Q: If a bacterial cell is measured to be 2 $$\mum in $$diameter, how many nanometers is this?

$$2 \mu\text{m} = 2 \times 10^3$ \text{nm} = 2000 \text{nm}$$

Question 1

Which of the following statements best describes the third principle of the cell theory as postulated by Pasteur and Virchow?

Accepted Answer

All cells arise only from preexisting cells.

Question 2

A scientist is using a microscope to observe the surface structure of pollen grains in three dimensions at very high magnification. Which type of microscopy is most appropriate for this application?

Accepted Answer

Scanning electron microscopy (SEM)

Question 3

If a bacterial cell is measured to be 2 $$\mum in $$diameter, how many nanometers is this?

Accepted Answer

$$2 \mu	ext{m} = 2 	imes 10^3$ 	ext{nm} = 2000 	ext{nm}$$

Question 4

Which of the following is a key advantage of fluorescence microscopy over brightfield microscopy for studying protein localization in living cells?

Accepted Answer

It enables detection of specific proteins using fluorescently labeled antibodies.

Question 5

A researcher wants to separate cellular organelles based on their size and density. Which technique should they use?

Accepted Answer

Subcellular fractionation using centrifugation

Question 6

Which historical experiment first demonstrated that biological molecules could be synthesized outside of living organisms, challenging the idea of 'vitalism'?

Accepted Answer

Fredrich Wöhler's synthesis of urea in the lab

Question 7

A scientist is studying the temporal and spatial distribution of a protein in a living cell. Which tool would be most useful for this purpose?

Accepted Answer

Green fluorescent protein (GFP) tagging

Question 8

Which of the following statements about the central dogma of molecular biology is correct?

Accepted Answer

It describes the flow of genetic information as DNA $$\rightarrow$$ RNA $$\rightarrow$$ Protein.

Question 9

Which measurement unit would be most appropriate for describing the diameter of a DNA double helix?

Accepted Answer

Angstrom ($$	ext{\AA})$$

Question 10

A student is comparing the advantages and disadvantages of light microscopy and electron microscopy. Which statement is true?

Accepted Answer

Light microscopy is less expensive and can be used to observe live specimens.

Question 11

Which scientist's work laid the foundation for the chromosome theory of heredity by connecting specific traits to specific chromosomes in Drosophila melanogaster?

Accepted Answer

Morgan, Bridges, and Sturtevant

Question 12

A researcher is using restriction enzymes to cut DNA and insert a gene from one organism into another. Which technology is being used?

Accepted Answer

Recombinant DNA technology

Question 13

Which of the following is a disadvantage of transmission electron microscopy (TEM) compared to light microscopy?

Accepted Answer

TEM requires expensive equipment and extensive training.

Question 14

Which of the following best describes the role of bioinformatics in modern cell biology?

Accepted Answer

It merges computer science with biology to organize and interpret large-scale biological data.

Question 15

A scientist wants to monitor the expression levels of thousands of genes simultaneously in a cancer cell line. Which high-throughput method should they use?

Accepted Answer

Microarray analysis

Question 16

Which of the following statements about scientific 'facts' is most accurate according to the philosophy of science described in cell biology?

Accepted Answer

Scientific facts are provisional and subject to change based on new evidence.

Question 17

A researcher designs an experiment to test the effect of a new drug on cell division. The drug concentration is varied, while all other conditions are kept constant. What is the independent variable in this experiment?

Accepted Answer

The drug concentration

Question 18

Which of the following is NOT a strand of biological inquiry that contributed to the emergence of modern cell biology?

Accepted Answer

Physiology

Question 19

A scientist is using electrophoresis to separate DNA fragments. What property of the DNA fragments determines their movement through the gel?

Accepted Answer

Their size and charge

Question 20

Which of the following statements about model organisms is correct?

Accepted Answer

Model organisms are species that are well characterized and easy to manipulate for experimental studies.

Chapter 1: A Preview of Cell Biology – Foundations, Microscopy, and the Emergence of Modern Cell Biology

Guida di studio - Domande di pratica

Study guide - Flashcard