Exam 2, Part 2


You have 1 hour and 30 minutes to complete this part of the exam.
Write your responses to the questions on the answer sheet provided.
Each response is worth up to 3 points unless otherwise noted.
You may use your notes, any textbooks and the Internet.

All responses must be in your own words, with sources mentioned (no need to formally cite, but do give credit) when applicable. Plagiarism of any kind will be reported to the Lesley University Academic Integrity Committee.

1. Below is a painting by David Goodsell depicting a mycoplasma cell which has a diameter of 0.25µm (micrometers). The orange strands running throughout the interior is DNA. Ribosomes are shown in magenta, while phosopholipids are show in light green.

a. Based on the information presented here, is mycoplasma a prokaryote or eukaryote? Give two reasons why.

b. Mycoplasma can cause illness in humans. If a mycoplasma cell is found by a macrophage (a type of immune system cell), it will be taken into the macrophage to be digested and rendered harmless. What is this process is involved in this phenomenon and what steps are involved?
mycoplasma Continue reading


Exam Review: Cell Biology & the Immune System

The immune system is extraordinarily complex, even when we’re just considering a small injury, but we can start to make sense of what’s going on with material we’ve covered. As a way to prepare for Monday’s exam, try to apply the key terms covered in this section of the course to the video below by Kurzgesagt. If you’d to get to know the immunology as it pertains to skin in more depth, check out the video by Nature also below.

Continue reading

In Class Mar. 23: cell biology in the news

scisource_bs6014_custom-5b0642ce9e8a3bb9455448dc159e81c4314c9df5-s600-c85 Today we’ll take a brief look at the following recent news stories:

To test your knowledge of cell biology, consider these questions: Are the cells in these articles prokaryotic or eukaryotic? What kind of microscopes are being used to visualize these cells? Which of these cells are motile? What gives them their motility?

In Class Mar. 21: a rendition of the plasma membrane

For this activity, we’ll need 8 volunteers:

  • 6 of you will each be a phospholipid with your hydrophobic arms held out in front of your hydrophilic torso;
  • 2 of you will each be a protein with your hydrophilic arms extended out to the sides of your hydrophobic torso.

And you’ll do two things:

  1.  First, phospholipids, how will you arrange yourselves together if you’re in an aqueous environment (i.e. surrounded by water molecules)?
  2. Proteins, how will you situate yourselves relative to these now nicely arranged phospholipids?

Did this work out as planned? Hit the “Read More” link to find out.  Continue reading

Class Prep for Mar. 21: cell biology reading

Finish reading the cell biology chapter of the textbook you’re using for the course and bring in any questions you’d like to discuss. Try to get a good feel for the components of the endomembrane system and how they work together. Also consider how osmosis works.

As discussed today in class, we’ll have a quiz on Monday. Also, our next exam, which will focus on cell biology, is tentatively planned for Mar. 28.