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Tema [17]
3 years ago
14

1. How many periods are there in the periodic table? *

Biology
1 answer:
jok3333 [9.3K]3 years ago
3 0
The periodic Table has 7 periods and 18 groups. The number of valence electrons in an atom of sulfur is 6, calcium has 2, chlorine has 7 and arsenic has 5. The element that corresponds to the atomic number 10 is Neon, for 18 it is argon, for 36 it is krypton, and for 90 it is thorium. Na and CI belong to the same period, as does H and He. An element found in period 4 would have 4 energy levels. The transition elements are in groups 3-12. Strontium would be more chemically similar to calcium, because they are both in the same family/group. The heaviest noble gas is radon. The heaviest alkaline earth metal is radium.
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Answer: Sterilization.

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Sterilization is the process that kills, or deactivates all forms of life so then a product is considered free of viable microorganisms. This process must be designed, validated and carried out to ensure that it is capable of eliminating the microbial load of the product.

Since sterility cannot be demonstrated without causing the complete destruction of the products, <u>sterility is considered when the probability of a product being contaminated is acceptably remote.</u> A critical product is considered sterile when the probability of a microorganism being present in an active or latent form is equal to or less than 1 in 1,000,000 (sterility safety factor 10^-6).

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Examples of sterilization include physical methods and chemical methods. Physical methods include:

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Answer:

The correct answer would be elongation.

Cell elongation is defined as the lengthening of a cell during differentiation of a cell. It takes place during growth of an organism or during movement in mature plants.

In plants, it is primarily regulated by light and plant hormones like auxin.

Auxin modifies the structure of the cell wall which helps the cell to elongate.


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