What is the name of tiny projections on the inner surface of small intestine which help in absorbing the digested food ?
Villi.
(a) Name the pigment in leaves which absorbs sunlight energy.
(b) What is the colour of this pigment ?
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?
Name the enzyme present in human saliva. What type of food material is digested by this enzyme ?
What is the name of those cells in the leaf of a plant which control the opening and closing of stomata?
Apart from sunlight and chlorophyll, what other things are required to make food by photosynthesis ?
a) How do plants obtain food ?
(b) Why do plants need nitrogen ? How do plants obtain nitrogen ?
(a) Which part of the body secretes bile ? Where is bile stored ? What is the function of bile ?
(b) What is trypsin ? What is its function ?
Name one substance which is produced in anaerobic respiration by an organism but not in aerobic respiration.
What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.
Draw a neat diagram of excretory system of human beings and label the following:
(i) Kidney
(ii) Ureter
(iii) Urinary Bladder
(iv) Urethra
A Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment. :
In addition to carbon dioxide and water, state two other conditions necessary for the process of photosynthesis to take place.
All the animals can be divided into three groups on the basis of their eating habits. Name the three groups.
What is the scientific name of the animals which are :
(i) only meat eaters ?
(ii) only plant eaters ?
(iii) both, plant and meat eaters ?
What is the name of tiny projections on the inner surface of small intestine which help in absorbing the digested food ?
(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 are heterotrophs ? Give one example of heterotrophs.
(b) What is the difference between autotrophic nutrition and heterotrophic nutrition ?
(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 following :
(a) The process in plants which converts light energy into chemical energy.
(b) Organisms that cannot prepare their own food.
(c) Organisms that can prepare their own food.
(d) The cell organelle where photosynthesis occurs.
(e) The cells which surround a stomatal pore.
(f) An enzyme secreted by gastric glands in stomach which acts on proteins.
(a) Name the main organs of the human digestive system. Also name the associated glands.
(b) How do carbohydrates, fats and proteins get digested in human beings ?
What are the different ways in which glucose is oxidised to provide energy in various organisms ? Give one example of each.
Explain why, when air is taken in and let out during breathing, the lungs always contain a residual volume of air.
State the three common features of all the respiratory organs like skin, gills and lungs.