1.
Cell wall is present in?
Correct Answer
A. Plant cells
Explanation
The cell wall is a rigid outer layer that provides support and protection to plant cells. It is composed of cellulose and other structural components. Animal cells do not have a cell wall, instead they have a flexible cell membrane. Unicells, which are single-celled organisms, may or may not have a cell wall depending on their specific characteristics. Therefore, the correct answer is plant cells, as they are the primary type of cells that possess a cell wall.
2.
Cell wall is made up of?
Correct Answer
B. Cellulose
Explanation
Cellulose is the correct answer because it is the main component of the cell wall. Cell walls provide structural support and protection to plant cells, and cellulose is a complex carbohydrate that forms a strong and rigid network of fibers. Glucose, starch, and fructose are all types of carbohydrates, but they do not make up the cell wall.
3.
What function does cellulose perform in a plant cell?
Correct Answer
B. Provides mechanical strength to the plant
Explanation
Cellulose provides mechanical strength to the plant. Cellulose is a complex carbohydrate that forms the cell wall in plant cells. It provides rigidity and structural support, allowing the plant to maintain its shape and withstand external forces. Without cellulose, plant cells would be unable to maintain their structural integrity, making them more susceptible to damage and collapse. Therefore, cellulose plays a crucial role in providing mechanical strength to plant cells.
4.
Glycosidic bonds present in the cellulose are
Correct Answer
B. β- 1,4
Explanation
Glycosidic bonds present in cellulose are β-1,4. This means that the glucose molecules in cellulose are linked together through a β-glycosidic bond at the first carbon of one glucose molecule and the fourth carbon of the next glucose molecule. This type of bond formation creates long, straight chains of glucose molecules, which are important for the structural integrity of cellulose.
5.
Starch is joined together by?
Correct Answer
D. Glycosidic bonds
Explanation
Starch is a polysaccharide made up of glucose molecules. These glucose molecules are joined together by glycosidic bonds, which are covalent bonds formed between the carbon atoms of adjacent glucose molecules. This bond allows starch to form a long, branched chain structure, making it suitable for energy storage in plants.
6.
Which of the following cannot be used as a starch in the sauce?
Correct Answer
B. Butter
Explanation
Butter cannot be used as a starch in the sauce because it is a fat, not a carbohydrate like the other options. Starches are used to thicken sauces and provide a creamy texture, whereas butter is used for flavor and adding richness.
7.
Where do most carbohydrates come from?
Correct Answer
B. Plants
Explanation
Most carbohydrates come from plants. Plants are able to produce carbohydrates through the process of photosynthesis, where they convert sunlight, water, and carbon dioxide into glucose. Carbohydrates are a primary source of energy for both plants and animals, and they are found in a variety of plant-based foods such as fruits, vegetables, grains, and legumes. While animals can also contain carbohydrates in their diets, the majority of dietary carbohydrates come from plant sources.
8.
Starch is a?
Correct Answer
B. Polysaccharides
Explanation
Starch is a complex carbohydrate made up of many glucose molecules bonded together. It is a polysaccharide, which means it is composed of multiple sugar molecules. Monosaccharides are single sugar molecules, while disaccharides are made up of two sugar molecules. Therefore, neither monosaccharides nor disaccharides accurately describe starch.
9.
Autoignition temperature of starch is
Correct Answer
C. 410 °C
Explanation
Starch is a carbohydrate that is commonly found in plants and is used as a source of energy. The autoignition temperature refers to the minimum temperature at which a substance can ignite without an external ignition source. In the case of starch, the correct answer is 410°C, meaning that it will spontaneously ignite at this temperature. This high autoignition temperature suggests that starch is relatively stable and resistant to ignition, requiring a significant amount of heat to start a fire.
10.
Cellulose consists of
Correct Answer
A. Long polymer chains of glucose
Explanation
Cellulose is a complex carbohydrate that forms the structural component of plant cell walls. It is composed of long polymer chains of glucose molecules linked together through beta-1,4-glycosidic bonds. These chains are arranged in a linear fashion and are held together by hydrogen bonding, resulting in a strong and rigid structure. Therefore, the correct answer is "long polymer chains of glucose."