Exam 1: Introduction to the Study of Cell and Molecular Biology

Virtually all chemical changes that take place in cells require ________,molecules that greatly increase the rate at which a chemical reaction occurs.

Techniques for sequencing DNA have become very rapid and cost-efficient.Consequently,researchers have begun to sequence all of the genes of all of the microbes present in a given habitat.What term has been coined to describe such a collective genome? What information does such a collective genome provide? What is an example of a microbiome?

What are embryonic stem (ES)cells? How do ES cells differ from adult stem cells?

What are glial cells?

Which of the following statements about viruses is not true?

You are conducting an experiment by trying to reproduce the work performed in 1891 by Hans Driesch,a German embryologist.You are working with a fertilized sea urchin egg and allow it to complete the first cell division after fertilization.You then carefully separate the two cells of the embryo and allow their development to continue.Based on Driesch's experiment,which result below would you expect to happen?

What major feature distinguishes the theoretical first eukaryotic common ancestor (FECA)from prokaryotes?

Prokaryotic cells are generally smaller than eukaryotic cells and have no membrane-bound organelles,which act to transport some materials around the cell and compartmentalize certain cellular processes.Why do prokaryotic cells not require such membrane-bound organelles?

What is the most appropriate unit of measurement for most types of cells?

The apical ends of intestinal cells face the intestinal channel and have long processes that facilitate the absorption of nutrients.What is the name of these processes and what cytoskeletal element forms their internal skeleton?

In some cases,an infecting virus does not lead to the death of the host cell,but instead integrates its DNA into the DNA of the host cell's chromosomes.Integration of the viral DNA can have different effects like exhibiting normal behavior until exposure to a stimulus that activates the dormant viral DNA,production of viral progeny that bud off of the infected cell or a loss of control over growth and division leading to malignancy.Such an infection is referred to as a(n)______ infection.

Despite being correct about the first two tenets of the Cell Theory,Schleiden and Schwann made an error about another central feature of cells.What was their error?

Bacteria will often pass a piece of DNA from a donor bacterial cell to a recipient bacterial cell presumably through a structure called a pilus.What is this process called?

Which of the following characteristics is(are)a basic property of cells?

The first compound light microscopes were constructed by the end of the sixteenth century.What is a compound microscope?

Bacteria often live in complex,multi-species communities,like the layer of plaque that grows on your teeth; such a community is called a(n)_________.

What advantageous uses have viruses been shown to have?

It was long thought that cell differentiation was irreversible,i.e.,once a cell like a fibroblast,a white blood cell or a cartilage cell has differentiated,it could not revert to any other cell type.Surprisingly,this is not the case.Shinya Yamanaka and his colleagues have succeeded in reprogramming a fully differentiated mouse cell,specifically a type of connective tissue fibroblast,into a pluripotent stem cell.How was this stunning feat accomplished? How did they demonstrate that iPS cells were indeed pluripotent?

What characteristics distinguish prokaryotic and eukaryotic cells?

You are studying an infectious agent,the effects of which resemble a virus.You isolate the agent and treat it with an enzyme that degrades proteins and it is unaffected.However,if treated with RNase,it loses its infectivity.What kind of pathogen is it most likely to be?