IMPORTANT QUESTIONS OF BIO CH-1

Q1(a) Explain with the help of diagram, how amoeba takes its nutrition.
(b) Assume that you are a veterinary surgeon and you had removed a
 good length of the small intestine of a bear that was suffering from a
intestinal tumor. Now, would you suggest a plant based or an meat
based diet for the bear after its recovery ? Give reason for your answer
ans1(a)



(b)I would suggest meat based diet because small intestine can easily
absorb it but plants contain cellulose which is not easy to be absorbed.
Q2(a)Draw the diagram of human heart and label it.
 (b) Which blood vessel  carries away oxygenated blood from the heart
(c) Which blood vessel receives de-oxygenated blood from the lower part
 of our body.
ans2(a)


(b)Aorta
(c)Vena Cava of lower body
Q3(a)The stomatal opening is controlled by guard cells. If the stomatal
opening is to remain open how should the guard cells be ?
(a) stretched (b) swollen (c) rigid (d) shrunk
Ans3-(b)Swollen
Q4(a) Draw the human respiratory system and label it.
 (b) During breathing cycle what is the advantage of residual volume of air
 in lungs ? Explain.
ans4(a)

(b)During the breathing cycle,the lungs always have a residual volume of gases
so that there is sufficient time  for oxygen to be absorbed and carbondioxide
to be released.
Q5-Other than light, which of the following are also essential for photosynthesis ?
(a) carbon di-oxide, water, chlorophyll (b) carbon di-oxide, chlorophyll
(c) carbon, water, minerals, chlorophyll (d) carbon di-oxide, water, hormones
ans-(a)
Q6The guard cells are also capable of photosynthesis because they have :
 (a) cytoplasm, nucleus, centrioles (b) cytoplasm, nucleus, centrosome
(c) cytoplasm, nucleus, chromosomes (d) cytoplasm, nucleus, chloroplasts
Ans6-(d)
Q7 Explain why ventricles have thick muscular walls than the atria ?
Ans-Ventricles have thick muscular walls than atria because
Q8(a) Define excretion. Name any two substances that are selectively
reabsorbed. (b) Draw and label the human excretory system.
ans8-(a)The biological process of the removal of harmful metabollic
wastes from the  body is called excretion.Glucose,amino acids,salts
and water are re-absorbed.
(b)
 

Q9In human alimentary canal name the site of complete digestion of
various components of food. How?
Ans9-The site of comlete digestion in human alimentary canal is the
small intestine.It recieves the secretions of the liver and pancreas
for this purpose.The food coming from the stomach is acidic and
has to be made alkaline for pancreatic enzymes to act.Bile juice
 from the liver acts on the fats.The Bile salt acts upon the fat globules
and helps enzymec to act upon them.Pancreatic enzymes like trypsin
act upon protiens and lypase on the fats.The protiens are converted
into amino acid, carbohydrates into glucose and fats into fatty acids
and glycerol.The inner lining of the small intestine has villi which
increase the surface area of absorption.The blood vessels in it take
 up the absorbed  food and distributed in the body.
Q10-Explain the process of nutrition.
Ans10-
1.Firstly we take in food through mouth and crush it and mix
it with saliva as the food  pipe is muscular and soft.The salivary
amylase,an enzyme,break down the starch.The food now passes
through oesophagus by peristaltic movements.
2.The food reaches the stomach.The walls of the stomach help
in digesting foofd by mixing it with digestive juices.The gastic
glands in the stomach release HCl ,protien digesting enzyme pepsin
and mucus.Pepsin can work only in the presence of HCl .Now the food moves
into small intestine by the sphincter muscles.
3.The small intestine recieves the secretions of the liver and pancreas
for digesting food.The food coming from the stomach is acidic and
has to be made alkaline for pancreatic enzymes to act.Bile juice
 from the liver acts on the fats.The Bile salt acts upon the fat globules
and helps enzymec to act upon them.Pancreatic enzymes like trypsin
act upon protiens and lypase on the fats.The protiens are converted
into amino acid, carbohydrates into glucose and fats into fatty acids
and glycerol.
4.The inner lining of the small intestine has villi which
increase the surface area of absorption.The blood vessels in it take
 up the absorbed  food and distributed in the body.
5.The unabsorbes food reaches the large intestine where more villi
absorb water and rest of the material is removed from the body via the
anus.