Multiple Choice Questions
- Where is bile produced ?
(a) Gall bladder
- Kidneys in human beings are a part of the system for-
(a) nutrition (c) excretion
(b) respiration. (d) transportation.
- The xylem in plants is responsible for
(a) transport of water
(b) transport of food
(c) transport of amino acids
(d) transport of oxygen.
- The autotrophic mode of nutrition requires
(a) Carbon dioxide and water
(d) All of these.
- The breakdown of pyruvate to give carbon dioxide, water and energy takes place in
(a) cytoplasm. (b) mitochondria
(c) chloroplat f(d) nucleus.
- Respiration is a process in which
(a) Energy is stored in the form of ADP
(b) Energy is released and stored in the form of ATP
(c) Energy is used up
(d) Energy is not released at all.
- Movement of food through oesophagus is due to
(a) Lubrication of saliva
(c) Gravitational pull
(d) All of the above.
- Which of the following has the longest small intestine?
- Villi are present in
(a) stomach. (b) pancreas
(c) small intestine (d) oesophagus.
- Which of the following metal is associated with haemoglobin ?
Ans. 1. (b), 2. (c), 3. (a), 4. (d), 5. (b), 6. (b), 7. (b), 8. (c), 9. (c), 10. (d).
Ans. 1. (b), 2. (c), 3. (a), 4. (d), 5. (b), 6. (b), 7. (b), 8. (c), 9. (c), 10. (d).
Fill in the Blanks
- The saliva contains an enzyme called …………..
- Brushing of teeth removes ………… which covers the teeth due to eating food.
- The ………… is the site of complete digestion of carbohydrates, proteins and fats.
- Carnivores like tiger have a shorter………… as meat is easier to digest.
- Carbon and energy requirements of an autotrophic organism are fulfilled by …………..
- The transport of soluble products of photosynthesis from leaves to other parts is
- Removal of wastes from the body is called …………
Ans. 1. Salivary amylase, 2. plaque, 3. small intestine, 4. small intestine, 5. photo synthesis, 6. translocation, 7. excretion.
- Green plants are heterotrophs.
- Amoeba is a unicellular organism.
- Fungi break the food outside the body and then absorb it.
- Anaerobic respiration takes place in the presence of oxygen.
- The inner lining of small intestine has finger-like projections called villi.
Ans. 1. False, 2. True, 3. True, 4. False, 5. True.
Match the Columns
- Column ‘A Column ‘B’
- Respiration (a) Sunlight
- Rings of cartilage. (b) Oxidation
- Photosynthesis. (c) Throat
- Amphibians. (d) Cellular vacuoles
- Plant waste. (e) Three-chambered heart
- Nephron. (f) Structural unit
Ans. 1. (b), 2.→ (c), 3. (a), 4. → (e), 5. → (d), 6. → (f).
- Column ‘A’ Column ‘B’
- Sphygmomanometer (a) Excretion
- Kidney. (b) Gaseous exchange
- Smoking. (c) Blood pressure
- Stomata. (d) Photosynthesis.
- Chlorophyll. (e) Lungs cancer
Ans. 1. (c), 2. → (a), 3. → (c), 4. (b), 5. (d).
Answer in one Word/Sentence
- Name the respiratory organ in fishes.
- Name an organ which is a part of two body systems.
Ans. Pancreas, which is a part of Endocrine system and Digestive system.
- In which form glucose is stored for longer duration in plant cells?
Ans. As starch.
- What is analogous to starch in human body to store food for longer te?
- What is the mode of nutrition in fungi?
Ans. Saprophytic or Parasitic nutrition.
- How do aquatic plants get oxygen for photosynthesis?
Ans. Through the process of diffusion.
- What is the respiration that takes place in absence of oxygen called?
Ans. Anaerobic respiration.
- What is the pressure of blood in artery during ventricular contraction called?
Ans. Systolic pressure.
- Write the name of pigment found in leaf of green plants
- Sweating in animals is equivalent to what in plants?
Very Short Answer Type Questions
- 1. Define nutrition.
Ans. The process of taking in food and utilising it is called nutrition.
- 2. What is autotrophic nutrition ?
Ans. The mode of nutrition in which an organism makes its own food from simpler inorganic substances like CO₂ and water with the help of sunlight is called autotrophic nutrition.
- 3. What is the role of Saliva in digestion of food?
Ans. The saliva moistens the food for easy swallowing. It contains a digestive enzyme
called salivary amylase, which breaks down starch into sugar.
- 4. What are the necessary conditions for autotrophic nutrition and what are its by-products?
Ans. Autotrophic nutrition takes place through the process of photosynthesis. Presence of carbon dioxide, water, chlorophyll and sunlight are the necessary conditions for autotrophic nutrition. Carbohydrates (food) and oxygen are the by-products of photosynthesis.
- 5. Describe double circulation in human beings. Why is it necessary ?
Ans. During a single cycle, blood goes twice in the heart which is known as double circulation. It is necessary in human beings to separate oxygenated and deoxygenated blood because this makes their circulatory system more efficient and helps in maintaining constant body temperature.
