LIFE PROCESSES: Short Answer Type Question for Class 10th Chapter 10 JKBOSE/NCERT
Question: What are Enzymes? Name any one enzyme of our digestive system and write its function.
Ans: Enzymes are biological molecules that act as catalysts in biochemical reactions. They are typically proteins that accelerate the rate of specific chemical reactions without being consumed or altered in the process. One enzyme in our digestive system is amylase, which breaks down complex carbohydrates (starches) into simpler sugars
Question: What would be the consequences of a deficiency of haemoglobin in your body?
Ans: A deficiency of haemoglobin in the body can have several consequences. When haemoglobin levels are low, the body may not receive an adequate supply of oxygen, leading to symptoms such as fatigue, weakness, shortness of breath, and pale skin. Severe deficiencies can result in a condition called anaemia.
Question: What is saliva? State its role in the digestion of food.
Ans: Saliva is a watery fluid produced by salivary glands in the mouth. Its role in the digestion of food includes:
1. Moistening and lubricating food, making it easier to swallow.
2. Initiating the breakdown of complex carbohydrates through the action of the enzyme amylase, converting them into simpler sugars.
3. Facilitating the formation of a food bolus, which aids in swallowing.
4. Providing a protective effect on teeth and gums by maintaining oral hygiene
Question: Explain the significance of peristaltic movement that occurs all along the gut during digestion.
Ans: Peristaltic movement is the rhythmic contraction and relaxation of muscles in the gastrointestinal (GI) tract that helps propel food along the digestive system.
Question: Name the components of blood which transport
(i) Food, carbon dioxide and nitrogenous wastes
Ans: (i) The components of blood that transport food, carbon dioxide, and nitrogenous wastes are plasma and red blood cells.
(ii) The component of blood that transports oxygen is red blood cells.
Question: Even when we are not doing any apparent activity, we need energy. Justify giving a reason.
Ans: Even during apparent inactivity, the body requires energy to sustain vital processes. This energy is necessary for maintaining essential bodily functions such as respiration, circulation, digestion, cell repair, and maintaining body temperature.
Question: State any two differences between autotrophic nutrition and heterotrophic nutrition.
Ans: Autotrophic nutrition is the process by which organisms synthesize their organic molecules using inorganic substances like carbon dioxide and water. Heterotrophic nutrition, on the other hand, involves obtaining organic molecules by consuming other organisms or their byproducts.
Autotrophs, such as plants and some bacteria, can produce their food through processes like photosynthesis or chemosynthesis. Heterotrophs, including animals and most microorganisms,
Question: How are water and minerals transported in plants?
Ans: Water and minerals are transported in plants through two main pathways:
Xylem: Water and minerals are primarily transported through xylem vessels in a process called transpiration.
Root pressure: In some plants, root cells actively transport minerals into the xylem, creating a higher solute concentration. This leads to the movement of water into the roots by osmosis, resulting in root pressure that helps push water up the xylem.
Question: How is food transported in plants?
Ans: Food is transported in plants primarily through the phloem tissue, in a process known as translocation.
Question: What are the necessary conditions for autotrophic nutrition and what are its by-products?
Ans: Autotrophic nutrition requires the following conditions:
1. Sunlight: Autotrophs use sunlight as an energy source for photosynthesis.
2. Carbon dioxide: Autotrophs take in carbon dioxide from the atmosphere or water for photosynthesis.
3. Water: Autotrophs absorb water from the soil or surrounding environment for photosynthesis.
4. Chlorophyll: Autotrophs possess chlorophyll or similar pigments to capture light energy for photosynthesis.
The by-products of autotrophic nutrition, specifically photosynthesis, are oxygen and glucose (a form of carbohydrate). Oxygen is released into the atmosphere as a waste product, while glucose is used as an energy source for cellular respiration or stored as starch for later use.
Question: Why do herbivores have longer, small intestines than carnivores?
Ans: Herbivores have longer, small intestines than carnivores due to the nature of their diet. Herbivores consume plant material, which is often more difficult to digest compared to the protein-rich diet of carnivores. Plant material contains complex carbohydrates, such as cellulose, which requires more time and specialized enzymes for breakdown. The longer small intestines in herbivores provide a larger surface area and allow for a longer transit time, enhancing the digestion and absorption of plant-based nutrients.
Question: Which gland secretes a hormone when the blood sugar rises? Name the juices released by this organ.
Ans: The gland that secretes a hormone when blood sugar rises is the pancreas.
The pancreas also releases digestive juices, which aid in the digestion of food. These juices include pancreatic enzymes (such as amylase, lipase, and proteases) that help break down carbohydrates, fats, and proteins, respectively, as well as bicarbonate ions that neutralize stomach acid as food enters the small intestine.
Question: What is the advantage of a four-chambered heart?
Ans: The advantage of a four-chambered heart, as found in mammals and birds, is the separation of oxygenated and deoxygenated blood.
Question: Ventricles have thicker muscular walls than atria. Give reason.
Ans: Ventricles have thicker muscular walls than atria because ventricles are responsible for pumping blood out of the heart, while atria receive blood.