Life Processes | Top 20 MCQs | Class-10th | Part-2 | Ch-6 | Science | CBSE | NCERT | For term 1 exam

If salivary amylase is lacking in the saliva, which of the following events in the mouth cavity will be affected?

(a) Proteins breaking down into amino acids

(b) Starch breaking down into sugars

(c) Fats breaking down into fatty acids and glycerol

(d) Absorption of vitamins

Which part of alimentary canal receives bile from the liver?

(a) Stomach

(b) Small intestine

(c) Large intestine

(d) Oesophagus

Which is the correct sequence of parts in human alimentary canal?

(a) Mouth → stomach → small intestine → oesophagus → large intestine

(b) Mouth →oesophagus → stomach → large intestine → small intestine

(c) Mouth → stomach → oesophagus → small intestine → large intestine

(d) Mouth → oesophagus → stomach → small intestine → large intestine

In which of the following groups of organisms, food material is

broken down outside the body and absorbed?

(a) Mushroom, green plants, Amoeba

(b) Yeast, mushroom, bread mould

(c) Paramecium, Amoeba, Cuscuta

(d) Cuscuta, lice, tapeworm

In which part of the alimentary canal food is finally digested?

(a) Stomach

(b) Mouth cavity

(c) Large intestine

(d) Small intestine

Select the correct statement

(a) Heterotrophs do not synthesise their own food

(b) Heterotrophs utilise solar energy for photosynthesis

(c) Heterotrophs synthesise their own food

(d) Heterotrophs are capable of converting carbon dioxide and

water into carbohydrates

Choose the function of the pancreatic juice from the following

(a) trypsin digests proteins and lipase carbohydrates

(b) trypsin digests emulsified fats and lipase proteins

(c) trypsin and lipase digest fats

(d) trypsin digests proteins and lipase emulsified fats

Which of the following statement(s) is (are) true about respiration? 

(i) During inhalation, ribs move inward and diaphragm is raised 

(ii) In the alveoli, exchange of gases takes place i.e., oxygen from alveolar air diffuses into blood and carbon 

dioxide from blood into alveolar air 

(iii) Haemoglobin has greater affinity for carbon dioxide than oxygen 

(iv) Alveoli increase surface area for exchange of gases 

(a) (i) and (iv) 

(b) (ii) and (iii) 

(c) (i) and (iii) 

(d) (ii) and (iv)

When air is blown from mouth into a test-tube containing lime water, the lime water turned milky due 

to the presence of 

(a) oxygen 

(b) carbon dioxide 

(c) nitrogen 

(d) water vapour

During respiration exchange of gases take place in 

(a) trachea and larynx 

(b) alveoli of lungs 

(c) alveoli and throat 

(d) throat and larynx

Which is the correct sequence of air passage during inhalation?

(a) Nostrils → larynx → pharynx → trachea     → lungs

(b) Nasal passage → trachea → pharynx         → larynx → alveoli

(c) larynx → nostrils → pharynx → lungs

(d) Nostrils → pharynx → larynx → trachea     → alveoli

Single circulation i.e., blood flows through the heart only once during one cycle of passage through the 

body, is exhibited by 

(a) Labeo, Chameleon, Salamander 

(b) Hippocampus, Exocoetus, Anabas 

(c) Hyla, Rana, Draco 

(d) Whale, Dolphin, Turtle

 Which of the following statement (s) is (are) true about heart? 

(i) Left atrium receives oxygenated blood from different parts of body while right atrium receives 

deoxygenated blood from lungs 

(ii) Left ventricle pumps oxygenated blood to different body parts while right ventricle pumps 

deoxygenated blood to lungs 

(iii) Left atrium transfers oxygenated blood to right ventricle which sends it to different body parts 

(iv) Right atrium receives deoxygenated blood from different parts of the body while left ventricle pumps 

oxygenated blood to different parts of the body 

(a) (i) 

(b) (ii) 

(c) (ii) and (iv) 

(d) (i) and (iii)

n which of the following vertebrate group/groups, heart does not pump oxygenated blood to different 

parts of the body? 

(a) Pisces and amphibians 

(b) Amphibians and reptiles 

(c) Amphibians only 

(d) Pisces only

What prevents backflow of blood inside the heart during contraction? 

(a) Valves in heart 

(b) Thick muscular walls of ventricles 

(c) Thin walls of atria 

(d) All of the above

Choose the correct statement that describes arteries. 

(a) They have thick elastic walls, blood flows under high pressure; collect blood from different organs and bring it back to the heart 

(b) They have thin walls with valves inside, blood flows under low pressure and carry blood away from the heart to various organs of the body 

(c) They have thick elastic walls, blood flows under low pressure; carry blood from the heart to various organs of the body 

(d) They have thick elastic walls without valves inside, blood flows under high pressure and carry blood away from the heart to different parts of the body.

Oxygen liberated during photosynthesis comes from 

(a) water 

(b) chlorophyll 

(c) carbon dioxide 

(d) glucose