Answer:
The process of a star changing overtime.
Socratic can help! This learning app, powered by Google AI, helps you understand your school work at a high school and university level. Ask Socratic a question and the app will find the best online resources for you to learn the concepts.
Thank you!
Please give me a brainliest,
Olvin Otero
Answer:
Those capillaries that have endothelial cells tightly attached have an increase in cell-to-cell junctions, such as desmosomal junctions that are poorly permeable to substances.
These capillaries generally function as conductors or collectors and not as permeabilizers like the pulmonary capillaries that are fenestrated and allow a high passage of substances and gases.
The capillaries are waterproof and prevent the passage of substances or fluids such as in the blood-brain barrier that is very selective
Explanation:
The blood-brain barrier is too selective since it is not favorable for the organism that many fluids, drugs, substances or chemical compounds enter the brain space.
This is the reason why the vessels are waterproof and why pharmacology was challenged to invent drugs that could cross this barrier since it was considered impossible.
An example is dopamine, which in parkynson's disease the levo group is added to dopamine, thus forming levodopamine as a product, this is the only way that the drug crosses the blood-brain barrier and can pass the impermeable barrier generated by capillaries with endothelial cells that are close to each other or closely linked
The inside surface area is shaped in a crescent. It consists of a spiral valve which is made up of the small intestine. Although the dogfish shark has a relatively short small intestine compared to other animals, therefore, the spiral valve allows for a more compact form of the small intestine.
Hence, this structure provides maximum surface area over a relatively short distance in order to make the absorption of nutrients efficient achieved from the food, the sharks had from eating different sea animals.
