NIOS Class 12th Biology English Medium Solve Assignment TMA 2021

2. Answer any one of the following questions in about 40 to 60 words.

Ans- A drop of blood is collected by the police from the spot of crime to recognise the culprit. The technique Name is venipuncture ( pathology) is used for this purpose. DNA is that the material which in seperated from the sample by this technique.

Ans- The root system is the descending (growing downwards) portion of the plant axis. When a seed germinates, radicle is the first organ to come of it. It elongates to form primary or the tap root.

(i) Tap root system – It is the root system that develops from the radicle and continues as the primary root (tap root) which gives off lateral roots. These provide very strong anchorage as they are able to reach very deep into the soil. It is the main root system of dicots eg gram, chinarose, neem

(ii) Fibrous root system – In this root system, the primary root is short lived A cluster of slender, fiber-like roots arises from the base of the radicle and plumule which constitute the fibrous root system. They do not branch profusely, are shallow and spread horizontally, hence cannot provide strong anchorage. Fibrous root system is the main root system of monocots, eg maize, grasses, wheat.

Ans-

Ironically, the longest part of the alimentary canal is the small intestine. It is a highly coiled structure of about 7.5 meters in length it is a very narrow tube with a large internal surface area. It is the site of complete digestion in humans. It absorbs digested food completely. It secretes intestinal juice. It receives bile juice from the liver and pancreatic juice From the

pancreas.

The small intestine is divided into three parts:

• Duodenum
• Jejunum
• Ileum

Functions of Small Intestine

• The partially digested food is absorbed by the duodenum of the small intestine along with the digestive juices from the liver,  pancreas and its own walls.
• The liver secretes the bile juice, which converts fat into tiny Droplets so that their digestion becomes easy.
• The pancreas produces pancreatic juice that breaks down fats into fatty acids and glycerol

• The intestinal juice secreted by the walls of the small intestine Breaks down starch and carbohydrates into simple sugars. These Sugars are known as glucose. It also converts the proteins into Amino acids
• All these simple, broken down forms are called the digested food.

5. Answer any one of the following questions in about 100 to 150 words.

Ans- 1. Wash hands regularly. This is especially important after touching surfaces or objects that might be contaminated with respiratory droplets, or after touching persons who are ill with respiratory symptoms. Alcohol hand gels are an adequate substitute when soap and clean water are not readily available.

2. Maintain a clean living environment. If frequently touched surfaces are contaminated with respiratory droplets or secretions:

• Wipe up visible material with paper towels and dispose of used towels in a plastic garbage bag
• Disinfect using any standard household disinfectant
• Take everyday preventive measures including the following
• Do not share eating utensils or drinking containers
• Do not share other personal articles such as toothbrushes or With anyone else
• Staff should separate sleeping cots by 3-6 feet (1-2 meters), if possible, to reduce the potential for spread of respiratory droplets between evacuation center residents.

6. Prepare any one project of the given below:

Ans- Plants deprived of light will lose their color and die. The shoots exposed to “limited/no” sunlight had a yellow/white color due to the fact that photosynthesis could not occur. The lack of sunlight stunted photosynthesis and therefore the sprouts were not able to produce the chlorophyll needed to create a green color.

One important light response in plants is phototropism, which involves growth toward-or away from a light source. Positive phototropism is growth towards a light sources negative phototropism is growth away from light.Most plants grow faster in the evening and at night than they do during the day. Plants can use the products of the days.

Photosynthesis at night to aid in the uptake up water into their cells, which increases the turgor pressure of the cells and drives their enlargement. Day length is a little more complicated, especially in combination with temperature. Many plant species have day length triggers that determine when they grow vegetatively and when they bloom. They may be long-day plants or short-day plants. Some plants do not react to day lengths they are called day-neutral.