Which of the following statements about the autotrophs is incorrect?
They synthesise carbohydrates from carbon dioxide and water in the presence of sunlight and chlorophyll
They store carbohydrates in the form of starch
They convert carbon dioxide and water into carbohydrates in the absence of sunlight
They constitute the first trophic level in food chains
In which of the following groups of organisms, food material is broken down outside the body and absorbed?
Mushroom, green plants, Amoeba
Yeast, mushroom, bread mould
Paramecium, Amoeba, Cuscuta
Cuscuta, lice, tapeworm
Select the correct statement
Heterotrophs do not synthesise their own food
Heterotrophs utilise solar energy for photosynthesis
Heterotrophs synthesise their own food
Heterotrophs are capable of converting carbon dioxide and water into carbohydrates
Which is the correct sequence of parts in human alimentary canal?
Mouth → stomach → small intestine → oesophagus → large intestine
Mouth → oesophagus → stomach → large intestine → small intestine
Mouth → stomach → oesophagus → small intestine → large intestine
Mouth → oesophagus → stomach → small intestine → large intestine
If salivary amylase is lacking in the saliva, which of the following events in the mouth cavity will be affected?
Proteins breaking down into amino acids
Starch breaking down into sugars
Fats breaking down into fatty acids and glycerol
Absorption of vitamins
The inner lining of stomach is protected by one of the following from hydrochloric acid. Choose the correct one.
Pepsin
Mucus
Salivary amylase
Bile
Which part of alimentary canal receives bile from the liver?
Stomach
Small intestine
Large intestine
Oesophagus
A few drops of iodine solution were added to rice water. The solution turned blue-black in colour. This indicates that rice water contains
complex proteins
simple proteins
fats
starch
In which part of the alimentary canal food is finally digested?
Stomach
Mouth cavity
Large intestine
Small intestine
Choose the function of the pancreatic juice from the following
trypsin digests proteins and lipase digests carbohydrates
trypsin digests emulsified fats and lipase proteins
trypsin and lipase digest fats
trypsin digests proteins and lipase emulsified fats
When air is blown from mouth into a test-tube containing lime water, the lime water turned milky due to the presence of
oxygen
carbon dioxide
nitrogen
water vapour
The correct sequence of anaerobic reactions in yeast is
Glucose cytoplasm, Pyruvate mitochondria, Ethanol + Carbon dioxide
Glucose cytoplasm, Pyruvate cytoplasm, Ethanol + Carbon dioxide
Glucose cytoplasm, Pyruvate mitochondria, Lactic acid
Glucose cytoplasm, Pyruvate cytoplasm, Ethanol + Carbon dioxide
Which of the following is most appropriate for aerobic respiration?
Glucose mitochondria, Pyruvate cytoplasm, CO₂ + H₂O + Energy
Glucose cytoplasm, Pyruvate mitochondria, CO₂ + H₂O + Energy
Glucose cytoplasm, Pyruvate + Energy mitochondria, CO₂ + H₂O
Glucose cytoplasm, Pyruvate + Energy mitochondria, CO₂ + H₂O + Energy
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
(iii) Haemoglobin has greater affinity for carbon dioxide than oxygen
(iv) Alveoli increase surface area for exchange of gases
(i) and (iv)
(ii) and (iii)
(i) and (iii)
(ii) and (iv)
Which is the correct sequence of air passage during inhalation?
Nostrils → larynx → pharynx → trachea → lungs
Nasal passage → trachea → pharynx → larynx → alveoli
larynx → nostrils → pharynx → lungs
Nostrils → pharynx → larynx → trachea → alveoli
During respiration exchange of gases take place in
trachea and larynx
alveoli of lungs
alveoli and throat
throat and larynx
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
(i)
(ii)
(ii) and (iv)
(i) and (iii)
What prevents backflow of blood inside the heart during contraction?
Valves in heart
Thick muscular walls of ventricles
Thin walls of atria
All of the above
Single circulation i.e., blood flows through the heart only once during one cycle of passage through the body, is exhibited by
Labeo, Chameleon, Salamander
Hippocampus, Exocoetus, Anabas
Hyla, Rana, Draco
Whale, Dolphin, Turtle
In which of the following vertebrate group/groups, heart does not pump oxygenated blood to different parts of the body?
Pisces and amphibians
Amphibians and reptiles
Amphibians only
Pisces only
Choose the correct statement that describes arteries.
They have thick elastic walls, blood flows under high pressure; collect blood from different organs and bring it back to the heart
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
They have thick elastic walls, blood flows under low pressure; carry blood from the heart to various organs of the body
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.
The filtration units of kidneys are called
ureter
urethra
neurons
nephrons
Oxygen liberated during photosynthesis comes from
water
chlorophyll
carbon dioxide
glucose
The blood leaving the tissues becomes richer in
carbon dioxide
water
heamoglobin
oxygen
Which of the following is an incorrect statement?
Organisms grow with time
Organisms must repair and maintain their structure
Movement of molecules does not take place among cells
Energy is essential for life processes
The internal (cellular) energy reserve in autotrophs is
glycogen
protein
starch
fatty acid
Which of the following equations is the summary of photosynthesis?
\(6CO_2 + 12H_2O \rightarrow C_6H_{12}O_6 + 6O_2 + 6H_2O\)
\(6CO_2 + H_2O + \text{Sunlight} \rightarrow C_6H_{12}O_6 + O_2 + 6H_2O\)
\(6CO_2 + 12H_2O + \text{Chlorophyll} + \text{Sunlight} \rightarrow C_6H_{12}O_6 + 6O_2 + 6H_2O\)
\(6CO_2 + 12H_2O + \text{Chlorophyll} + \text{Sunlight} \rightarrow C_6H_{12}O_6 + 6CO_2 + 6H_2O\)
Choose the event that does not occur in photosynthesis
Absorption of light energy by chlorophyll
Reduction of carbon dioxide to carbohydrates
Oxidation of carbon to carbon dioxide
Conversion of light energy to chemical energy
The opening and closing of the stomatal pore depends upon
oxygen
temperature
water in guard cells
concentration of CO₂ in stomata
Choose the forms in which most plants absorb nitrogen
(i) Proteins
(ii) Nitrates and Nitrites
(iii) Urea
(iv) Atmospheric nitrogen
(i) and (ii)
(ii) and (iii)
(iii) and (iv)
(i) and (iv)
Which is the first enzyme to mix with food in the digestive tract?
Pepsin
Cellulase
Amylase
Trypsin
Which of the following statement(s) is (are) correct?
(i) Pyruvate can be converted into ethanol and carbon dioxide by yeast
(ii) Fermentation takes place in aerobic bacteria
(iii) Fermentation takes place in mitochondria
(iv) Fermentation is a form of anaerobic respiration
(i) and (iii)
(ii) and (iv)
(i) and (iv)
(ii) and (iii)
Lack of oxygen in muscles often leads to cramps among cricketers. This results due to
conversion of pyruvate to ethanol
conversion of pyruvate to glucose
conversion of glucose to pyruvate
conversion of pyruvate to lactic acid
Choose the correct path of urine in our body
kidney → ureter → urethra → urinary bladder
kidney → urinary bladder → urethra → ureter
kidney → ureters → urinary bladder → urethra
urinary bladder → kidney → ureter → urethra
During deficiency of oxygen in tissues of human beings, pyruvic acid is converted into lactic acid in the
cytoplasm
chloroplast
mitochondria
golgi body