Answer:
The process of passage of different molecules, solutes, and liquids, through the phospholipid bilayer in human cells, and really in all animal cells, is highly dependent on a tight coordination between chemical, and thermodynamic balances, that will collaborate in these elements being able to pass, or not pass, through a cell´s membrane, and activate other mechanisms within the cell when their passage is not possible. Unlike what was once believed, that transport proteins were like buses parked at the membrane and waiting to be loaded with molecules to later remove themselves from the membrane and carry their load into the cytoplasm, scientific research has found that this is definitely so, and that transport proteins do not come off the layer to transport molecules. They are permanently anchored to the membrane and through a series of second messenger systems, energy produced by the passage of certain ions like potassium and sodium, and other such processes, these transport proteins become activated, allow the passage of molecules and change them in such a way that they can be taken into the cell in vesicles, or, they will anchor them to second messengers, who will be responsible for carrying the molecule inside.
From the list of words given and the two sentences down below, which are two reasons why the earlier believed models for transport proteins are not correct would be:
1. Integral membrane proteins are embedded stably in the membrane and protrude from one or both side based on their hydrophobic, or hydrophilic, regions. These sides will not switch because of the disbalance that would be created if the two sides had to be switched chemically to allow them to pass to the opposie sides.
2. For protein to traverse a membrane, movement of its hydrophilic regions through the interior of the membrane would be required, which would be highly endergonic and hence thermodynamically improbable.
A.) Veins in the pulmonary circuit carry oxygen-rich blood
red blood cells are used to circulate oxygen through out the body, thus it is true.
They grow and develop all year. this gives them an advantage over other trees.
Answer:
A. We can deduce that microorganisms such as Citrobacter have a classification from which it is possible to establish the most favorable environment for it, since being gram-negative, lactose positive, optional anaerobic, not endospore, it will prefer the environment as humid sites and that contain wastewater and soil as well as the intestine, it can therefore remain in some contaminated food and be transmitted with consumption
B. Given the aforementioned characteristics of Citrobacter, it does not infect all people and prefers those who have deficits in its defense mechanisms, thus it becomes a favorable site for colonization of newborns, who do not have adequate immunity, according to the case. Clinically, the neonate was able to acquire the infection in various ways, although the medical personnel who have manipulated it do not have positive tests, the microorganism can adhere to contaminated surfaces and it will be necessary to take samples of the mother's and neonate's feces, as well as the soil. and the water where the infected was, to subsequently carry out disinfection processes in the areas and avoid new infections.
Explanation:
charles darwin proposed thoery of natural selection.he had collected imnumerable specimens of plant and animals.he published concept survival of fittest. while explaining he says that There is always competition for food.only those organism survive which shows adptations in various reasons. it thoery of natural selection.
There are some objections,
1. natural selection is not only factor responsible for evolution.
2. darwin did not mention uesful and useless modifications.
3. There is no explanation about slow and abrupt changes