as the part of the tendril away from the object. Thus causes the tendril to circle around the object and thus cling to it.

Q8 What are external stimuli?

The factor that are external to the plant and bring about a response, are called external stimuli.

Q9 Define GEOTROPISM.Downward movement in response to gravitational force of the plant e.g., roots.

Q10 What are nastic movements?

In some plants the movement is neither towards nor away from the stimulus, e. g., the leaves of touch-me-not (Memosa pudica) plant bends or droops on touching.

Q11 Which other stimulus influences the roots other then gravity?

Water influences the roots other than gravity. Roots grow towards water.

Q12 Out of hydrotropism and GEOTROPISUM, WHICH stimulus is stronger in roots?

Hydrotropism

Q13 Which part of the plant shows phototropism?

Steam

Q14 What are the influences of light stimulus on roots?

Light stimulus has no influence on roots.

Q15 What is the main characteristic of touch-me-not plant?

On touching the leaves of the touch-me-not plant they close at once and after sometime the leaves spread out again.

Q16 Do plants have nervous or muscular system?

No.

Q17 Do plants respond to change in environment as ANIMALS? How can observe their response?

Yes, plants also respond to changes in environment. We can observe this through observing specific plant movements.

Q18 Give an example to show that plants respond to external stimuli.When we touch the leaves of touch-me-not plant, they fold up and drop. This shows that plants respond to external stimuli.

Q19 What are the two types of plant movements?

Two types of plant movements are:-1. Movements independent of growth.

2. Movement dependent on growth.Q20 Give example of a movement in plant that is independent of growth.

When we touch the leaves of chui-mui, the sensitive touch-me-not plant, the leaves bend and droop down. This movement is independent of growth.

Q21 In absence of nervous and muscular tissue, how the leaves of sensitive plant detect touch and move in response.

The plant detects the touch through electrical-chemical changes that is communicated from one cell to another. Plants do not have specialized tissue to conduct the information.

The response in terms of bending and drooping of leaves in the touch-me-not─ plant is because of change in shape of plant cells.

Plant cells change shape by changing the amount of water in them. Input of─ water results in swelling where as water loss causes shrinking.

Q23 What are the difference between the process of responding to stimulus in case of plants and animals?

PARAMETER IN PLANTS IN ANIMALSPresence of specialized tissue for conduction of information

Not present Nervous tissues present

Mechanism of change of shape

Achieved through changing the water content of cells

Achieved through rearrangements of specialized proteins

Q24 Give examples of movement due to growth in plants1. Growth of seedling from seed during germination.2. Coiling of tendrils when they come in contact with other plants or fence

in climbers.3. Bending of stem towards light4. Growth of roots towards the gravitational pull.5. Growth of pollen tubes towards ovule.6. Movement of sunflower in response to day or light

Q25 What is the term given to the growth movements in plants?Tropic movement

Q26 Define tropic movements.

The movement of a plant towards or away form the direction of stimulus is known as tropism.

Q28 What are the characteristics of tropic movements?

1. Tropic movements are directional. This means that plants respond to stimuli slowly by growing in a particular direction.

2. Tropic movements are dependent on the stimulus. The stimulus can be light, gravity, touch or chemicals. Plants respond to these by either growing towards the stimulus (positive) or away from stimulus (negative).

3. Tropic movements are growth movements. In absence of stimulus the growth will stop.

4. Growth related tropic movements are comparatively slower than those that are independent of growth.

5.Q29 Name different type of tropic movements.

Different types of tropic movements in plants are:1. PHOTOTROPISM ─ movement in response light.2. CHEMOTROPISM ─ movement due to chemicals.3. GEOTROPISM ─ movement to response to gravitational force.4. HYDROTROPISM ─ movement in response to water content.

Q30 Give one example of phototropism, geotropism, chemotropism and hydrotropism.

