Unit 1 Cells (ECOMM)

One characteristic of all living things is that they are made of units. What are these units called?

• Tissues

• Cells

• Organs

• Body Segment

Which statement is correct?

• Most single celled organisms can be seen with a hand lens.

• People can see blood cells if they are viewed under a microscope.

• People can see cell walls under a microscope but not the nucleus

• The cell’s nucleus looks larger under a microscope than a cell’s membrane.

Kelly is studying cells. She planned an investigation to view a plant leaf using a hand lens, a microscope and with the naked eye then record her observations. The results of the investigation are shown below.

Which claim is supported by the evidence in the investigation?

• Kelly observed plant cells through the microscope and magnifying glass because cells are too small to be seen with the naked eye.

• Kelly observed plant cells through the hand lens because cells are too small to be seen with the naked eye.

• Kelly observed plant cells through the microscope because cells are too small to be seen with the naked eye.

• Kelly observed plant cells through the naked eye, microscope and magnifying glass because cells are too small to be seen with the naked eye.

During a science lab Jose viewed onion cells at two different magnifications then recorded his findings on his lab recording sheet. An example of his lab sheet is shown below.

Which explanation best explains the differences between the images at different magnifications?

• Cells can only be viewed through magnification and the details within each cell changes at different magnifications. The stronger the magnification the more details are seen.

• Cells can only be viewed through magnification and the details within each cell does not change at different magnifications. The stronger the magnification the same details are seen.

• Cells can only be viewed through magnification and the details within each cell changes at different magnifications. The stronger the magnification the fewer details are seen.

• Cells can only be viewed through magnification and the details within each cell does not change at different magnifications. The stronger the magnification the more details are seen.

Tracy is comparing a small piece of a leaf and part of a butterfly wing. She places the leaf under one microscope and the butterfly wing under another microscope. The images she sees in the microscope are shown to the right. Based on her observations, which statement is correct?

• Both the leaf and the butterfly are made up of cells

• The leaf is made up of cells but the butterfly wing is not

• The butterfly wing is made up of cells but the leaf is not

• The leaf and butterfly wing are not made up of cells

Mark can see little rectangles when he looks at the cells of an onion skin with a microscope, as shown in the diagram above. His teacher asks him to identify what he is observing and explain how he came to that conclusion. Based on his observations, which conclusion would be the best answer?

• The onion skin has this pattern because it is old. The lines and wrinkles can be seen with the microscope.

• It has little rectangles that are scales that protect the onion and give it shape.

• The rectangles are plant cells that can only be seen through a microscope. The cells are the building block of living things and an onion is a living thing.

• The rectangles are the same shape and do not move. The onion skin is made of non-living material. The rectangles give it shape.

A group of students want to prove that living things are made up of cells. Who would have the most effective way to design an investigation to collect evidence to support their claim?

• Tom would like the group to observe an insect closely and draw each body part in a science notebook.

• Carlos would like the group to use a magnifying glass or hand lens to observe a flower petal before and after it is crushed. The two observations would be recorded and compared using a chart.

• Maria would like the group to use a microscope to observe a soil, rock and salt sample. They would draw the cells in their science notebook and create a Venn diagram to compare and contrast each item.

• Keisha would like the group to use a thin piece of an elodea plant and place it under a microscope. A model is made from the observation and it is labeled. They would then compare it to the skin from the leaf of a cabbage and root hairs from a plant. The group would make a comparison chart to record their observations.

Students in a 5th grade classroom were discussing how magnification tools impact how scientists see the cells in plants and animals.

Which student has the best explanation of the impact of the tools listed in the chart above?

• Student 1 says that both the hand lens and microscope allows us to see the cells in plants and animals.

• Student 2 says that all of the magnification tools allows us to see the cells in plants and animals.

• Student 3 says that only the microscope allows us to see the cells in plants and animals.

• Student 4 says that only the hand lens allows us to see the cells in plants and animals.

A student in a 5th grade classroom was put to the test to identify cytoplasm in a plant leaf. Which of the following ways is the best for the student to gather evidence?

• The student can use the naked eye and hold the plant close to their face and identify the cells.

• The student can use a hand lens and study the ridges on the leaf to identify the cells.

• The student can use a telescope to zoom in closely on the leaf and identify the cells.

• The student can use a microscope to zoom in closely on the leaf and identify the cells.

Refer to the diagram to the right. Which structure is labeled “W”?

• chloroplast

• cell wall

• cytoplasm

• nucleus