Explanation

Meissner corpuscles provide sensation about touch, while Pacinian corpuscles provide sensation about pressure.

Meissner corpuscles are found in the dermal papillae of the skin and are sensitive to light touch and vibration.

They are particularly concentrated in areas such as the fingertips, lips, and palms.

Pacinian corpuscles are found deeper in the skin and are sensitive to deep pressure and high-frequency vibration.

They are responsible for detecting mechanical stimuli such as pressure and vibration.

Explanation

Annelids do have a closed circulatory system, along with other invertebrates and vertebrates

Annelids, like earthworms, have a closed circulatory system.

In annelids, blood is pumped along by muscles in blood vessels.

The blood picks up food molecules from the digestive tract and oxygen from the skin.

It then transports these to the cells of the body. 

Explanation

• The revolution of the Earth around the Sun causes the changing seasons, including Summer and Winter.
• As the Earth's axis is tilted and different parts of the planet receive varying amounts of sunlight throughout the year.

Explanation

The correct amount of CO2 in 100 ml of venous blood is 51 ml.

Venous blood carries carbon dioxide (CO2) back to the heart and lungs after it has circulated through the body.

The normal range of CO2 content in venous blood is typically around 51 ml per 100 ml of blood. 

Explanation

• The Earth's axis is an imaginary line that runs through the North Pole and the South Pole, around which the Earth rotates.
• It is an imaginary reference point, not a physical object or shape.

Explanation

• The Earth completes a day in a Solar day, which is approximately 24 hours.
• This is the time it takes the Earth to rotate once on its axis, causing day and night to cycle.

Explanation

Instead of alveoli, birds (aves) have parabronchi.

Parabronchi are the structures in the avian respiratory system

They are the site of gas exchange, where oxygen from the air is absorbed into the bloodstream and carbon dioxide is released from the bloodstream into the air.

Birds have a unique respiratory system that includes air sacs connected to their lungs. 

Parabronchi are the functional units where gas exchange occurs within the avian respiratory system.

Explanation

• The Earth rotates on its axis, completing one full rotation in 24 hours.
• This is the equivalent of 1,440 minutes or 86,400 seconds.
• This rotation is what gives us day and night, as different parts of the planet face towards or away from the Sun.

Explanation

Enterokinase, also known as enteropeptidase, is an enzyme produced by cells lining the duodenum in the small intestine.

It plays a crucial role in the digestion of proteins by activating trypsinogen, an inactive precursor of trypsin.

Once trypsinogen is activated by enterokinase,

it can then activate other pancreatic zymogens and initiate the digestion of proteins in the small intestine.

Explanation

• The rotation of the Earth on its axis causes day and night.
• As different parts of the planet face towards or away from the Sun.