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Chemical co-ordination in plants are achieved by plant hormones, that help to coordinate growth, development and responses to the environment.

Addison’s disease is caused by the hyposecretion of ACTH that leads to adrenal failure.

(a) Bending of stem towards light.

(b) Folding up of leaves of a sensitive plant on touching.

Reflex actions are involuntary actions which occur unknowingly. Voluntary actions on the other hand are performed consciously. Picking up an apple and eating it is an example of voluntary action whereas withdrawal of hand on touching a hot object is an example of reflex action.

 The plant hormones which help or promote: 

(i) Cell division — Cytokinins 

(ii) Growth of the stem — Gibberellins

Gibberellins help in the growth of stem.

Auxin is the hormone which is usually synthesised in the young tip of roots and shoots. When light is coming from one side of the plant, it diffuses towards the shady side of the shoot which stimulates the cells to grow longer, resulting in the bending of shoot towards the light, thus auxin promotes phototropism.

Correct answer is (d) hypothalamus

Hypersecretion of corticoids causes Cushing’s disease.

Tendrils are the thin, thread-like growths on the stems or leaves of climbing plants. The two types of tendrils are stem tendrils and leaf tendrils. The tendrils grow towards the things they happen to touch. This phenomenon is known as thigmotropism.

Cytokinins hormone promote cell division.

Correct answer is (b) hypersecretion of corticoids

(a) Phototropism.

(b) Geotropism.

(c) Light.

(d) Gravity.

(e) Touch.

(f) Earth, gravity.

(g) Geotropism.

(h) Auxin.

(i) Photonasty

(a) Root bends downwards in the direction of gravity; positive geotropism. 

(b) Stem bends towards the light; positive phototropism.

Spinal cord is a part of the central nervous system that is housed inside the vertebral column. It is an extension of the brain and is responsible for reflex actions. Spinal cord receives impulses from the sense organs and controls body responses. 

The spinal cord is protected by vertebrae and meninges (protective membranes) around it. The cerebrospinal fluid fills the spaces between these meninges and acts as a cushion thereby protecting the spinal cord and also the brain.

Auxin is made at the tip of the plant stem.

Growth of pollen tubes towards omles.

Chemotropism is the movement of a part of the plant in response to a chemical stimulus. It can be positive chemotropism or negative chemotropism. Example: The growth of pollen tube towards a chemical which is produced by an ovule during the process of fertilisation in a flower. Two plant hormones with their functions are as follows: Auxins promote cell elongation, root formation, cell division, respiration and other physiological processes like protein synthesis, etc. 

Gibberellins stimulate stem elongation, seed germination and flowering.

Given statement is true. 

Explanation: Since here directional movement take place in pollen tubes due to presence of ovules. This is an example of chemotropism and is true.

(a) Stem grows upward against the direction of gravity; negative geotropism.

(b) Root bends away from light; negative phototropism

Correct answer is (a) Grave’s disease

Spinal cord is enclosed in a bony cage called vertebral column.

(a) Phototropism. 

(b) Geotropism. 

(c) Light. 

(d) Gravity. 

(e) Touch. 

(f) Earth, gravity. 

(g) Geotropism. 

(h) Auxin. 

(i) Photonasty.

Mimosa pudica.

Mimosa pudica.

(i) Root 

(ii) Shoot

• TV programming was introduced experimentally in India to promote rural development as early as 1959. Later, the Satellite Instructional Television Experiment (SITE) broadcasted directly to community viewers in the rural areas of 6 states between August 1975 and July 1976. 

• These instructional broadcasts were broadcasted to 2400 TV sets directiy for 4 hours daily. 

• In 1991, there was one state controlled TV channel Doordarshan in India. By 1998, there were almost 70 channels. Privately run satellite channels have multiplied rapidly since mid-1990s, while Doordarshan broadcasts over 20 channels there were some 40 private television networks broadcasting in 2000. The staggering growth of private satellite television has been one of the defining developments of contemporary India. 

• The Gulf War of 1991 (which popularized CNN), and the launching of star-TV in the same year by the Whampoa Hutchinson Group signalled the arrival of satellite channels in India. In 1992, Zee TV, a Hindi based satellite entertainment channel, also began beaming programs to cable TV viewers in India. By 2000, 40 private cable and satellite channels were available including several that focused exclusively on regional-language broadcasting like Sun-TV, Udaya-TV, Raj TV, and Asianet. 