1. PHOTOTROPISM ─── When a growing plant is exposed to unidirectional light it responds by bending towards the light.

2. GEOTROPISM ─── Roots of plants always grow towards gravitational force.

3. CHEMOTROPISM ─── Growth of pollen tube towards ovule.4. HYDROTROPISM ─── Movements of roots towards water.

All types of tropic movements are directional. They can be towards the stimulus (positive) or away form it (negative). For example, shoots are positively phototropic (grow towards light) but roots are negatively phototropic (grow away from light). Similarly, shoots are negatively geotropic but roots are positively geotropic.

Q31 How do plants respond to external stimuli?

Plants lack nervous and muscular tissues. In the absence of these tissues, the stimulus cannot be communicated in the form of electrical impulse. Therefore, plants use electrical means of communication. In plants, the stimulated cells release a chemical compound (plant hormone) that would diffuse all around the cell. The other cell recognizes this chemical and responds accordingly.

Q32 What are the plant Hormones? Give example.Chemical substance that performs the function of control and coordination in plants are known as plant hormones. For e.g., auxin is a plant hormone.

Q33 Name various plant hormones.

Auxins, Gibberellin, Cytokinin, Abscisic acid and Ethylene.

Q34 Give the functions of various plant hormones.

1. AUXINS ─── It is synthesized at the shoot tip region and helps in the growth of cells. Auxin is sensitive to light. It moves in the direction away from light.2. GIBBERELLINS ─── Help in growth of stem in the internodes regions.3. CYTOKININS ─── It promotes cell division and is present in areas where rapid growth takes place like fruits and seeds.4. ABSCISIS ACID ── The hormone acts as growth inhibitor. Action of this hormone stops growth. For e.g., wilting and falling of leaf is controlled by abscisis acid.5. ETHYLENE ── Helps in ripening of fruits.

Q35 Explain the mechanism of action of auxin during phototropic response.

Phototropism is growth movement in plants in response to light. The shoot of the plants bend towards light where as root bends away from light. This phenomenon is controlled by plant hormone auxin. The mechanism of action of auxin during phototropism is as follow:──── Auxin is synthesized at the shoot tip. It helps the cells to grow longer.──── Auxin shows a characteristic feature of moving from side exposed to light towards shady side of plant.──── This results in uneven growth of plant cells at the tip region. Cells in shady side grows longer and faster than those in exposed side. Thus, the shoot bends towards light.

Q36 What are hormones?

Hormones are chemical substances secreted in trace amounts by specialized tissues, called endocrine glands. They help in control and coordination of various body parts and their functions.

Q37 What are endocrine glands?

Endocrine glands are body parts having specialized glandular tissues, which secrete chemical called hormones. These hormones help in regulating various body functions.

Q38 Why endocrine glands are called ductless glands?

Endocrine glands are also called ductless glands because they do not have ducts and their secretion the hormones, are poured directly into the blood.

Q40 What are the characteristics of hormones?

Characteristics of hormones are:(i) They are specific chemical messengers.(ii) They are secreted by endocrine glands.

(iii) They are poured directly into the blood and carried by blood circulation.

(iv) They act on specific tissue/organ called target organs.(v) They are secreted in very small amounts and only when

required by the body.

Q41 Name the endocrine glands of human body.

Some endocrine glands of our body are Pituitary (hypothesis), Pineal, Thyroid, Parathyroid, Pancreas, Adrenal, Testes, and Ovary.

Q42 Tabulates the functions of hormones secreted by various endocrine glands

in the human body.

HORMONES SECRETED

FUNCTIONS

1. Relasing Hormones

Regulates secretes of hormones from Pituitary.

2. Growth Hormones

Development of muscles and bones.

3. Tropic hormones

Regulate the hormones secretion of some endocrine glands like thyroid, adrenal, testes, ovaries etc.

