CLASS X LIFEPROCESSESS

The chlorophyll in photosynthesis is used for:

• Absorbing light

• Breaking down water molecule

• No function

• Reduction of CO₂

Proteins after digestion are converted into:

• Carbohydrates

• Small globules

• Amino acids

• Starch

Opening and closing of stomatal pores is a function performed by:

• Stomata

• Chlorophyll

• Chloroplast

• Guard cells

Respiratory pigment in human body is:

• . Chlorophyll

• White blood cells

• Blood plasma

• Haemoglobin

Which of the following statements about the autotrophs is incorrect?

• They synthesize 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 chain.s

What prevents backflow of blood inside the heart during contraction?

• Valves in heart

• Thick muscular walls of ventricles

• Thin walls of atria

• All of these

Which of the following statements (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)

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)

Bile juice is secreted by:

• Stomach

• Pancreas

• Small intestine

• Liver

One cell-thick vessels are called_______________.

• Arteries

• Veins

• Capillaries

• Pulmonary artery