Looking at the onion root tip under the microscope you can see large, rectangular cells with visible distinct cell walls surrounding it (cells have a more regular shape because of the wall). Inside the cells, you can notice darkly stained nucleus, large vacuoles at the center and sometimes small granules within the cytoplasm. Looking the onion root tip under the microscope is often the way to observe mitosis. Usually, you cannot see organelles such as mitochondria, ribosomes, rough and smooth endoplasmic reticulum, centrioles and Golgi body as they appear translucent and because are too small to be seen under the light microscope (electron microscope required). Also, chloroplasts are not present in an onion cell because it is not a photosynthetic cell.
A batsman is unlikely to score a century in every cricket match. This is an example of "partial reinforcement".
<u>Option: C</u>
<u>Explanation:</u>
Unlike constant reinforcement, partial reinforcement is only strengthened during certain times or time ratios, rather than emphasizing the action every single time. This method of arranging reinforcement is also called intermittent reinforcement after certain number of correct answers or certain interval of time. Thus here a batsman donot plan intentionally to make a century in every cricket match, but it goes random. Although when they need to score high on pressure, they force themselves to stretch as much possible which is not general.
Answer: Hypertonic Environment
Explanation:
The salt solution and sugar solution is used for the process of food preservation as the bacteria and microorganism are not able to grow in such conditions that is being created by the solution.
The amount of the solute is more and the solution is less concentrated. The bacteria cell has less solutes and more solvent.
As per osmosis the water from the salt or sugar solution moves out from bacterial cell shrinks and dies.
This is how the bacterial cell dies and the food is prevented from spoilage.
Answer:
C.Both Gram positive and Gram negative cells would appear purple.
Explanation:
Gram staining is a technique used to differentiate bacteria to two main groups based on their difference in cell wall components.
Crystal violet, decolorizer(ethanol) and a counter stain are used.
Gram positive bacteria have a thicker peptidoglycan layer hence they will retain the crystal Violet stain even after decolorization. They will stain purple
Gram negative will stain pink due to losing the initial stain and taking up the counter stain after decolorization.
Therefore, if water is used instead of ethanol. Both bacteria will retain crystal violet stain in their cell wall.
