Answer: cell membrane
such as water, micro-organism
physical process
simple diffusion, osmosis and filtration
such as potasssium permaganate in water,urea a liver waste diffuses from the body and the kidney help in filtering it out
physiological processs
active transport, phagocytosis and pinocytosis
such as soduim-potassium pump, exocytosis
Explanation: transportation in and out of cell is done in different ways listed above but a barrier to this movement is the cell membrane which is an outer covering of the cell. it protect the cell and only some materials can penetrate the cell membrane e.g micro-organism, water e.t.c. the various physical and physiological processes are the various ways substance cna be liquid, solid or gas are transported within or outside the cell e.g food
1c. More
2d. In
2a. Inward
2b. Upward
2c. Less
2d. Out of ( not so sure though try searching on google maybe )
Anyways I hope this was helpful
<span>By the late 1960s, scientists had developed the theory of plate tectonics based on a range of new evidence. Technological advances had helped reveal that the ocean floor was not essentially flat, as once assumed, but instead was marked by 50,000-kilometer-long (31,000-mile), 3,000-meter-high (9,800-ft) ridges and 11-kilometer-deep (7-mile) trenches. Scientists found striking patterns related to these features. They found that the youngest oceanic crust is located nearest the mid-ocean ridge and the oldest crust is nearest the trenches. They also detected a pattern of alternating magnetic polarity along the ocean floor, which emanated from the ridge tops. These two pieces of evidence, coupled with the fact that volcanic activity and island-building occurred most commonly at ocean trenches, suggested that new crust was created at mid-ocean ridges and destroyed at ocean trenches. Scientists Harry Hess and Robert Dietz used this evidence to revive and expand Holmes' convection theory into the theory they called "seafloor spreading." Finally, Wegener's notion of continental drift was coupled with a mechanism that could explain the movement of tectonic plates.</span>
A polar molecule has a net dipole because of opposing charges. Nonpolar molecules share/give electrons . If the electrons are shared equally, the molecule is nonpolar, because there is no charge. I hope this helped ^^
The air that we breathe is mostly made up of nitrogen (78%). 21% is oxygen which is needed for animals and humans in respiration and 0.03% is carbon dioxide which is needed for plants to make energy in a process called photosynthesis. The bit that is left is made up of rare gases like helium and argon and methane.
