‧Reproduction
Unlike multicellular organisms, increases in the size of bacteria (cell growth) and their reproduction by cell division are tightly linked in unicellular organisms. Bacteria grow to a fixed size and then reproduce through binary fission, a form of asexual reproduction.
The following is the process of bacteria' s cell divide:
1. Cell elongates and DNA is replicated
2. Cell wall and plasma membrane begin to divide
3. Cross-wall forms completely around divided DNA
4. Cells separate
picture from:http://www.uic.edu/classes/bios/bios100/lecturesf04am/binfission.jpg
There is also a video, this is about the bacteria growth. Show you how bacteria divide. http://tw.youtube.com/watch?v=gEwzDydciWc
‧Phases of growth
According to the life of bacteria, we can plot a bacterial growth curve to show the change in over time. There are four bacis phases of growth: the lag, log, stationary, and death phases.
-Lag phase: production of new enzymes needed for growth
-Log phase: maximum growth
-Stationary phase: growth = death; nutrients or waste products limiting growth
-Death phase: death > growth; lack of nutrients or accumulation of waste products killing cells
picture from:http://microvet.arizona.edu/Courses/MIC205/Exams/05Exams/06-14_BacteriaGrowth_1.jpg
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thank you! This helped me a lot on my homework assignment :)
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