Answer:
A
Explanation:
The sun is what drives most processes, the sun gives energy to the plants which help them grow resulting in creatures consuming the plants. The sun is the major source so remeber that! :D
I am sure this is the answer so I hope this helps you!
Proteins for sure because lipids don't have enough antigen
What is the primary cellular site for the production of polypeptide chains? Ribosomes
Portals of entry are the sites where micro-organisms can enter a host and reproduce, causing diseases or infections. There are various portals of entry in the human body. This can include the skin, our mucous membranes, and even our respiratory and gastrointestinal tracts. Portals of exit are where these micro-organisms leave and spread to other individuals. Portals of exit include coughing, sneezing, and some of our bodily fluids.
The pluripotent, undifferentiated cells in the bone marrow that give rise to the formed elements are called stem cells.
Pluripotent stem cells have the ability to undergo self-renewal and to give rise to all cells of the tissues of the body. However, this definition has been recently complicated by the existence of distinct cellular states that display these features.
There are two types of pluripotent stem cells :
- Embryonic stem cells (ESCs)
- Induced pluripotent stem cells
Embryonic stem cells are derived from the inner cell mass (ICM) of pre-implantation embryos and can be indefinitely maintained and expanded in the pluripotent state in vitro. Pluripotent stem cells can also be obtained by inducing dedifferentiation of adult somatic cells through a recently developed in vitro technology, known as cell reprogramming.
Similarly to Embryonic stem cells , Induced pluripotent stem cells can be expanded indefinitely and they are capable to differentiate in all the derivatives of the three germ layers.
Another intriguing features of being pluripotent is its reliance on gene expression heterogeneity.
Learn more about Pluripotent here : brainly.com/question/18243320
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