The origin of the first living organisms is called ________.
Many of the organic molecules associated with life can be created spontaneously under certain conditions. What do these conditions resemble?
Which was not a gas in Earth's earliest atmosphere?
What do scientists believe was the original genetic material able to copy itself without assistance?
By what means do bacterial cells typically divide?
Which protective structure forms to protect certain bacteria during periods of harsh conditions?
If you looked at unknown cells under a microscope, what could lead you to correctly conclude that they are bacteria cells?
They lack a nucleus.
Some bacteria have a spherical shape, called ________.
What is the strategy used by many prokaryotes for obtaining their energy and their molecular building blocks directly from inorganic chemicals?
Which are the smallest, least complex cell types?
Plants are in the domain ________.
Which statement is true regarding bacteria?
All pathogenic bacteria are harmful to humans.
Why is the conversion of atmospheric nitrogen (N2 gas) into ammonium (NH4) important for life on this planet?
Ammonium is a plant nutrient.
The practice of using bacteria to remove pollutants from the environment is called ________.
Food poisoning is often caused by a bacterium called ________.
What is the vector of Lyme disease?
Which was first on the planet, prokaryotes or eukaryotes?
There are more helpful types of bacteria on this planet than harmful types.
Which is not a method of introducing new genes into a bacterium?
Viruses that infect bacteria are called ________.
Which version of "bacterial DNA transfer" involves a physical connection between the two bacteria cells?
Which of the following is a form of reproduction in bacteria?
Neither of these
Are all bacteria in a colony genetically identical?
No, there are ways for bacteria to acquire new genetic material.
Which structure is not part of the endomembrane system?
What do the nucleus and the smooth endoplasmic reticulum have in common?
Their membranes are interconnected.
What is the leading scientific theory on how the first nuclear membrane originated?
From the inward folding of the plasma membrane
When did the first eukaryotic cell form?
About a billion years after the first prokaryotic cell was formed
What do the nucleus and mitochondria have in common?
They both contain DNA.
When a plant cell divides, how would you expect its chloroplasts to divide?
Which organelle could you remove and the cell would still survive?
All organelles are required for the survival of the cell.
Which organelle can survive outside of the cells?
No organelles can survive outside the cell.
What might be the advantage to a cell if it assimilated an ingested photosynthetic bacterium rather than digesting it?
It could now use sunlight to make its food.
Which protist group includes members with plantlike traits such as chloroplasts and multicellularity?
By what means do the amoebas move?
Which of the terrestrial unicellular protists is an enormous cell with multiple nuclei?
While most biologists do not consider viruses to be alive, viruses do share some characteristics with living things. Which of the following is a required trait for life that viruses share with living things?
Having highly ordered structure
Which viral life cycle would result in a quicker death for an infected cell?
Medicine that prevents viral infections is a(n) ________.
Which of the following do not get infected by viruses?
All of these can be infected by viruses.
The misshapen version of a protein that causes properly folded proteins to misfold is the ________.
An infectious circular piece of RNA is the ________.
Which of the following infects only plants?
A degenerative brain disorder transmitted by cannibalism is called ________.
Halophiles are found in which environment?
Which organisms are called the extremophiles and flourish in extreme conditions?
Where would you expect to find methanogens?
In the digestive tract of cows
Which specific cells are infected by the HIV virus?
Helper T cells
Where would you find the double-stranded HIV DNA in an infected cell?
Incorporated directly into the host cell's chromosome