All living organisms reproduce i.e. replicate themselves by producing young ones. However, they either do this sexually or asexually. Asexual reproduction involves the contribution of only one of the parent while sexual reproduction involves the two parent's contribution.
In sexual reproduction, a process of gamete formation called MEIOSIS occurs whereby the parental cell produces reproductive daughter cells that have a reduced number of chromosome (by half). The male and female gamete unites in sexual-reproducing organisms to form the offsprings.
Since only one parent is needed in asexual reproduction, there is no need for formation of gametes, hence, meiosis (a division only for reproductive cells) does not occur. The parent simply divides into its progeny.
The cell membrane is said to be selectively permeable is because it allows a select few things to go through while stopping the passage of other stuff.
A white blood cell engulfing foreign materials is more likely to carry out Endocytosis.
Explanation:
Endocytosis is the process by which a cell takes up a macromolecule into is cytoplasm by forming a vessicle.
In the question two cases are given, both the cases involve the formation of membrane bound vessicle but in different ways.
The excretion of hormones involves the movement of molecule outside the cytoplasm. This process is exocytosis.
The engulfment of an antigen by WBC involves taking up of molecule within the cell so that it can be killed and digested. Thus in this case Endocytosis is more likely to occur..
