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Can someone please help me with these questions? I put them on here and some keep getting taken down. I need help asap!

Answer the following questions in complete sentences.

Why do you think that you had to use a thin layer of onion skin, rather than a thick layer for the microscope?
When iodine reacts with starch, it produces a blue-black color. Starch is a white substance which plants use to store food. What structure did you see better because of the iodine? Why did you see this structure better?
From low power to high power, what structures became clearer in the unstained onion tissue?
From low power to high power, what structures became clearer in the stained onion tissue?
What is the shape of an onion cell?

User DrewB
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1 Answer

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Ques.1: Why do you think that you had to use a thin layer of onion skin, rather than a thick layer for the microscope?

Ans:- It is because, I the onion peel is thick layered, then it will be hard or impossible to see through the microscope.

Ques.2: When iodine reacts with starch, it produces a blue-black color. Starch is a white substance which plants use to store food. What structure did you see better because of the iodine? Why did you see this structure better?

Ans: Amylose in starch is responsible for the formation of a deep blue color in the presence of iodine. The iodine molecule slips inside of the amylose coil.

This makes a linear triiodide ion complex with is soluble that slips into the coil of the starch causing an intense blue-black color.

Due to this, we can see the structure better.

Ques.3: From low power to high power, what structures became clearer in the stained onion tissue?

Ans: From lower to higher power, we can see:-

-- Large, rectangular interlocking cells,

-- Clearly visible distinct cell walls surrounding the cells,

-- Dark stained nucleus,

-- Large vacuoles at the center,

-- Small granules may be observed inside the cells (within the cytoplasm)

Ques.4: What is the shape of an onion cell?

Ans: The shape of an onion cell is rectangular or square in shape.

User Zaxliu
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