Phylogenetic trees are often used to track what evolved from what.
The hemoglobin holoenzyme (active enzyme) is a complex of an iron ion and 4 subunits- 2 hemoglobin alpha and two hemoglobin beta. People with sickle cell disease have mutated beta hemoglobins. The mutation is a single nucleotide exchange, that changes the 6th amino acid of protein primary struture - a Glutamic acid into Valine. This one alteration changes the tree dimentional structure of hemoglobin beta so, that it forms lond fibres that disrupt the normal circular form of the red blood cells.
Answer:
e.) If exposure to cowpox gives immunity to smallpox in milkmaids, then milkmaids have a natural immunity and their blood should be used to develop a smallpox vaccine.
Explanation:
- Milkmaids who suffered from cowpox did not suffer from smallpox i.e. they were immune to the disease.
- If milkmaids did not suffer from smallpox then there must be some element of immunity that they received once they had recovered from cowpox, this would likely be found in their blood as antibodies.
In order for plants to make their own food, they must go through a process called photosynthesis. This process occurs in the chloroplasts of a cell. To begin this process, all items needed must go to the cells of a plant. Water and nutrient are absorbed from the soil through the roots. A tube called the xylem carries only water up the stem to the rest of the plant. Gas exchange in the plants occur in the tiny pores of a leaf called the stomata. This is opened and closed by the guard cells. The food produced by this process is called ATP and it is a macromolecule known as a nucleic acid.
