Is there a picture to go with this?
I believe the biggest space mission of the twenty-first century will be a manned mission to Mars, and the colonization that follows. This is the stated goal of several nations, companies, and individuals, all with considerably deep pockets. This mission will not only be a huge leap forward in space exploration, it will usher in a new era in human history in which the human race is an interplanetary civilization, a natural milestone as humanity continues to progress and advance.
Significant challenges are many and overwhelming. In terms of getting to mars, we need efficient, powerful propulsion systems and a spaceship that can not only accommodate a full crew for a mission that would likely last years, but withstand the various hazards that a long trip through space and entrance into the Martian atmosphere will entail. In terms of colonization, significant challenges will include establishing efficient and frequent travel/transport between the planets, and in the longer term, the necessity to terraform the planet (make it more like Earth) so that humans can more easily live there.
Tissue(interstitial)fluid
Answer:
Organisms are part of an environment and are continually adapting to the changes to live. These environmental changes and the adaptation play a major role in evolution of organism.
Explanation:
A sacromere is a segment between two adjacent Z discs and are essential for the striated structure of the cardiac and skeletal muscles.
<u>Explanation:</u>
The Z disc is surrounded by the I band made of thin filament called actin. The I band is followed by the A band made up of thick filament called myosin. When the muscles contract the actin and the myosin become superimposed/overlapped.
The sliding filament model explains the contraction of the sacromere in which the Z discs move closer due to the overlapping of the thin and thick filaments. Thus the I band moves close to the A band which remain the same length as shown in figure.