Answer:
The skeletal system is vital in supporting the immune system because : Bones contain marrow, a porous material which creates both white and red blood cells. This replenishment of cells allows the body to fight and expel harmful bacteria, environmental toxins, foreign material e.t.c.
The white blood cells formed by the marrow are instrumental in isolating and destroying harmful particles (either on the site or in lymph nodes), or transporting them to the kidneys or bowels for excretion.
NOTE : Some people have marrow disorders which prevent their marrow from forming new cells; this is caused most often by cancer. Today, it is possible to transplant marrow from a healthy individual to a sick patient, and so help their bone marrow form new white and red blood cells to fight their sickness.
I hope it helps :)
<span>The Answer is B: They could use the Benedict's test; it would not have a positive reaction for sucrose but it would for the other three sugars.</span>
Microorganisms can be divided into two groups:
1. Archea
• Archea are prokaryotic unicellular organisms without cell nucleus or other membrane bound-organelles.
• Their membrane is built from ether lipids, which differs them from bacteria’s cell membrane.
•
2. Bacteria
• Bacteria are also unicellular prokaryotic organisms.
• Bacterial cell membranes are made from phosphoglycerides with ester bonds. Bacterial genome is in a form of circular chromosome.
• They reproduce by binary fission or by budding.
Besides, prokaryotes (Archea and Bacteria) a large number of eukaryotes are also microorganisms. Unicellular eukaryotes contain organelles such as the cell nucleus, the Golgi apparatus and mitochondria. Usually, they reproduce asexually by mitosis. An example of eukaryotic microorganism is Protist.
The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period.
