Answer:
New cells are spontaneously created from existing cells
Explanation:
In the 1830's, three scientists namely: Matthias Schleiden (a botanist), Theodor Schwann (a zoologist) and Rudolf Virchow proposed the Unified cell theory. In this theory, three parts were universally accepted and they are as follows:
1) Cells are the fundamental and basic unit of all life and structure.
2) All living organisms are made up of one or more of these cells.
3) New cells arise from already pre-existing cells.
These three parts are the widely accepted parts of the cell theory. Although, it was once believed that new cells arose from inorganic matter. This theory, called spontaneous generation or abiogenesis was later disapproved.
Therefore, the statement that, "new cells are spontaneously created from existing cells" is not a part of the CELL THEORY.
Answer:
HIV destroys helper T cells
Explanation:
The evading viruses destroys helper T cells or the CD4+ thus the body can no longer stop some infections. The secondary infections also called opportunistic infections are rampant with people who have AIDS. This is because helper T cells help fight against most infections in the body.
Answer:
c) The presence of an ephiphyseal line
Explanation:
The options should be:
a) the presence of osteoblasts
b) the presence of osteons
c) The presence of an ephiphyseal line
d) the presence of hyaline cartilage on the ends of the bone
Explanation:
In vertebrates, the epiphyseal line is formed once the bone is completely grown. This occurs inside a plate known as the epiphyseal plate.
From the age of 18 to 21, the bone stops growing and the cartilage inside this plate gets replaced by bone. However, bones can keep growing in width until we are approximately 25 years old.
Therefore, the physical sign that indicates that a bone cannot continue longitudinal growth would be the presence of an ephiphyseal line.
Answer:
Mercury: It has very little atmosphere
Venus: It barely spins on its axis
Earth: It has an abundance of liquid water
Mars: It has 2 moons.
Explanation:
Answer:
Explanation:
a)Organ transplantation requires that the donor organism and recipient be genetically close so that the graft or transplant will not be attacked by the immune system of the recipient leading to rejection and damage. Squeaky is likely to be made up of a different genetic configuration compared to laboratory inbred FG426 mouse
b) ips (induced pluripotent stem cell) on the other hand can benefit squeaky since the cells are somatic cells such as B cells, Keratinocytes, neuronal progenitors cells, kidney and muscles gotten from the donor that are reprogrammed by reactivating silent genes through fusing of another different cell such as ES (embryonic stem cell) and introduction of some transcriptional factors such oct4, sox2,kf4, and k-myc leading to transcriptional activity and DNA methylation. This induced pluripotent stem cells can be grown into organ that can be transplanted to the recipient who was initially the donor of the reprogrammed somatic cells. Because it is from the host, the transplanted organ is not likely to trigger immune response compare to those grown from ES from other bred.