Semi permeable means that some things can go in and out of the cell, but some cannot. Permeable means it allows things to pass through it, so semi permeable means only some things pass through.
Invasive species. Native grasses have evolved with the normally-occurring grazing organisms to achieve a level of reproduction which sustains the grasses despite the grazing. An invasive species disrupts this ecological balance that took millions of years to develop by eating the grass at a rate that exceeds the rate for the grass to re-seed itself and maintain its own population. The invasive species easily decimates the grass population.
10kg mass and a 10kg mass at 10km apart
The probability of transmitting both traits to his son is Zero. This is because the son has one X chromosome and one Y chromosome (XX), therefore since the traits are linked to the X chromosomes, it means the son will only be a carrier but will not show the trait phenotypically.
Oogenesis and spermatogenesis both involve the chromosomal-reduction divisions of meiosis,which takes the gametes from the full complement of chromosomes to the Haploid number of chromosomes. Meiosis is the type of cell division that take place in the gamete cells, where diploid cells of the germ lines undergo cell division to yield haploid cells, normally the gametes are made through this process, that is, the ovum through Oogenesis, and the sperm through spermatogenesis. During fertilization the two combines to produce a diploid cell once again that undergoes continuous mitosis to form a zygote.