4. Prolactin Regulation and functioning of mammary glands.5. Vasopressin Osmoregulation: regulation of water and electrolyte

balance in body.6. Oxytocin 1.Contraction of smooth muscles during child birth

2.Lactation7. Thyroxin Regulation of carbohydrate, fat and protein

metabolism.8. Parathyriod hormones

Regulation of blood calcium and phosphate levels.

9. Insulin Lowering blood glucose10.Glucagon Increase of blood glucose11.Adrenalin & corticoids

Regulation of ── Blood pressure.── Heart rate── Carbohydrate metabolism and mineral balance

12.Testosterone Regulation of ── Male accessory sex organs.── Secondary sexual characters in males like moustache, beard, change in voice, etc.

13.Estrogen Regulation of── Female accessory sex organs── Secondary sexual characters in females like growth of mammary glands, heir pattern, etc.

14.Progesterone Maintenance of pregnancy.

Q43 What is neuron?

Neuron is the largest cell in the body. It is an elongated branched cell having 3 components cell body, dendrites and axon, neuron are therefore, the structural and functional unit of nervous system.

Q44 Phytohormones (PLANT HORMONES) : are chemical substances naturally occurring in plant parts which bring about control and coordination in various plant activities, such as growth, development and response to environment.

Q45 What is a synapse.

The functional junction b/w the nerve endings of an axon of a neuron and dendrits of the next neuron are called a synapse.

Q46 Write the function of hormone ‘thyroxine’ in our bodies?

Because it stimulates the contraction of the smooth muscles of uterus at the end of pregnancy and helps in child birth.

Q47 Which endocrine gland performed the dual function of production of enzymes as well as hormones? Pancreas.

Q48 What happens at the synapse between two neurons?At the synapse two neurons join together.

Q49 How do we detect the smell of an agarbatti?

The olfactory receptors are present in the lining of the nose. These receptors send the information of the incense to the brain through a cranial sensory neuron where olfactory lobes of forebrain analyse and produce the sensation of smell.

Q50 Which signal we get disrupted in case of spinal cord injury?

An injury to the spinal cords will cause loss of all sensation, loss of reflex action, causing paralysis and degeneration of muscles.

Q51 Name the hormones secreted by the thyroid gland the pituitary gland and the pancreas, mention their function.

I Thyroid gland produces thyroxines. It regulates the metabolism of carbohydrates, fats and proteins and provide balance for growth.

II Pituitary gland produces the growth hormones. It regulates growth and development of the body. If there is deficiency of this hormone in the childhood as dwarfism. If the hormone is produced in excess in childhood, it causes gigantism and child will grow into a giant.

III PANCREAS Secrets insulin. Insulin maintains glucose level in the blood by changing excess glucose into glycogen, when it is not secreted in sufficient amount, the person suffers from diabetes.

Q52 Mention the different types of receptors found in human body and the sensation they perceive.

The different types of receptors are:I PHOTORECEPTORS : Perceive light e.g., eyes.II PHONORECEPTORS : perceive sound waves e.g., ears.III OLFACTORECEPTORS : Perceive sense of smell e.g., noseIV GUSTATORY RECEPTORS : Perceive sense of taste e.g., tongue.V SKIN : Sense of hotness, coldness, touch,

Q53 Explain reflex actions?

Reflex action is defined as an unconscious, automatic and involuntary response of effectors i.e., muscles and glands, to a stimulus. Which is monitored through the spinal cord?

Q54 What is difference between reflex action and walking?

A reflex action is an automatic response to a stimulus which is not under the conscious control while walking is a voluntary action which is controlled by brain.

Q55 How is movement of leaves of the sensitive plant different from a movement of a short towards light.

The movement of the leaves of the sensitive plant is neither towards nor away form stimulus like touch (mastic movement) while movements of short is towards stimulus like light. The movement of leaves of sensitive plants is not directional while the movement of short is directional.

Q56 How do auxins promote the growth of a tendril around a support?

