They surround and engulf foreign objects and organisms- process called phagocytosis
...The origin of life on Earth is a set of paradoxes. In order for life to have gotten started, there must have been a genetic molecule.. something like DNA or RNA—capable of passing along blueprints for making proteins, the workhorse molecules of life.
Covalent bonds is important in four macromolecules such as proteins (polymers of amino
acids), nucleic acids (polymers of nucleotides), carbohydrates (polymers of
sugars) and lipids (with a variety of modular constituents) because they served
as a basic structure of macromolecules.
In addition, the resulting covalent bond is a result
of sharing a pair of electrons, one from each atom or molecular units.
Answer:
Unipotent stem cells are capable of differentiating into only one mature, terminally differentiated cell type. Spermatagonial stem cells are unipotent and only capable of developing into sperm cells.