• While Doordarshan was expanding rapidly in the 1980s, the cable television industry was mushrooming in major Indian cities. The VCR greatly multiplied entertainmentoptions for Indian audiences, providing alternatives to Doordarshan’s single channel programming. Video viewing at home and in community-based parlours increased rapidly. The video fare consisted mostly of film-based entertainment, both domestic begun wiring apartment buildings to transmit several films a day. The number of cable operators also increased significantly. 

• The coming in of transnational television companies like Star TV, MTV, Channel V, Sony and others, worried some people on the likely impact on Indian youth and on the Indian cultural identity. But most transnational television channels have through research realized that the use of the familiar is more effective in procuring the diverse groups that constitute Indian audience. The early strategy of Sony .International was to broadcast 10 Hindi films a week, gradually decreasing the number as the station produced its own Hindi language content. The majority of foreign networks have now introduced either a segment of Hindi language programming (MTV India) or an entire new Hindi language channel (Star Plus). Star Sports and ESPN have dual commentary or an audio soundtrack in Hindi. The larger players have launched specific regional channels in languages such as Bengali, Punjabi, Marathi and Gujarati. 

• Localisation of STAR TV- in October 1996, STAR Plus initially an all English general entertainment channel originating from Hong Kong, began producing a Hindi language belt of programming between 7 and 9 PM. By February 1999, the channel was converted to a solely Hindi channel and all English serials shifted to STAR World, the network’s English language international channel. Advertising to promote the Hindi channel included the Hindi slogan: ‘Aapki Boli, Aapka Plus Point). 

• Both STAR and Sony continued to dub US programming for younger audience as children appeared to be able to adjust to the peculiarities that arise when the language is one and the setting another.

(1) Goitre is the enlargement of thyroid gland. It is easily visible at the base of neck when a person is suffering from it.

(2) Goitre is of two types.

1. Simple goitre : It is also called endemic goitre. This is due to iodine deficiency in the food. This causes iodine deficit in blood. In an attempt to take more iodine from blood, the blood supply to the gland increases. This results in swelling on the thyroid. 

2. Exophthalmic goitre : It is also called toxic goitre. This is due to hyperactive thyroid gland. This can happen if there is overstimulation of thyroid due to excess of ACTH. This disorder is also called Grave’s disease or hyperthyroidism.

Correct answer is (d) iodine

The answer is (c) (i) and (iv)

Sensory neurons carry signals from muscles to spinal cord hence statement ii) and iv) are wrong statements

Given statement is false.

Explanation- Symptoms of goiter lead to swelling in neck. Therefore, given statement is false.

Auxin plant hormone makes a stem (or shoot) bend towards light.

Chemotropism in the plants led to the growth of pollen tubes towards the ovules and thus helps in fertilisation of plants and helps in reproduction process.

Given statement is false. 

Explanation- Deficiency of iodine in our diet causes goiter. Therefore, the given statement is false.

In plants, the control and coordination are entirely chemical. Plants coordinate their behaviour against environmental changes with the help of Hormones. Plants have various hormones that help them to coordinate growth and response to the environment. These are the chemical compounds which are released by stimulated cells. Hormones are diffused around the cell. Different hormones in plants are Auxins, Gibberellins, Cytokinins and abscisic acid.

Given statement is false.

Explanation- Insulin helps in the regulation of the blood sugar level. Therefore, the given statement is false.

The pancreas, an organ that lies near the stomach, makes a hormone called insulin to help glucose get into the cells of our bodies. When you have diabetes, your body either doesn't make enough insulin or can't use its own insulin as it should. This causes sugars to build up in the blood. It can be controlled by taking insulin.

Sensitivity to touch:

Wiren tendril of a plant comes in contact with any object, the part of the tendril in contact with the object does not grow as rapidly as that part which is away from the object. This causes the tendril to circle around the object.

The plant gets the support of the object for growing upward without falling.

Timing and amount of hormone released are regulated by feedback mechanisms. If sugar level in the blood rises, cells of pancreas detect and secrete more insulin which leads to the fall of sugar level.

Response → Reflex action.

(i) A receptor to perceive the stimulus.

(ii) A sensory or afferent nerve which carries the message from receptor to spinal cord.

(iii) The neurons of the spinal cord transmit the impulse from afferent neurons to efferent neurons.