Tendril of a plant like pea is sensitive to touch, when it comes in contact with support, the side of the tendril touching the support does not show growth, as auxin do not move into this region. But the side of the tendril which is not in contact with he support grows due to the effect of the auxin’s. Due to access growth on this side, the tendrils circle the support and climbs up.

Q57 Why is the use of iodized salt advisable?

Because iodine is necessary for the thyroid gland to produce thyroxin hormone. Thyroxin regulates carboxy protein and fat metabolism in which is required for growth. Deficiency of iodine in the body causes disorder like swollen neck and disease called goiter.

Q58 How does our body response when adrenaline is secreted in the blood?

It prepare a person to meet the emergency conditions by increasing heart beat, respiratory rate and access supply of blood to the skeletal muscles.

Q59 Why are some patients of diabetes treated by giving injections of insulin?

Insulin hormone is secreted by pancreas. This hormone helps in regulating sugar level in the blood. Its deficiency results in high sugar level in the blood and causes many harmful effects.

Q60 How does phototropism occur in plants?

The directional or tropic movement towards the light or away from the light is called phototropism. The short respond by bending away from the light.

Q61 What is the need for a system of control and coordination in an organism?

The different organs of our body work in co-ordination. When we perform any activity, for example when we are taking food, our eyes help in locating the food, our nose to our mouth, our hands brings the food to our mouth and saliva status the digestive process, So control and coordination is essential in maintaining a state of stability and a steady state between the internal conditions of an organism and the external events.

Q62 How are involuntary actions and reflex actions different from each other?

Reflex actions are not controlled by brain. They are controlled by spinal cord. Involuntary actions are controlled by midbrain and hind brain. Speed of response is slowing in involuntary but speed of response is very fast in reflex actions.

1. Experience Of reflex action ▬ removing hand from hot object.2. Experience of involuntary actions ▬ blood pressure, Salivation.

Q63 Why pituitary gland is called master gland?

Pituitary gland controls a numbers of functions of the body and secrets about nine hormones. It also controls activity of other endocrine glands, so it is called master gland.

Q64 What is a nerve impulse?

Information in the form of an electrochemical impulse which passes through neurons is known as nerve impulse.

Q65 What is a motor nerve?

A nerve which carries information from the CNS to the effectors organ is called motor nerve.

VERY SHORT QUESTION

Q1 What is endocrine gland?Q2 Name the five endocrine glands found in human body.Q3 Name the one female hormone.Q4 What are hormones?Q5 What is hydrotropism?Q6 Which fluid is present between cranium and nerves?Q7 Which part of brain contains cerebrum?Q8 Which is the highest coordinating centre of body?Q9 Which part of brain controls birthing movements?Q10 Where is electric impulse converted to chemical impulse?Q11 Into how many parts is the brain divided?Q12 How do plants respond to a stimulus through they don’t passes a nerves system.Q13 Give an example of a hormone which promotes growth in human beings.Q14 Which hormone in animals helps in emergency?Q15 Which glands produce adrenaline?Q16 Which plants hormones inhibits growth?Q17 Where are auxins produced in the plants?Q18 Which parts of brain (Nervous system) are involved in following activities?

(I) Balancing of the body posture(II) Salivation and vomiting (m. ob) (III) Reflex action (IV) Thinking

Q19 Which hormone is known as birth hormone?Q20 Where are adrenal glands situated/Q21 What is cranium?Q22 What are meninges?Q23 Name the type of coordination in plant and animals?Q24 Write parts of neuron?Q25 Are tendrils sensitive to touch?Q26 Define tropism ▬ the movement of plants in the direction of a stimulus is called

tropism?Q27 Why endocrine glands are are called ductless glands?Q28 Who gave the term hormone?Q29 Bay liss and starling?Q30 What are the dual glands? Give the two examples.Q31 How do hormones reach to different parts of the body?Q32 What are parts of force brain?Q33 Write name of three hormones secreted by pituitary glands.