Explore topic-wise InterviewSolutions in Current Affairs.

The upward movement of water and minerals from the root towards the top of the plant, is known as the ascent of sap.

Xylem tissue, the water reaches to the leaves

The answer is (C) Leaf

1.Taproot: The root system formed from radicle of the seed, consisting of a distinct primary root and smaller lateral roots. It is the characteristic of dicot plants. 

2. Adventitious root: These roots develop from a source other than the radicle. They arise from nodes, internode, leaves and base of the stem. They are the characteristics of monocot plants.

The respiratory organs of a man is a lung. Some accessory respiratory organs are

1. Nose

2. Pharynx

3. Trachea.

1. Nose: It’s outermost opening, having a pair of external nares (nostrils) followed by a ridge, the nose. Air enters through nostrils. The nostrils contain hair which helps in filtering out the dirt of air. Other foreign particles i.e. germs may lodge on the moist mucous membrane of the nasal passage. The nasal passage leads internally through the internal nares into the pharynx.

2. Pharynx: From the nasal passage air enters the throat through the pharynx. Pharynx contains the openings of windpipe (trachea) called glottis and of food passage (oesophagus) called gullet. Between these two openings, there is a cartilaginous flap, the epiglottis which normally covers the gullet, except when something is swallowed; when it covers the glottis, so that chewed food only enters in the food pipe.

3. Trachea: The trachea is a pipe like structure, which is as long as the neck of the man. Trachea is covered by a semi-circular ring like cartilage on its sides and front. At its upper part is Larynx, the sound box. In the region of the chest, trachea bifurcates into bronchii. Each bronchus enters into the lung of the same side and there, it further divides into many branches-the bronchioles and fine capillaries each entering into air-sacs.

Main respiratory organ: 

Lungs:

Lungs are two in number. These are enclosed in chest box. Each lung has a double wall of pleural membrane. The outer pleural membrane is in contact with muscles of ribs. Each lung is a spongy bag-like structure.

The inner pleural membrane is raised into a large number of sacs, the air sacs which increase the area for exchange of gases. These air sacs, are richly supplied with blood vessels.
Each air sac looks like a cluster of a number of grapes and consists of a number of balloon-like swelling, called alveoli. These alveoli are thin, moist membranes and one cell thick layers. They are in close contact with the extensive capillary network. They act as a functional unit of lungs, in which the exchange of gases takes place.

Root cap protects the delicate growing region of root from injury, caused by scraping against the soil particles.

The answer is (A) Conserving body water

The answer is (B) Ovulation

The answer is (B) less

Nutrition is the whole process by which an organism obtains its food.

The answer is (C) 45

Chemotrophs are the organism, which manufactures their food from in organic substance in the presence of energy derived from inorganic compounds.

Energy is required to perform life processes, which maintain the internal organisation of living organisms.

The answer is (A) Spinal cord

The answer is (A) Coordination and muscular movements

The answer is (A) Cerebrum

Air sacs are the functional units of lungs, which increase the area for exchange of gases.

Finger-like projections of the intestinal wall called Villi.

All those food substances from which organisms get energy, and are able to synthesise cellular substances are called nutrients.

Autotrophs are green plants who manufacture their own food with the help of H₂O, CO₂ and sunlight. Heterotrophs are animals who depend upon autotrophs and are not capable to synthesise their own food.

In plants, metabolism is mostly anabolic in nature. The rate of catabolism is much slower than in animals. Therefore, the rate of accumulation of metabolic wastes is also slower.

Water from soil reaches xylem vessels of the root, because of osmotic pressure gradient and from there it rises up due to pressure. The pressure which causes water to rise up in xylem is called root pressure. It is a vital pressure which pushes water upwards. This is possible when cortical cells alternately pulsate. This root pressure can be understood through a simple experiment.

Experiment: Take a well-watered potted plant and cut the main stem to 7cm above the soil surface and join the cut end of the stem with a glass tube, with the help of a rubber tube joint. Fill some water in a glass tube up to the fixed mark.

Make the rubber joint airtight, by applying molten wax, grease or vaseline. Keep the apparatus for an hour or so. It will be observed that water in glass tube is rising. The rise in a glass tube is due to root pressure, which pushes up the water from root to stem. The magnitude of root pressure is not much.

Medulla oblongata: It forms the connecting limb for the forebrain and the hindbrain. It extends from the pons to the lower surface of the cerebrum. It is more or less triangular and continued behind as a spinal cord. It is hollow from inside, enclosing the fourth ventricle.

Functions: It controls involuntary actions, like coughing, sneezing, vomiting, urinating and defecating. It also controls the rate of heartbeat, breathing movement and blood pressure, by controlling the contraction and relaxation of blood vessels.

