NYS Regents Biology Review

When preparing a wet mount slide of onion cells, a student put a drop of Lugol's iodine on the slide. This iodine was added to:

• prevent air bubbles
• make cell structures more visible
• increase the magnification
• increase the rate of photosynthesis in cells

A student views cheek cells under low power. Before switching to high power, the student should:

• adjust the ocular lens
• center the image being viewed
• adjust the course adjustment to move the stage away from the slide
• remove the slide from the stage

Paper chromatography is a laboratory technique that is used to 

• separate different molecules from one another
• stain cell organelles
• indicate the pH of a substance
• compare relative cell sizes

A student observes a red onion cell with a compound light microscope using low, then high power. The two views are represented in the picture.
The best explanation for the changes observed by the student is that, when switching from low to high power, the

• diameter of the field of view decreases
•  slide was accidentally moved
• diameter of the field of view increases
•  image is inverted and reversed

A student observes a red onion cell with a compound light microscope using low, then high power. The two views are represented in the picture.
Which diagram represents where the cell should be located in the low-power field of view to be sure the entire cell will be visible after switching to high power?

• 1
• 2
• 3
• 4

Bromthymol blue turns yellow in the presence of carbon dioxide. This characteristic makes it possible for bromthymol blue to function as:

• a measure of volume
• an energy source
• a catalyst
• an indicator

After switching from the high power to the low power objective lens of a compound microscope, the area of the low power field will appear: 

• Larger and brighter
• Smaller and brighter
• Larger and darker
• Smaller and darker

The diagram represents a technique used in some molecular biology laboratories
This technique is a type of

• chromatography
• gel electrophoresis
• direct harvesting
•  genetic engineering

Tags

NGSS.MS-LS4-5

Which chemicals are used to cut DNA into fragments for a gel electrophoresis procedure?

• enzymes
• molecular bases
• hormones
•  ATP molecules

The parents of a new baby believe they brought the wrong child home from the hospital. Gel electrophoresis was performed using DNA samples from the parents and the child. A section of the gel electrophoresis results are shown in the diagram.
Which conclusion is valid based on the gel electrophoresis results?

• They have the correct child, because her genetic information is identical to that of the father.
• They have the wrong child, because her genetic information does not match that of either parent.
•  They have the correct child, because her genetic information came from both parents.
• They have the wrong child, because her genetic information matches only that of the mother.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2