<span>D.
Winds blowing over a short area create powerful, high, and fast waves. </span>
Answer: B voltage-gated potassium channels
Explanation:#
Tetraethylammonium is a pH- potassium channel blocker.
Therefore, it prevents the escape of potassium ions from the axoplasm, which makes it ( axoplam) positive from the rise in potassium ions concentration , since potassium ion is positive charged and intracellular ion . This initiate repolarization which returns to membrane state potential.
Since it is pH -potassium ion blocker; it does not affect the voltage-gated sodium ion channels, so action potential can occur. But after the sodium gated channels were closed,action potential drops but the concentration of potassium rises because :
1. They are naturally intracellular ions
2. They cannot leave the axoplasm because the channels has been shut. Therefore this stabilizes the membrane potential
A nonfunctional CD4 protein on a helper T cell would result in the helper T cell being unable to interact with a class II MHC-antigen complex
Importance of Class II MHC-Antigen complex
- CD4+ T cell-dependent immunological responses need antigen presentation restricted to MHC class II.
Professional antigen-presenting cells (APCs) perform a range of functions that are essential for the generation of an effective and specific immune response.
- Dendritic cells (DCs) investigate their surroundings and gather foreign antigens, such as those derived from bacteria or viruses, before activating CD4+ and CD8+ T cells to initiate adaptive immune responses against these antigens.
- The thymus' DCs and epithelial cells express (and also capture) a diverse set of self-proteins that contribute to both central and peripheral tolerance.
Recognizing the processes involved in the creation (and stability) of peptide-MHC class II complexes in APCs provides crucial information about T cellular metabolism including both normal and pathological settings.
Hence, the correct answer is option D
Learn more about APC here,
brainly.com/question/13588471
# SPJ4
Answer: B. beta
Explanation:
Sickle cell anemia is a inherited disorder which occur due to mutation of gene responsible for synthesis of hemoglobin protein. Typically the gene which is responsible for synthesis of beta-globin protein which make the beta chains in the hemoglobin is affected by the mutation. As a result of this the red blood cells acquire a shape of sickle rather than round. Pain, cold, stress, dehydration and illness are the symptoms associated with this disorder.
Multicellular
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