Excretion: During cellular respiration various metabolic reactions occur in the body, leading to the formation of various waste products, such as carbon dioxide, urea. These waste products are harmful. Therefore, the removal of these waste products is a must. Thus, excretion is the process of removal of metabolic wastes from the body.

Formation of Urine: This is a physical reaction. Nephrons of the kidney are separate and independent units for the formation of urine.

(i) Three process occur in nephrons:

(ii) Glomerulus ultra-filtration

(iii) Selective re-absorption and

(iv) Tubular excretion.

The blood enters the kidney by the renal artery. After entering the kidney, the renal artery is divided and sub-divided to form a network of blood capillaries. These capillaries form a dense network in the Bowman’s capsule, which is called glomerulus. The blood capillaries entering glomerulus are called afferent arterioles. The diameter of afferent arterioles entering the glomerulus is greater than efferent arterioles, resulting in the increase of blood pressure in the glomerulus. Due to this pressure, the excess of water, urea, glucose uric acid and some salts pass from blood to the Bowman’s capsule. This is glomerulus ultrafiltration. When this filterate passes through the glandular part, glucose, useful salts and some part of water are re-absorbed. This is re-absorption. The liquid left after re­absorption is now called urine. This urine then passes through the ureter into the urinary bladder.

Urinary bladder has involuntary muscles. As soon as the urinary bladder fills up, the involuntary muscles contract and urine are expelled out of the body through the urethra.

The answer is (C) Lizard and Bird

The answer is (C) Proteins

The Crises in the field of Agriculture Farmers face a number of crises. They are mainly loss, cost of production, limited cultivable land, climate change, exploitation of brokers, environmental destruction and health issues, etc. Many of these problems can be overcome if a positive attitude towards agriculture develop. There are many possibilities to solve every problems.

Collect and distribute resources through farmers societies.

C. Adopt integrated Pest control

(a) Apisindica

1. Explant: Any plant part taken for tissue culture

2. Totipotency: Capacity to generate whole plant from any cell

3. MicroPropaaation: Propagation of thousands of plants through tissue culture.

This tendency is not advisable. The increase in population and decrease in the area of crop field and the production of rice may lead the nation to poverty. The goal of food safety will not be attainable.

1. Norman E Borlaug

2. Jaya and Ratna

The five hybrid varieties of crop plants which have been developed in India are:

Crop Plant Hybrid Variety

1. Wheat – Sonalika and Kalian sona

2. Rice – Jaya and Ratna

3. Cauliower – Pusa shubra and Pusa snowball K-1

4. Cow pea – Pusa komal

5. Mustard – Pusaswarnim

• polyhouse farming – (b), (c)
• Precision farming – (a), (d)

The native varieties exist in a particular locality by acquiring natural resistance and adaptations to the climate, availability of food, nature of soil etc., though they have low productivity.

The native varieties have high resistance to diseases and environmental conditions. The extinction of native varieties leads to the depletion of our biodiversity. New varieties can be developed only from the native varieties.

Domestication was a gradual process that began about 12,000 years ago.

• Farmer’s opinion is right.
• Indigenous varieties of a locality are varieties that acquire natural immunity by adapting to the climate, the availability of food, soil texture of the place etc.
• We can develop new high quality varieties only from indigenous varieties.

The cost of making a polyhouse is very high. But the yield from the crops will increase substantially.

Horticulture

b. Excessive use of chemical pesticide

• Hydroponics is the technique by which plants are grown in nutrient solution
• In aeroponics plants are grown in such a way that their roots are penetrating towards air and nutrients are directly sprayed to their roots.

a. Jersey, Murrah 

b. Athulya, Muscovy 

c. Naran, Kara 

d. Grey giant, Ankora 

e. Muga, Tusser 

f. Mellifera, Kolan

a. Polyhouse farming

b. hydroponics

c. precision farming

Bhadawari, Jaffrabadi, Marwari, pashmina, malabari, Beetance.

1. Apis indica

2. It helps to increase Honey yield, pollination efficiency and crop yield.

Lactobacillus – others are nitrogen fixing bacteria.

Science has proved that cultivation is possible in the absence of soil, for example aeroponics and hydroponics. In hydroponics, plants are grow in nutrients solution. In aeroponics, plants are grow in such a way that their roots grow into air and nutrients are sprayed directly on roots.

Bees are the pollination of many crops. Keeping beehives in crop fields during flowering period increases pollination and improve the honey yield. It is beneficial both for crop yield and honey yield.

Microbial fertilizers contains micro organisms that increase the fertility of soil. 

They increase the amount of growth promoting factors in soil.

Eg: Rhizobium Azetobacter raise the amount of Nitrogen in the soil.