- 6. How are fats digested in our bodies? Where does this process take place ?
Ans. Fats are present in the form of large globules in the small intestine. The bile salts from liver break the large fat globules into smaller globules so that the pancreatic enzyme
lipase can easily act on them. This is called emulsification of fats. The walls of the small intestine contain glands which secrete intestinal juice. The enzymes present in it finally convert the fats into fatty acids and glycerol. The process of digestion of fats takes place in small intestine.
- 7. What are the methods used by plants to get rid of the excretory products?
Ans. Plants can get rid of excess of water by transpiration. Many plant waste products are stored in cellular vacuoles. Waste products are also stored in leaves that fall off. Other waste products are stored as resins and gums, especially in old xylem. Plants also excrete some waste substances into the soil around them. Oxygen released during photosynthesis is also a waste product for plants.
- 8. What are the components of transport system in highly organised plants?
Ans. In highly organised plants, there are two types of conducting tissues-xylem and phloem. Xylem conducts water and minerals obtained from the soil (via roots) to the rest of the plant. Phloem transports food materials from leaves to different parts of the plant body.
- 9. Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds ?
Ans. It is necessary to separate deoxygenated and oxygenated blood to maintain efficient supply of oxygen into the body. This system is essential in animals that have high energy need. For example, mammals and birds constantly use this energy to maintain their body temperature.
- 10. How is the small intestine designed to absorb digested food?
Ans. The inner lining of small intestine has numerous tiny finger-like projections called villi. These villi increase the surface area for more efficient food absorption. Within these villi, many blood vessels are present that absorb the digested food and carry it to the blood stream. From the blood stream, the absorbed food is delivered to each and every cell of the body.
- 11. What is the role of the acid in our stomach ?
Ans. The gastric glands in the wall of the stomach release hydrochloric acid, a protein digesting enzyme called pepsin and mucus. The hydrochloric acid creates an acidic medium which facilitates the action of the enzyme pepsin. The hydrochloric acid also kills many bacteria and other micro-organisms that enter along with the food.
- 12. From where do plants get each of the raw materials required for
Ans. For photosynthesis plants get carbon dioxide (CO₂) gas from atmosphere photosynthesis. through stomata, water absorbed from soil and solar energy from sun.
Short Answer Type Questions
- 1. What are the differences between transport of materials in xylem and phloem? Ans. Differences are as follows:
- 2. What would be the consequences of deficiency of haemoglobin in our body?
Ans. Haemoglobin is the respiratory pigment that transports oxygen to the body cells for cellular respiration. Therefore, deficiency of haemoglobin in blood can affect the oxygen supplying capacity of blood. This can lead to deficiency of oxygen in the body cells. It ca also lead to a disease called anaemia.
- 3. What are the components of the transport system in human beings ? What are the functions of these components ?
Ans. The main components of the transport system in human beings are the heart, the blood and the blood vessels.
Heart Heart pumps oxygenated blood throughout the body. It receives deoxygenated blood from various body parts and sends this impure blood to the lungs for oxygenation.
Blood-It helps in the transport of oxygen, nutrients and excretion of CO₂ and nitrogenous wastes.
Blood Vessels (arteries, veins and capillaries) They carry blood either away from the heart to various organs or from various organs back to the heart.
- 4. How are the lungs designed in human beings to maximize the area for exchange of gases?
Ans. Lungs contain several balloon-like structures called alveoli which provide a surface for the exchange of gases. The walls of the alveoli contain an extensive network of blood vessels. When we breathe in, we lift our ribs and flatten our diaphragm, and thus the ches cavity becomes larger. Because of this, air is sucked into the lungs and fills the expanded alveoli. The blood brings CO₂ from the rest of the body for release into the alveoli and the oxygen in the alveolar air is taken up by the blood in alveolar blood vessels to be transportad
- 5. Draw a well labelled diagram of human excretory system.
- 1. What are the differences between autotrophic nutrition and heterotrophic nutrition ?
- 2. How are water and minerals transported in plants?
Ans. Water and minerals are transported through xylem cells from soil to the leaves. The xylem cells of roots, stem and leaves are interconnected to form a conducting channel that reaches all parts of the plant. The root cells take ions from the soil. This creates a difference in the concentration of these ions between the root and the soil. Thus there is a steady movement of water into root xylem, creating a column of water that is steadily pushed upwards. An osmotic pressure is formed and water and minerals are transported from one cell to the other due to osmosis. A continuous loss of water takes place from leaves due to evaporation of water molecules or transpiration. Thus, a suction pressure is created due to which water is forced into the xylem cells of roots. The effect of root pressure in transport of water is more important at night. During the day, the transpirational pull becomes the major driving force in the movement of water in the xylem.
- 5. What are the differences between aerobic and anaerobic respiration ? Name some organisms that use the anaerobic mode of respiration.
- 6. Differentiate an artery and vein.
Ans. Differences between an artery and vein:
- 7. Compare the functioning of alveoli in the lungs and nephrons in the kidneys with respect to their structure and functioning.