Answer:
The correct answers would be maintain chromosome number through generations and cause genetic variations by recombination.
In Meiosis a cell divides into four daughter cells all of which have half the number of chromosomes present in a parent cell.
It helps in the formation of gametes in sexually reproducing organisms.
These gametes (one from father and one from mother) fuse together to form a zygote. It re-established the chromosomal number as that of the parent.
In absence of meiosis, the chromosomal number would have doubled after each generation.
In addition, the meiosis also increases the genetic variation among the population with the help of crossing over which occurs during the pachytene stage of prophase I.
During this event, genetic information is exchanged between the non-sister chromatids of the homologous chromosomes. It produces a new combinations of genes that are different from either parent.
Answer:
Fossils of mollusks would be found in lower strata than that of arthropods
Explanation:
Fossils are found in different layers of sedimentary rocks. The fossils of organisms that evolved earlier are found in the lower strata while those evolved later are preserved as fossils in the upper strata. If mollusks evolved before arthropods, fossils of arthropods would be present in upper layers while those of mollusks would be found in deeper layers.
The ozone layer is the answer!
<span>BACTERIA
Gram-positive bacterium used widely for industrial production of fermented dairy products such as milk, cheese, and yogurt-</span><span><span>Lactococcus lactis</span> </span>
Answer: Sterilization.
Explanation:
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).
Agents that kill microorganisms are called microbicides or more commonly called "germicides". If the agent kills bacteria, it is called a bactericide. And if it kills fungi, then it is called a fungicide. It is important to consider than <u>after an exposure of the sterilized object to the air or its surroundings, it will have become contaminated again with microorganisms.</u>
Examples of sterilization include physical methods and chemical methods. Physical methods include:
- Wet heat (in steam autoclave)
- Dry heat (in sterilization oven)
- Radiation (gamma radiatio, electron beam, X-ray, ultraviolet, microwave, white light)
Chemical methods include a variety of chemicals in liquid and vapor form, for example:
- Hydrogen peroxide
- Chlorine dioxide
- Ozone gases
- Ethylene oxide
- Propylene oxide
- Peracetic acid