Answer:1) it protects the nucleic acid from digestion by enzymes, 2) contains special sites on its surface that allow the virion to attach to a host cell, and 3) provides proteins that enable the virion to penetrate the host cell membrane and, in some cases, to inject the infectious nucleic
Explanation:
Answer:
RBCs' production is controlled by erythropoietin.
Mature RBCs are released into the bloodstream after approximately seven days RBCs are produced in the bone marrow
Explanation:
The hormone erythropoietin is produced and released in the bloodstream by peritubular interstitial cells of kidneys. The function of erythropoietin is to increase the number of the precursors of red blood cells and thereby to stimulate the production of red blood cells in the bone marrow. When the oxygen supply to body cells is reduced, the hormone erythropoietin stimulates the development of proerythroblasts into reticulocytes and thereby increases the RBC production.
RBCs are produced by the process of erythropoiesis and take about seven days to become mature and to be released in circulation to serve the function of oxygen delivery. The maturation of RBCs also includes the loss of most of the organelles such as the nucleus and mitochondria to accommodate hemoglobin protein. The life span of circulating RBCs is about 100-120 days.
The question is incomplete. The complete question is:
Plasmodesmata are cell junctions that are found between ________.
a) adjacent animal cells in the same tissue type
b) individual cardiac cells in heart muscle tissue
c) the plasma membrane of actively dividing prokaryotes
d) adjacent plant cells
Answer:
d) adjacent plant cells
Explanation:
Plasmodesmata are the cytoplasmic channels that connect the adjacent plant cells together and maintain the continuity of their cytoplasm. These are the narrow channels with 20-40 nm diameter. Plasmodesmata serve the function analogous to the gap junctions of the animal cells. The presence of plasmodesmata between the neighboring plant cells allows the movement of molecules and ions between them. Plant cells can adjust the diameter of the plasmodesmata according to the requirement to allow the transport of substances across them.
Answer:
Enzymes are specialized proteins that soil microbes use to make nutrients available for microbial and plant uptake, by breaking down organic material into small enough molecules for plants to absorb through their cell wall
Explanation:
The finches of the same genus had different characteristic on the different islands of the Galapagos. They had different graded beaks sizes and shapes. In some islands, finches had sharp beaks for stabbing their prey. In other islands, the fiches had short stout beaks for grain-eating. This is a case of allopatric speciation where a population of the finches diverged to.adapt to the habitats in the different islands and also claim different niches
