Answer;
Examples of selectively permeable materials or items are;
1. Vacuum filter- it traps dust but allows air through
2. Coffee filter- allows water to pass through, but does not allow the coffee grounds.
3. Colander -used to strain liquid food from foods. it drains water but is not permeable to larger food particles.
Explanation;
Selective permeability means that a material or a substance allows the passage of some molecules or ions and other materials to pass through it, and inhibits the passage of others.
For example a cell membrane is semi-permeable and thus regulates the transport of materials such that some particles pass through while others can not cross. A semi-permeable membrane allows selective movement of materials, it acts like a filter that allows particles to pass or not according to their size, solubility, electrical charge, or other chemical and physical properties.
This is called Forced Speciation
Answer:
a. the pH within the thylakoid is less than that of the stroma
Explanation:
The pH of thylakoid membrane is 8 at normal conditions but it became highly acidic like 4 during photosynthesis. The electron transport chain utilize the energy released by excited electrons to pump the H+ ions to lumen of thylakoid membrane from stroma during light reaction of photosynthesis. The H+ ions are present in both the stroma and thylakoid membranes. These high potential H+ ions are utilized by ATP synthase complex for the production of ATP.
We know that more the H+ ions lesser will be the pH and lumen have the high concentration of H+ ions. While the pH of stroma is normally kept acidic by plants to create a concentration and potential difference of H+ ions for the production of ATP. That why the lumen have lower pH than stroma of chloroplast.
Natural selection affects or changes a population and not only an individual organism because as there are somethings to be changed in a certain organism to adapt to the changes in the environment, all organisms in a certain species will be able to adapt and the changes therefore is collective.
Genetic selection is the process by which certain traits become more prevalent in a species than other traits. These traits seen in organism are due to the genes found on their chromosomes. Figure 1 allies 4 genes are inherited income in various forms. Genes have more than one version or allele.
