(a) Why is small intestine in herbivores longer than in carnivores ?
(b) What will happen if mucus is not secreted by the gastric glands ?
(c) What causes movement of food inside the alimentary canal ?
(a) Herbivores eat only plants so they need a longer small intestine to allow the cellulose present in the plants to be digested completely.
(b) If mucus is not secreted, hydrochloric acid will cause the erosion of inner lining of stomach leading to the formation of ulcers in the stomach.
(c) The contraction and expansion movements of oesophagus also called peristaltic movements pushes the food down into the elementary canal.
What is the name of tiny projections on the inner surface of small intestine which help in absorbing the digested food ?
State the role of the following in human digestive system :
(i) Digestive enzymes (ii) Hydrochloric acid (iii) Villi
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 labelled diagram of the respiratory system of human beings with diaphragm at the end of expiration.
(b) List four conditions required for efficient gas exchange in an organism.
(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?
Which of the following type of energy is used by living organisms to perform vital life processes ?
Kinetic energy, Chemical energy, Potential energy, Nuclear energy
Name the enzyme present in human saliva. What type of food material is digested by this enzyme ?
(a) Define a nutrient. Name four important nutrients present in our food.
(b) What are the various types of heterotrophic nutrition ?
a) How do plants obtain food ?
(b) Why do plants need nitrogen ? How do plants obtain nitrogen ?
Name the areas in a woody stem through which respiratory exchange of gases takes place.
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.
In human alimentary canal, name the site of complete digestion of various components of food. Explain the process of digestion.
A Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment. :
In the experiment "Light is essential for photosynthesis", why does the uncovered part of the leaf turn blue-black after putting iodine solution?
Arrange the following processes involved in the nutrition in animals in the correct order (in which they take place):
Assimilation, Egestion, Ingestion, Absorption, Digestion
(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.
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…………..
What type of respiration takes place in human muscles during vigorous physical exercise ? Give reason for your answer.
Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms ?