Protein synthesis is accomplished primarily by the interaction of which two cell structures?

• vacuoles and mitochondria

• ribosomes and vacuoles

• nuclei and ribosomes

• nuclei and mitochondria

Answer explanation

nucleus has genetic instructions (DNA) to make protein, ribosome makes protein (RIBS)

Students did an experiment comparing the activity of four different enzymes, A, B, C, and D. The results are represented in the graph below. A valid conclusion based on the information in the graph is that

• the pH of some enzymes changes as the temperature changes

• enzymes change color in proportion to the rate of activity

• a difference in the pH of an environment changes enzyme activity

• enzyme activity causes acids to change into bases over time

Answer explanation

Look at the graph, as the x-axis _____________ the y axis ____________. As pH increases, the enzyme activity goes up and down (changes) for every enzyme. (NOTE - you don't need to know anything about enzymes to answer this question - you just need to interpret a graph)

The diagram below illustrates the movement of glucose across a cell membrane. Which two processes are most directly represented in this diagram?

• ATP synthesis and the diffusion of water

• molecule transport and energy use

• homeostasis and ATP synthesis

• homeostasis and the diffusion of water

Answer explanation

YES glucose is small enough to diffuse. In this picture, it is being pumped into a cell by active transport (this cell must need a lot of glucose to function). Since glucose is moving from low to high concentration, it is active transport, therefore ATP must be used. Tricky!

The diagram represents changes that take place within the human body. The diagram represents

• cellular differentiation

• dynamic equilibrium

• gene interaction

• biological evolution

Tags

NGSS.HS-LS1-3

An experiment is carried out to determine how different pH values of soil will affect the growth of tomato plants. In this experiment, the dependent variable could be the

• height of the tomato plants

• pH of the soil

• specific variety of tomato plants used

• pH of enzymes in tomato leaf cells

Answer explanation

dependent = DATA collected, what will you measure?

Tags

NGSS.MS-LS1-5

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Using microscopes he constructed in the 1600s, Antonie van Leeuwenhoek discovered a new microscopic world. His discoveries paved the way for the development of the microscopes used today and for many important biological breakthroughs. Which statement best describes van Leeuwenhoek’s work?

• His observations alone provided enough information to form modern biological theories.

• The microscopes he made were used by all scientists and have remained unchanged over the years.

• Knowledge gained by his work has led to the improvement and development of modern scientific concepts.

• Explanations of the microscopic world today are solely based on his observations and conclusions.

Answer explanation

Key idea: the work of many scientists over a long period of time has led to currently scientific ideas.

Tip: questions with ALL, or that idea, are usually wrong

The diagram below represents a lab setup. The artificial cell (dialysis tube) contains a starch solution and the beaker contains a solution of starch indicator and water. The setup is left undisturbed for twenty minutes. What change, if any, will be visible

• The liquid outside the cell will turn blue black

• Starch will diffuse out the the cell

• Starch indicator will diffuse into the cell, turning the cell blue black

• The setup will remain unchanged

Answer explanation

Starch stays where it starts, therefore outside the cell will not change color. Starch indicator (iodine) is small and will diffuse in. This will cause the inside of the cell to turn blue-black

Tags

NGSS.MS-PS1-2

A student added equal volumes of water to two different beakers. He then added blue food dye to one and yellow to the other. Next, he placed a white paper towel across the two beakers so that it went down into the liquid and connected the two beakers. After 20 minutes, the section of paper towel connecting the two beakers had turned color. The towel most likely turned green as a result of the

• separation of the dye molecules through the process of chromatography

• dyes moving across the towel due to the process of electrophoresis

• diffusion of the blue- and yellow-dyed water across the towel

• active transport of the blue and yellow food dyes

Answer explanation

Yellow and blue make green.

Tags

NGSS.MS-PS1-2

In single-celled organisms, materials are stored primarily in

• ribosomes

• mitochondria

• nuclei

• vacuoles

Tags

NGSS.MS-LS1-2

An ameba is a single-celled, heterotrophic organism. In order to meet its energy needs, it relies directly on the interaction of which cell structures?

• chloroplasts and the cell membrane

• the cell membrane and mitochondria

• nucleus and ribosomes

• vacuoles and the nucleus

Answer explanation

energy = mitochondria

cell membrane lets in raw materials to make energy in mitochondria

Tags

NGSS.MS-LS1-2

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