<span>Akhil Share.
Nov 29, 2015.
Origin of earth is about 4.6 billion years ago and origin of life took place 3.7 billion years ago in the ocean in Pre-Cambrian era. The first organism to be originated were the archebacteria ( Prokaryotes )</span><span>Nov 29, 2015</span>
Answer:
The leukocytes are the main defenses of our body.
Explanation:
From the mother cell it will be a differentiation, from the mother cell to be a mother cell hematopoietic, this will turn into a lymphatic mother cell until it will be 3 different kinds of lymphocytes, the B, T and NK.
Lymphocyte B is the responsible for the inmune system based in antibodies and antigens, due to specific proteins.
Lymphocytes T, are the ones that come from the mother cell of the bone marrow. They are the responsible for the immunity against some illness like cancer.
Lymphocytes NK (natural killer) are the responsible for killing bad cells (like cancer cells) because they "eat" them in a phagocytosis process.
Answer:
A. 25 °C, 30 °C, 35 °C, 40 °C, 45 °C
Explanation:
Each enzyme has a temperature at which it works best. In humans and many animals, that temperature is around body temperature (37 °C or 98.6 °F). Most enzymes are denatured and work poorly at 40 °C (104 °F).
That automatically eliminates Option B.
I would pick a temperature close to 37 °C (98.6 °F) and temperatures at intervals above and below that.
Option D is wrong because it includes no temperatures above body temperature.
Option C is wrong, because it includes temperatures of 45 °C and 55 °C, at which the enzymes will be denatured.
That leaves Option A as the best answer. It includes only one temperature above 40 °C.
Substitution causes sickle-cell anemia.
