The vein which brings clean blood from the lungs into the heart is known as:
The pulmonary vein is responsible for bringing oxygenated and pure blood into the heart.
The opening and closing of the stomatal pore depends upon
When a pair of guard cells surrounding a stoma receives the signal to open the stomatal pore, it is filled with water, thus changing the cell's shape and opening the pore. When guard cells receive a signal to close the stoma. This initiates a loss of water and causes them to shrink and the pore closes. Thus, the correct answer is option C.
Movement of food through the oesophagus is due to :
Peristalsis is the rhythmic contraction and relaxation of muscles of the alimentary canal that propels the food in downward direction.
Oxygen liberated during photosynthesis comes from
Photosynthetic oxygen evolution occurs via the light-dependent oxidation of water. Green plants utilize the light energy to split the water molecule to protons and electrons for photosynthesis. Free oxygen is generated as a by-product of this reaction and is released into the atmosphere.
So, the correct answer is option A.
Sometimes we get painful cramps in our leg muscles after running for a long time due to the accumulation of:
During heavy exercise, the demand for energy is high but the supply of oxygen to produce energy is limited. Therefore, anaerobic respiration takes places in the muscles cells to fulfil the demand for energy. This anaerobic breakdown of glucose leads to the formation of lactic acid in muscles. The accumulation of lactic acid in muscles leads to muscle cramps. Hence, during heavy exercise, we get cramps in the legs due to the accumulation of Lactic acid.So, the correct answer is 'Lactic acid'.
The filtration units of kidneys are called
Nephrons are the basic filtering units of a kidney each kidney poses a large number of nephron approximately 1-1.5 million the main components of a nephron are- glamorous ,women's capsule, a long renal tubule and collecting duct-
Functioning of a nephron - The blood enters the kidney through a long ranal tubal which branches into many capillaries associated with the glamorous.
The main functions of a nephron are:
The common step between aerobic and anaerobic respiration takes place in :
When air is blown from mouth into a test-tube containing lime water, the lime water turns milky due to the presence of
The air we exhale contains CO2. When carbon dioxide is passed through lime water or Ca(OH)2 then it form calcium carbonate which is white in colour.
Which is the first enzyme to mix with food in the digestive tract ?
Salivary amylase, present in saliva, is the first digestive enzyme that gets mixed with food in the oral cavity during the process of mastication and bolus formation. The digestive enzyme salivary amylase hydrolyzes starch into maltose, malto-triose, dextrin and a small amount of glucose.
Which part of alimentary canal receives bile from the liver ?
The small intestine is made up of duodenum, jejunum, and ileum. It receives the bile from the liver which helps in the breakdown of fats.