Answer:
Explanation:
In a cross-section of an adult tree trunk, the outer layer that interacts with the environment is called periderm (Layer D). The second layer that follows the periderm is the phloem (Layer C). The next layer is the cambium, which produces phloem cells and xylem cells (Layer B). The secondary xylem follows the vascular cambium (Layer A) and finally, the medulla is located in the middle of the trunk.
The secondary xylem proceeds from the vascular cambium activity. Its cells are orientated in different ways composing the vertical/axial system and the horizontal/transversal system. The secondary xylem is essential to the tree growth in high because of its resistance and the capacity to transport water long distances. Secondary xylem functions are to transport water and minerals through its vessels and tracheids, to provide support and resistance to the plant, and to store reserve substances.
The lactic acid that is building up in his muscles will eventually cause him to stop exercising. The burning sensation comes from the build up of that lactic acid in his muscles.
At high altitude, atmosphrric pressure is very high;
the partial pressures of ocygen are considerably lower,
the inhabitants must have a higher concentration of haemoglobin to increase surface area for carrying more oxygen
Nucleic acid monomers are nucleotide and are made up of a phosphate group, a five carbon sugar (either deoxyribose for DNA or ribose for RNA), and a nitrogenous base (either adenine, guanine, cytosine, thymine, or uracil)
