What will happen if mucus is not secreted by the gastric glands?
Gastric glands in stomach release hydrochloric acid, enzyme pepsin and mucus. Mucus protects the inner lining of stomach from the action of hydrochloric acid and enzyme pepsin. If mucus is not released, it will lead to erosion of inner lining of stomach, leading to acidity and ulcers.
(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) 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) Define nutrition. Why is nutrition necessary for an organism ?
(b) What are the different modes of nutrition ? Explain with one example of each mode of nutrition.
(c) Name the mode of nutrition in (i) roundworm, and (ii) Plasmodium.
State whether the following statements are true or false :
(a) During respiration, the plants take C02 and release 02.
(b) Energy can be produced in cells without oxygen.
(c) Fish and earthworm exchange gases during respiration in the same way.
What are the different ways in which glucose is oxidised to provide energy in various organisms ? Give one example of each.
Name the correct substrates for the following enzymes
(a) Trypsin (b) Amylase (c) Pepsin (d) Lipase
In mammals and birds why is it necessary to separate oxygenated and de-oxygenated blood ?
Draw a neat diagram of excretory system of human beings and label the following:
(i) Kidney
(ii) Ureter
(iii) Urinary Bladder
(iv) Urethra
(a) Draw a diagram to show the nutrition in Amoeba and label the parts used for this purpose. Mention any other purpose served by this part other than nutrition.
(b) Name the glands associated with digestion of starch in human digestive tract and mention their role.
(c) How is required pH maintained in the stomach and small intestine?
Name the intermediate and the end products of glucose breakdown in aerobic respiration.
Apart from sunlight and chlorophyll, what other things are required to make food by photosynthesis ?
Which substance is used to remove chlorophyll from a green leaf during photosynthesis experiments ?
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 ?
Name the enzyme present in human saliva. What type of food material is digested by this enzyme ?
Which of the organs perform the following functions in humans ?
(i) Absorption of food
(ii) Absorption of water
What is the name of tiny projections on the inner surface of small intestine which help in absorbing the digested food ?
What is the name of the opening in the human body through which undigested food is thrown out ?
Fill in the following blanks with suitable words :
(a) All green plants are…………..
(b) All non-green plants and animals are…………
(c) Heterotrophs depend on…….. and other……………… for food,
(d) Green plants use……… ,………… and………… to make food.
(e) Iodine turns blue-black on reacting with………………
(a) What is chlorophyll ? What part does chlorophyll play in photosynthesis ?
(b) (i) Which simple food is prepared first in the process of photosynthesis ?
(ii) Name the food which gets stored in plant leaves.
(a) What are autotrophs ? Give one example of autotrophs.
(b) What are the conditions necessary for autotrophic nutrition ?
(a) Photosynthesis converts energy X into energy Y. What are X and Y ?
(b) State the various steps involved in the process of photosynthesis.
a) How do plants obtain food ?
(b) Why do plants need nitrogen ? How do plants obtain nitrogen ?
(a) What is the role of hydrochloric acid in our stomach ?
(b) What is the function of enzymes in the human digestive system ?
(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 ?