Answer:Small hydrophobic molecules and gases like oxygen and carbon dioxide cross membranes rapidly. Small polar molecules, such as water and ethanol, can also pass through membranes, but they do so more slowly.Semipermeable membranes, also termed selectively permeable membranes or partially permeable membranes, allow certain molecules or ions to pass through by diffusion.
Explanation: hope that helps
Fundamental niche is the job/role that one species can have in the environment .
The realized niche is the role of a species influenced by several factors in the environment.
Example:
The fundamental niche of Yellow Warblers is found in a spruce tree.
The realized niche of the Yellow warblers is when they are "forced" to share the spruce tree and remain in one particular area of the tree while other warbler species play defense different niches in other parts of the tree.
:v it is like :
•Fundamental niche: [yellow warbler] "I got my home, all for me..."
~new species arrive to the spruce tree~
•Realized niche: [yellow warbler] oh, shoot! I gotta stay in the upper part/move to the upper part as the others warbler "struggle" to get territory :v or they just choose their own . :v
In multicellular plants and animals, however, meiosis is restricted to the germ cells, where it is key to sexual reproduction. Whereas somatic cells undergo mitosis to proliferate, the germ cells undergo meiosis to produce haploid gametes (the sperm and the egg).
