Because it is meant to be like that for animals , us humans dont need all the stuff that animals do.
Answer:
The two factors are:
• The kind/type of surface involved.
• The force that the surface are being pushed together.
Explanation:
Friction can be said to be the general term used to describe the force that one surface exert on another when they rub against each other.
When the surface is partially not smooth or totally rough, a greater force is been needed to move one surface past the other.
The weight of the can also significantly be a key factor. This is where the need to friction reduction come to play a role; and need for friction reducers like lubricant, rollers etc helps.
Answer: False
Explanation: The COMPLEMENT SYSTEM consists of proteins synthesized in the liver. They are activated by inespecific harmful substance (antigen) and begins a cascade of proteins that finally forms an attack complex against bacteria.
The COMPLEMENT is part of the INNATE IMMUNITY, because it is an inherent response, something all humans born with, and it is part of the first defense barrier against any antigen. Part of the innate immunity are too: natural killer cells, neutrophils, monocytes, dendritic cells and macrophages.
On the other hand, the ADAPTATIVE IMMUNITY, is the response that the body develops after being exposed to an antigen before. It is like something that the body recognizes, and then "learns" how to act against it. Part of the adaptative immunity are: lymphocyte T and B, and the antibodies (substances called Immunoglobulins). The immunoglobulins (Ig) are glycoproteins present in the blood.
Answer:
D
Explanation:
I am working on that kind of stuff right now
Cell membranes help organisms maintain homeostasis by controlling what substances may enter or leave cells
