Answer:
D
Explanation:
Absolute age is defined as the numeric age of fossils.
To identify the absolute age of a fossil, the amount of certain radioactive elements in the rock are measured. When fossils are formed in the rocks, a small amounts of radioactive elements is included in it. The process to identify age of fossil using radioactive elements is known radiometric dating. So, radioactive isotope and its decay product gives absolute age of fossils.
Hence, the correct answer is "D".
Answer:
Stomatal apparatus is a pair of guard cells with or without surrounding subsidiary cells which function as a value to open or close a stomatal pore for gaseous exchange and transpiration. Each stoma is made of two bean-shaped cells called the guard cells.
Explanation:
The synthesis of fatty acids starts with a preparatory step in which acetyl-CoA is mediated from mitochondria to the cytosol. However, it cannot pass through the membrane, so it is transported as citrate, which is cleaved to acetyl CoA and oxaloacetate.
In the cytosol, acetyl CoA is transformed to malonyl CoA, that is, a three carbon compound. Fatty acid synthesis starts with the conduction of acetyl group from acetyl CoA to fatty acid synthase.
Two carbon groups, supplied to malonyl CoA, are supplemented to the developing acyl chain in a series of steps involving condensation, reduction, and dehydration reactions. Elongation of the fatty acid chain ceases at 16 carbon atoms, after seven cycles, as the free free fatty acid is discharged.
Answer:
The correct answer would be C) respiratory system.
Respiratory system is made up of set of organs which help in taking in oxygen and expelling out carbon dioxide from the body.
In humans, it is composed of nose, pharynx, larynx, trachea, bronchi, pair of lungs, and diaphragm.
Alveoli (in lungs) are the site of gaseous exchange where oxygen is exchange with carbon dioxide.
Carbon dioxide is the toxic waste product of cellular respiration. Circulatory system helps in transporting CO₂ from cells to the alveolar site where it is exchanged with oxygen and excreted out as a part of exhaled air.