(a) How does carbon dioxide from the air enter the leaves of a plant to be used in photosynthesis ?
(b) How does water from the soil reach the leaves of a plant to be used in photosynthesis ?
(a) The carbon dioxide gas enters the leaves of the plants through the stomata present on their surface.
(b) The water required by the plants for photosynthesis is absorbed by the roots of the plants from the soil through the process of osmosis. The absorbed water is then transported upward through the xylem vessels to the leaves where it reaches the photosynthetic cells and utilized in photosynthesis.
What is the name of tiny projections on the inner surface of small intestine which help in absorbing the digested food ?
(a) Name the raw materials required for photosynthesis. How do plants obtain these raw materials ?
(b) What are the various conditions necessary for photosynthesis ?
(c) Name the various factors which affect the rate of photosynthesis in plants.
State the role of the following in human digestive system :
(i) Digestive enzymes (ii) Hydrochloric acid (iii) Villi
Name the final product/products obtained in the anaerobic respiration, if it takes place :
(a) in a plant (like yeast).
(b) in an animal tissue (like muscles).
Write correct sequence of four steps of method for the preparation of temporary mount of a stained leaf peel.
Arrange the following processes involved in the nutrition in animals in the correct order (in which they take place):
Assimilation, Egestion, Ingestion, Absorption, Digestion
Fill in the following blanks with suitable words :
(a) The organs of respiration in man are the…………..
(b) The actual exchange of gases takes place in the………… of the lungs.
(c) ………………in the lungs provide a very large surface area for gaseous exchange.
(d) Yeast undergoes……….. respiration whereas Amoeba undergoes………….. respiration.
(e) Gills are the breathing organs in…………..
State the three common features of all the respiratory organs like skin, gills and lungs.
What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.
In human alimentary canal, name the site of complete digestion of various components of food. Explain the process of digestion.
Name the green dot like structures in some cells observed by a student when a leaf peel was viewed under a microscope. What is this green colour due to?
(a) What is meant by breathing? What happens to the rate of breathing during vigorous exercise and why?
(b) Define translocation with respect to transport in plants. Why is it essential for plants? Where in plants are the following synthesised?
(i) Sugar (iii) Hormone
(a) What criteria can be used to decide whether something is alive ?
(b) What is meant by life processes ? Name the basic life processes common to all living organisms which are essential for maintaining life.
(a) What is the role of hydrochloric acid in our stomach ?
(b) What is the function of enzymes in the human digestive system ?
Name the substance whose build up in the muscles during vigorous physical exercise may cause cramps.
Describe the process of respiration in the following parts of a plant :
(a) Root (b) Stem (c) Leaves