Answer:
if a molecule is too large it cannot pass. also it depends on the concentration of a specific substance inside the cell. similarly, if a molecule is polar it cannot penetrate the phospholipid bilayer.
there are proteins that work as channels and pumps that allow these molecules to pass
Explanation:
1. hair
2. pore
3. oil gland
4. sweat gland
5. hair follicle
6. blood vessels
Answer:
it involves a physical exchange of chromosome segments in the tetrad (3)
Explanation:
def of crossing over
Crossing over is the swapping of genetic material that occurs in the germline
The difference between topsoil and garden soil is an even finer distinction than the difference between soil and dirt, and it has to do with the amount of organic matter, and to a lesser extent, the types of trace minerals and the ratio of clay, sand and silt. Garden soil is a category of topsoil
The new better species can eat all of their food, take up all of their space, and be more physically dominant so that they are not challenged by the disappearing species. the newer species would have to reproduce really fast and be in its ideal habitat in order to do so and dominant the area or at least the food source for both the species
