CTET 2011 Question Paper-2 with Answer

Explain: Formation of clot or coagulation of blood is required to stop bleeding. As soon the blood gets coagulated, a clot is formed. On applying alum on the wound, the aluminum and sulfate ions in the alum react with the proteins in the blood causing the coagulation of the blood.

Explain: The reaction that Occurs on dipping an iron nail in copper sulfate solution is as follows:

Fe +CuSO₄ → FesO₄ + Cu

As iron is more reactive than copper, thus, it will displace the copper from the copper sulfate solution and form iron sulfate giving the solution a faded appearance. The copper metal gets deposited over the iron nail giving it a brownish color. Hence, it is a displacement reaction. In this reaction, iron gains oxygen(Oxidation reaction) from copper sulfate solution (oxidizing agent) while copper sulfate loses oxygen (reduction reaction) supplying it to iron (reducing agent). Hence, it is also a redox reaction.

Explain: When we dilute acid, it is always recommended that we should avoid adding water to acid and rather add acid to water in small quantity. This is because when acids are diluted, they release a lot of heat, i.e. it is an exothermic reaction. If we add water to acid, then the acid would boil violently and splash out of the container. It is dangerous as the acid can burn the clothes or skin.

Explain: There are three types of joints, i.e., immovable joint, slightly movable joint and freely-movable joint. Pivot joint, gliding joint, hinge joint saddle joint and ball-and-socket is freely-movable (synovial) joints.

The hinge joint is found in the elbow, knee, and fingers. The pivot joint is found in the neck. Gliding joint is found in the wrist and ankles. Saddle joint is found in the thumb. Ball-and-socket joint occurs in the shoulder and hip.

Explain: Root cap refers to the tissue found at the tip of the root All terrestrial plants possess root cap. Hydrophytes (plants found in water) lack root cap because the roots in these plants are very poorly developed due to availability of plenty of water.

Explain: Plasmolysis is a process in which the water is lost by a cell kept in concentrated solution. When salt or sugar is added to the food item, it makes the environment too concentrated for the microbial cells. The water in the microbial cells is released out due to which the cell membrane shrinks causing the death of the microbes.

Explain: Adrenaline is a hormone secreted from the adrenal glands. It is also referred to as a stress hormone because it helps the body to prepare itself for flight or fight in response to stressful condition. The production of adrenaline is stopped after the end of a stressful condition.

Explain: the Greenhouse effect is a natural phenomenon which helps n keeping the atmosphere of earth warm. The bluehouse gases (CO₂, methane, etc.) absorb the heat of the Sun and the earth and emit it back to the earth’s surface. This increases the atmospheric temperature.

Explain: It is true that blue plants release more oxygen than carbon dioxide during the daytime. t is because photosynthesis occurs in plants during daytime and its rate is the rate of higher photosynthesis. than

The carbon dioxide released by the plants during the daytime is absorbed by the plants for photosynthesis; thus, the amount of net carbon dioxide released by the plants during daytime in the atmosphere is negligible. Plants release oxygen during photosynthesis which Is used for respiration by animals as well as by plants.

Explain: Sieve-tube cells and mammalian erythrocytes (red blood cells) do not contain nucleus. The sieve-tube cells depend upon the companion cells for their activities. RBCs do not need nucleus as they do not reproduce. They just transport cells for hemoglobin.