<span>The toxin Bt (endotoxin
CrylA (b)) Bacillus thuringiensis that
is a normal inhabitant of the soil, showed himself as a natural insecticide
used by farmers engaged in organic farming. In contrast to the Bt-toxin
produced by bacteria, genetic engineers included it pesticide in every cell of
the seed, and therefore distributed throughout the adult plant, the products
from which then are consumed by man. </span>That's why scientists are concerned that after the use of a BT toxin
products people get antibiotic resistance and resistance to bt.
Answer:
a. Oxygen performs an essential role in the mentioned microbial cell in a manner that it takes part in the procedure of glycolysis, Krebs cycle, and electron transport chain, which eventually assists in the production of energy from food substrates and this generation of energy helps the cell to survive.
In the existence of oxygen, sugar gets dissociated through glycolysis to generate pyruvate, which again in the existence of oxygen is transformed into acetyl CoA. This moves into the Krebs cycle and gets dissociated to water and carbon dioxide generating ATP through ETC. This generation of ATP helps the cell to survive.
In low oxygen surrounding or in the absence of oxygen, some of the aerobic microbes can switch their respiratory pathway and carry on the process of fermentation and anaerobic respiration to produce energy and thrive. However, the mentioned microbial cell, which when it comes in contact with the low oxygen environment cannot carry out fermentation process and would die eventually.
b. This organism can be classified as obligate aerobes as they always need oxygen and do not possess the tendency to carry out the process of anaerobic respiration or fermentation under the absence of oxygenic environment.
Answer:
The question lacks options, the options are:
A) 1 out of 16
B) 3 out of 16
C) 6 out of 16
D) 9 out of 16
The answer is 1 out of 16
Explanation:
This is a DIHYBRID cross because it involves two different genes coding for distinct traits. One of the traits will be dominant while the other recessive. Hence, parents that are purebred for opposite forms of the trait means that one parent is homozygous dominant while the other is homozygous recessive. When these two parents cross, they produce F1 offsprings that all possess the dominant trait but heterozygous/hybrids.
When these hybrids are self-crossed, they produce four different combinations of gametes which when crossed using a punnet square will result in F2 offsprings with a 9:3:3:1 phenotypic ratio according to Mendel's observation.
9 represents offsprings that are dominant for both traits
The two 3's represents offsprings that are recessive for one trait and dominant for the other respectively.
1 represents offsprings that are homozygous recessive for both traits.
Hence, 1 out of 16 offsprings will be homozygous recessive for both traits.
Complete question:
The endplate potential (EPP) at the frog neuromuscular junction occurs because ACh simultaneously increases the conductance of the postsynaptic membrane to Na and K
Answer:
TRUE
Explanation:
The Acetylcholine neurotransmitter is released from the presynaptic cell by the process of exocytosis.
Once the molecule is in the intercellular space, it moves forward the postsynaptic membrane to join its receptor in the motor plate.
Once the joining has occurred, the receptor acquires a channel shape allowing the ion transference that will make possible the modification of the action potential. Ions traffic will consist of the pass of sodium and calcium to the interior of the cell and potassium to the exterior. Quantitatively, the interchange Na-K is the most significant.
K+ follows a concentration gradient, while Na+ follows an electrochemical gradient. The interchange results in an increase of positive charges in the interior of the muscular cell.
Whenever there is a sufficient number of Acetylcholine receptors are active, the depolarization threshold of the motor endplate is exceeded. This activates an action potential that extends to the rest of the muscle membrane.
