The cell membrane is semi-permeable, kind of like a filter to let some molecules in and keep larger molecules out
<span>7 electrons in each outer shell
Group 17
Most reactive
Fluorine, Chlorine, Bromine, Iodine, Astatine
Alkali Metals:
1 electron is each outer shell
Group 1
Also reactive, but not as much as the halogens
Lithium, Sodium, Potassium, Rubidium, Cesium, Francium </span>
The period of Convalescence is the time during which the person regains health and fully recovers.
Explanation:
- Diseases that can spread from one person to other are called infectious disease.
- Disease development is divided into Incubation period, Prodromal period, period of illness, Decline period, and period of Convalescence.
- During incubation period the pathogen enters the host body and starts multiplying itself. But the signs of diseases are unnoticeable.
- Then comes the prodromal period, when the pathogen keeps multiplying itself and some signs of disease are observed but they are not obvious
- After the prodromal period comes the period of illness when the patient exhibits obvious signs of sickness.
- As the period of illness is over the symptoms of disease start to cease and the the number of pathogen decrease in body.This period is the period of decline.
- Finally comes the period of Convalescence when the person returns to his pre-disease state and is completely healthy. (except irreversible damage caused by the disease)
Answer: the cells differentiate