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3 years ago

Who is a physician who specializes in diagnosing and treating diseases and injuries of the eye?

1 answer:

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Ophthalmology is the specialty dealing with disorders and injuries of the eye... And ophthalmologist is the specialist responsible. Do not confuse with a optometrist. An optometrist only does basic diagnosis and fitting for eye ware.

You might be interested in

1. What is the total magnification of an object if the ocular lens magnification is 20x and the objective lens magnification is

V125BC [204]

1. Answer: 900x

A typical microscope has two lens: ocular lens which located near the eye, and objective lens which located near the object. The image will undergo magnification of both lens. The total magnification of the object would be the product of both lens multiplication, not the sum. The multiplication will be: 20x * 45x= 900x

total mag= ocular * object

total mag= 20x * 45x

total mag= 900x

2. Answer: 100x

The total magnification of the object would be the product of both lens multiplication. If the total magnification 1000x, that mean it was the product of ocular lens and objective lens. If ocular lens magnification is 10x, objective lens magnification would be:

total mag= ocular * object

1000x= 10x*object

object=1000x/ 10x=

object=100x

3. Answer: 0.2 mm

The area of the microscope that can be viewed by the eye should be the same. But since the magnification is different, the actual area that it represent will be different. Microscope with bigger magnification will have smaller diameter of the field of view(DFV). Remember that micrometer(μm) is 1/1000 of millimeter(mm). The DFV would be:500 μm/ ( 1000x/400x)= 200μm= 0.2 mm

4. Answer: 750μm

This question is similar to number 3 question. Remember that 1 millimeter(mm) equal to 1000 micrometer(μm) .

The DFV of a 10x objective lens is 3 mm. Then the DFV of 40x lens would be:

DFV2= DFV1/ (mag1/mag2)

DFV2= 3mm/ ( 40x/10x)= 0.75 mm= 750μm

5. Answer: 125μm x 37.5μm

The lens DFV of microscope from question 4 is 750μm, so the width and length of the area would be 750μm.

If 6 organisms could fit across the DFV if they were laid end-to-end, the length would be: 750μm/ 6 organism= 125μm

If 20 organism could fit is stacked side by-side, then the width would be: 750μm/ 20 organism= 37.5μm

6. Answer: 6mm

This question is similar to number 3 and number 4 question. Remember that 1 millimeter(mm) equal to 1000 micrometer(μm).

The DFV of a 100x objective lens is 1.5 mm. Then the DFV of 25x lens would be:

DFV2= DFV1/ (mag1/mag2)

DFV2= 1.5mm/ (100x/25x)= 6 mm

7.Using the 100x objective lens from question 6, you estimate 12 organisms could fit across the DFV if they were laid end-to-end and 30 could fit is stacked side-by-side. What is the length and width of this organism (in microns)?

Answer: 0.5mm x 0.2mm or 500μm x 200μm

The lens DFV of microscope from question 6 is 6 mm, so the width and length of the area would be 6 mm.

If 12 organisms could fit across the DFV if they were laid end-to-end, the length would be: 6mm/ 12 organism=0.5mm

If 30 organism could fit is stacked side by-side, then the width would be: 6mm/ 30 organism= 0.2mm

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3 years ago

Proteins are important food nutrients. A technician working at a food company is interested in the nutritional content of seeds/

Vladimir79 [104]

Answer: Sample 1 then, has more variety of proteins but less quantity of each one, while sample 2 has less variety but more quantity of the two proteins present.

Explanation:

Proteins are molecules found in the cells of all living organisms. A protein is composed of monomers called amino acids linked together by peptide bonds. To analyze proteins, a technique called SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) is used. This technique is used to separate proteins according to their electrophoretic mobility, depending on polypeptide chain length, molecular mass, post-translational modifications and other factors. SDS (sodium dodecylsulfate) is an anionic surfactant compound that breaks non-covalent bonds in proteins, denatures them causing these protein molecules to lose their native conformation and provides the polypeptide with a negative charge that is proportional to the chain length (the number of amino acids) and, therefore, to the molecular mass of the protein. The electrostatic repulsion created by the binding of SDS to the protein is one of the causes of the protein losing its native conformation, thus eliminating the differences in conformation of the different proteins to be separated in the gel.

An electric current is applied to the gel where the proteins are seeded, causing the negatively charged proteins to migrate through the gel in the direction of the anode (positively charged region). Short proteins will move more easily and faster through the pores of the gel, while larger proteins will find it more difficult to do so. After a certain time, the proteins will have migrated according to their size (measured in kDa or kiloDaltons). After electrophoresis, the gel should be stained with Coomassie blue or silver stain, allowing visualization of the separated proteins. After staining, the different proteins will appear as distinct bands on the gel. In addition, the higher the amount of a protein, the more intense the color of its band will be.

Extract No. 1 shows three bands: 25, 30 and 35 kDa. This means that it has three different proteins, each with a different molecular weight. Extract number 2 shows two bands: 25 and 35 kDa. It means that this sample has only 2 proteins. And being bands of higher intensity, we can say that there is more of each protein.

Sample 1 then, has more variety of proteins but less quantity of each one, while sample 2 has less variety but more quantity of the two proteins present.

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2 years ago

What is one difference between dna and rna?

OleMash [197]

D
Cos Dna contains deoxyribose, Rna ribose

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3 years ago

How do we get Proteins

Leona [35]

Answer:

By eating things with protein in it. Sorry if this sounds too simple, but that's all it is.

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