Answer:
Innate immunity is a nonspecific defense mechanisms that play its role as soon as an antigen appear in the body (it is relatively rapid but nonspecific and because of that it is not always effective)
Explanation:
The barries of innate immunity are:
Skin: At Epidermal surface, its protective aspect are keratinized cells that lives on the surface, known as Langerhans cells.
Skin sweat or secretions: Their specific defense is sweat glands and sebaceous glands, and their protective aspect is low ph and washing action.
Mucosal surfaces: they are at the mucosal epithelium, and their protect aspects are nonkeratinized epithelial cells.
Oral cavity: They defend salivary glands through Lysozyme
The four postulates of the natural selection include.
1. individuals possessing particular traits are have higher likelihood of surviving and reproducing.
2. different individuals in a population have different traits
3.reproductive and survival rate vary with individuals in a given population.
4. some trait differences are inheritable.
Answer:
this is called revolution ( when the sun gives light to the earth it takes a step closer to revolution were season of the year appear )
The three observations that could help an individual in distinguising whether the organism is a fish or not is that it should live under water as fish can't survive without water, another thing is that it should laid eggs when it comes to giving birth because when it does not lay eggs but produces a living organism normally without an egg, it is considered to be a mammal and lastly, the appearance it possess such as having gils or fins.