(iv) Motor nerve carries a message from the spinal cord to the muscles that show a response.

It is often believed that with the growth of the Television and the internet the print media would be sidelined. However, in India we have seen the circulation of newspapers grow. New technologies have helped boost the production and circulation of newspapers. A large number of glossy magazines have also made their entry into the market. 

The reasons for the growth in Indian newspapers are many. 

1. There is a rise in the number of literate people who are migrating to cities. The Hindi daily ‘Hindustan’ in 2003 printed 64,000 copies of their Delhi’s edition, which jumped drastically in 2005, to 425,000. The reason was that of Delhi’s population of one crore and fprty seven lakh, 52% had come from the Hindi belt of the two states of Uttar Pradesh and Bihar. Of this, 47% have come from a rural background and 60% of them were less than 40 years of age. 

2. The need of the readers in the small towns and villages are different from that of the cities and the Indian language newspapers cater to those needs. Dominant Indian language newspapers such as Malayala Manorama and the Eenadu launched the concept of local news in a significant manner by introducing district and whenever necessary, block editions. Dina Thanthi-, another leading Tamil newspaper, had always used simplified and colloquial language. 

3. The Indian language newspapers have adopted advanced printing technologies and also attempted supplements, pull outs, and literary and nice booklets. 

4. Marketing strategies have also marked the Dainik Bhaskar group’s growth as they carry out consumer contact programmes, door- to-door surveys, and research. Thus, modem mass media has to have a formal structural organisaiton. 

• While English newspapers, often called National Dailies’, circulate across regions, vernacular newspapers have vastly increased their circulation in the states and the mral interland. In order to compete with the electronic media, newspapers, especially English language newspapers have on the one hand reduced prices and on the other hand brought out editions from multiple centres. 

• Change in the role of newspaper production-role of technology. 

• Many feared that the rise in electronic media would lead to a decline in the circulation of print media. This has not happened. Indeed it has expanded. This process has often involved cuts in prices and increasing dependence on the sponsors of advertisements who in turn have a larger say in the content of newspapers. 

•Newspapers have become a consumer product and as long as numbers are big, everything is up for sale.

(i) Element A belongs to group I of the Periodic Table. So, it has I valence electron and it forms unipositive ion by losing its valence electron. Hence, A is a metal.
(ii) This is because element C is in third period while element ts is in second period. We know,that the atomic size increases down the group and decreases along a period.
(iii) Element B is in 2nd period and 3rd group hence it has 3 valence electrons. It loses 3 electrons to achieve nearest inert gas configuration. So, its valency is 3.

Insulin: Regulates sugar metabolism, maintain blood sugar level.

Glucagon: Increases blood sugar level.

1. Glucagon secrated by A cells.
2. Insulin secrated by B cells.
Functions:
Pancreatic hormones stores fat and glucose, as glycogen, after meal.
1.Glucagon maintains the normal blood glucose level between meals to ensure a constant energy supply to our body.
2. Insulin acts as the storage of glucose in the liver and also activates enzymes to promote glycolysis and glycogenesis.

The hormones of pancreas function in an opposite manner. The pancreas releases two hormones, i.e.

(i) Insulin

(ii) Glucagon

Insulin lowers the blood glucose level, while glucagon increases the blood glucose level. Hence, they are antagonistic.

Plants have auxin which is synthesized at the tip of the shoot and it is responsible for the directional growth of the shoot towards the light. In the presence of light auxin is released or is synthesized at the tip of the shoot which helps the cells to grow. When the light comes from one side, auxin diffuse towards the shady part of the shoot. This concentration of auxin elongates the cells of the shady part of the shoot and hence it appears that the plant is bending towards the light.

(i) Plant hormones are known as phytohormones. 

(ii) Auxin is synthesized at the shoot-tip of the plant body.

(iii) Examples :

(a) Auxins play a role in the development of seedless fruits.

(b) Gibberellin stimulates stem elongation.

(c) Ethylene promotes the ripening of fruits.

Three growth hormones in plants are-

(i) Auxin: It is synthesised in the young tip of roots and shoots. It promotes elongation and division of cell and root formation.

(ii)Gibberellins: They help in the growth of the stem.

(iii) Cytokinins: They Promote cell division and delay leaf ageing.

The correct option is C) ASTIGMATISM.