Find CBSE class 9th science solved guess paper specially designed for SA-I Exam 2016. This paper is having unique solutions for each and every questions.This paper is a collection of questions from the previous year question papers,along with fresh new questions and has been framed keeping the Students perspective in mind. This will help the Students by building a sound concept before their SA-I Examination.Over all this paper will help you topractice all the SA-I syllabus in one time
Have a look over some sample questions from the complete paper:
Question. Explain whether air is a compound or a mixture with reason.
The composition of air is not fixed, the components of air can be obtained by physical method, and the melting and boiling points of air is not fixed as its composition is variable.
Question. What is the SI unit momentum?
SI unit of momentum is kg-ms‒1.
Question. What is the function of chromosomes in a cell?
Chromosome contains the genetic material that is required by the organism to develop and grow. The chromosomes direct the sequences of proteins formed in our body and also maintain the order of DNA.
Question. Find the displacement of a sportswoman after 60 seconds, if she completes one round of a circular track of radius 5 m in 30 s?
In 30 seconds she complete one circular track, therefore in 60 seconds she will complete two circular tracks. So, her displacement will be zero.
Question. Explain what happens when iron fillings are heated with sulphur powder. Is the substance formed is compound or mixture?
When iron fillings are heated with sulphur powder Black coloured solid iron (II) sulphide (FeS) will be formed. The substance formed is compound.
Question. Why lysosomes are also known as "suicidal bags of the cell"?
Lysosomes are cellular organelles that contain digestive enzymes that break down waste materials, foreign material and cellular debris. Lysosomes are capable of digesting nucleic acid, polysaccharides, fats, and proteins. Along with them lysosomes also digest or damage its own cells by its own enzymes, which lead to cell death. This process is called as autolysis. Hence lysosomes are also called as suicide bags
Question. State three preventive and control measures taken before agricultural products are stored for future use.
Three preventive and control measures taken before agricultural products are stored for future use are:
(i) Agricultural products should be cleaned properly.
(ii) Agricultural products should be properly dried in the sunlight and shade before storage.
(iii) Fumigation using chemicals should be done in order to kill pests.
Question. Explain the terms evaporation and sublimation? Explain why water kept in an earthen pot becomes cool during summer.
Evaporation: The process where a liquid changes into vapor at any temperature below its boiling point is evaporation .Evaporation is a surface phenomenon.
Sublimation: The process, where a solid, on heating, directly changes into gas without changing into liquid, and a gas, on cooling, directly changes to solid without changing into liquid.
In an earthen pot, water gets evaporated quickly through the pores. This Cooling is caused by evaporation and some heat energy is utilized during the process of evaporation. As, this energy is taken from the water itself so, it leads to a lowering of temperature of water inside the earthen pot.
Question. What are connective tissues? Also explain its various functions.
Connective tissues are fibrous in nature. They include blood, bone, ligament, cartilage, areolar and adipose tissues. These help in binding other tissues together. They also provide support to other tissues.
Bone cells are embedded in a hard matrix composed of calcium and phosphorus compounds. Bones anchor the muscles.
Blood has plasma and blood cells. The blood cells suspended in the plasma include RBC’s, WBC’s and platelets. Blood flows within blood vessels, and transports gases, digested food and hormones to different parts of the body.
Ligaments are tough and elastic. They provide strength and flexibility. Tendons are tough and non-elastic, and provide great strength and limited flexibility.
Areolar connective tissue has irregular shaped cells and is found between the skin and muscles, around blood vessels and nerves.
Cartilage has widely spaced cells suspended in a matrix of proteins and sugars. It is found in the nose, ears, and the rings of the trachea to give flexibility.
Adipose tissue contains cells filled with fat globules. It is found below the skin and acts as an insulator.
Question. A mixture of hydrogen chloride, common salt and marble powder is mixed with water and then filtered. The residue left on the filter paper will be
(a) Hydrogen chloride
(b) Common salt
(c) Marble powder
(d) Common salt and marble powder
(b):Common salt and hydrogen chloride dissolves in water whereas marble powder is insoluble in water so, only marble powder will be left as residue on filter paper.