Answer:
<u>Biofilms are</u> defined as complex communities of microorganisms that grow embedded in a self-produced polymeric organic matrix and adhered to a living or inert surface, and that can present a single microbial species or a range of different species
Explanation:
The bacteria that form the biofilm are in what is called sessile form, exhibiting a phenotype different from those of the same cells in unicellular or free form (planktonic form) with respect to the growth rate and gene transcription (Donlan, 2002 ).
<u>
The formation</u> of biofilms is an adaptive strategy of microorganisms, since growth in biofilm offers four important advantages: (I) protects microorganisms from the action of adverse agents, (II) increases the availability of nutrients for their growth, (III) facilitates the use of water, reducing the possibility of dehydration and (IV) enables the transfer of genetic material (DNA). All of these circumstances can increase your survival capabilities. As a consequence, <u>the usual methods of disinfection or the use of antibiotics are often ineffective against biofilm bacteria</u>.
In addition to the risk of contamination, the development of biofilms can interfere with different processes and cause damage to the equipment. In drinking water systems the formation of biofilms can obstruct the pipes reducing their speed and transport capacity causing an increase in energy consumption. The formation of biofilm in heat exchangers and cooling towers can reduce heat transfer and as a consequence its efficiency in the process. The formation of persistent biofilms on metal surfaces can cause corrosion due to acid production by bacteria.
There are two main reasons why cells divide rather than continuing to grow larger and larger. One of the main reason is that the larger cell become more demanding, therefore the large cell will increase load on the machinery of the cell such as DNA. The other reason is that if the cell grow too large it will be difficult for the cell to move for nutrients and discard the waste across the cell membrane. Also the surface area for each cell will also be reduced, which is required for active functionality of a cell.
Since it has 4 protons, it must have an atomic number of 4. (That makes it beryllium.)
Since it has a 4 protons and 5 neutrons, it has a mass number of 9.
Answer:
1/8 (12.5 %)
Explanation:
Cross: IAi X IAIB
F1: 1/4 IAIA 1/4 IAIB 1/4 IAi 1/4 IBi
Phenotypes:
- IAIA and IAi >> type A blood
- IBi >> type B blood
- IAIB >> type AB blood
Phenotypic frequency type A blood: 1/2 (i.e., 1/4 IAIA + 1/4 IAi) >>
Probability to have 3 offspring with type A blood: 1/2 x 1/2 x 1/2 = 1/8
The human ABO blood group is a system consisting of there different alleles: A, B, and O. This system is used in genetics as an example of codominance because both A and B alleles are expressed in heterozygous individuals (i.e., IAIB), whereas only the allele A is expressed in individuals that have A and O alleles (since O allele is recessive to the A and B alleles).
