Bacteria Basics
These tiny organisms are responsible for many of the infections studied in this chapter.
Bacteria
If a bacterial population increases inside a host, the number of bacteria can change dramatically because each generation can produce additional bacteria. This demonstrates what kind of population growth?
What is exponential growth?
A proposed explanation that can be tested with evidence is called this
What is a hypothesis?
This molecule stores hereditary information in bacterial cells.
What is DNA
A scientist notices that a bacterial population increases after being placed in a nutrient-rich environment. The increase is an example of this.
What is population growth?
Bacteria can reproduce by making a copy of their genetic material and then splitting into two cells.
binary fission
hen harmful bacteria enter and grow in the body, this can happen.
What is an infection?
Scientists can use mathematical or visual representations to help explain how bacteria populations change. These are called this.
What are models?
DNA is found inside the cells of bacteria. True or false?
True
hy is evidence from multiple experiments generally more useful than a result from one experiment?
What is repeated evidence can show whether a pattern is consistent and reduce the chance that one unusual result explains the conclusion?
Bacteria are usually made of how many cells?
What is one cell?
An infection can make you feel sick because bacteria can damage cells and tissues or interfere with normal body what?
What is function
Scientists collect this when they investigate a scientific question.
What is data?
If a mutation gives one bacterial cell a trait that allows it to survive better than other bacteria in a particular environment, that trait can become more common through this process.
What is natural selection
A scientist observes that bacteria grow faster when more nutrients are available. What variable is being investigated?
What is the availability of nutrients?
Bacteria are too small to see with just your eyes, so scientists use this instrument to see them.
What is a microscope?
A bacterial population doubles every 30 minutes. If it starts with 100 bacteria, how many would there be after 2 hours?
What is 1,600 bacteria?
What are the conditions bacteria need to grow?
Space, nutrients, moisture, warmth
What is the basic unit of life?
The cell
A graph shows a bacterial population increasing rapidly over time. What can you infer from the graph?
What is the bacteria are reproducing and the population is increasing?
Unlike human cells, bacteria do not have this membrane-bound structure containing their DNA.
What is the nucleus?
A graph of bacterial growth starts slowly, then becomes extremely steep. What does the steep portion indicate about the rate of population growth?
What is the population is increasing at an increasingly rapid rate because each generation produces more bacteria?
A scientist changes one factor to determine how it affects bacterial growth. What is the factor being changed called?
What is the independent variable?
Do bacterial cells have a nucleus?
No
Researchers observe that bacteria with a particular inherited characteristic survive while other bacteria die. After many generations, most of the population has that characteristic. What does this pattern suggest?
What is natural selection?