Answer:a. A cataract is a clouding of the lens. Some cataracts are congenital, but most are due to age-related hardening and thickening of the lens, diabetes mellitus, or exposure to UV rays over time. The lens can be removed and replaced
with an artificial lens.
Explanation:
<span>While Acid fast bacteria retain carbol fuchsin after acid-alcohol treatment, non- Acid fast bacteria are decolorized by acid-alcohol.
Bacteria of genus mycobacterium are best stained using acid-fast method. A mixture of Phenol and fuchsin is carbol fuchsin. In acid-slcohol, acid is hydrochloric acid.</span>
Answer: Clathrin cages assemble, vesicles form but cannot be pinched of but no disassembly occurs so the vesicles remain coated in clathrin.
Explanation:
Endocytosis is a cellular mechanism that allows the introduction of extracellular material into the cell. Clathrin-coated vesicles act to incorporate different molecules that are recognized by specific proteins located in the clathrin-coated pits. Upon invagination of a portion of the plasma membrane, the material is transported to its final intracellular destination.
<u>Clathrin is a protein that forms the lining of cell membrane microcavities where various receptors are located. Once a particle is recognized by the receptors, invagination of the plasma membrane occurs, which then fuses to form an endocellular vesicle.</u> When vesicle budding occurs, the vesicle is detached from its attachment to the membrane with the help of a GTPase protein called dynamin. Then, the vesicle is freed from clathrin by the action of a type of ATP-ase called Hsp70-ATP and docks to late endosomes that are immediate precursors of lysosomes, fusing the membranes of both. The fission of the clathrin-coated vesicle is controlled by the GTPase dynamin and it has been proposed that dynamin acts by generating the necessary force to strangle the "neck" and cleave the vesicles from the membrane. So they are mainly involved in the cleavage of newly formed vesicles from the membrane of one cell compartment, their orientation, and their fusion with another compartment. Also, without the dynamin, vesicles are not freed from clathrin.
<u>In the absence of dynamin, vesicles are formed but the membrane fusion or pinching off will not occur. Then, invaginated coated pits will be found.</u>
Answer: Fluorescence microscope
Explanation:
The basic function of a fluorescence microscope is to irradiate the specimen with a desired and specific band of wavelengths. A fluorescence microscope uses a mercury or xenon lamp to produce ultraviolet light. The light comes into the microscope and hits a dichroic mirror. The dichroic mirror reflects the ultraviolet light up to the specimen. The ultraviolet light excites fluorescence within molecules in the specimen. The objective lens collects the fluorescent-wavelength light produced. This fluorescent light passes through the dichroic mirror and a barrier filter, making it to the eyepiece to form the image.
