Background: Prokaryotic vs. Eukaryotic Cells -...
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1 • How are prokaryotic and eukaryotic cells the same? How are they different? • How do eukaryotic and prokaryotic cells compare in scale? B.4A: Prokaryotic and Eukaryotic Cells Cell Structure and Function Background: Prokaryotic vs. Eukaryotic Cells A cell is the smallest and most basic structural unit of all living things. The word cell comes from a scientist in 1665 named Robert Hooke who was examining a piece of cork under a microscope. The word cell derives from the Latin cellula, meaning “a small room”. Hooke thought the cork cells resembled the small rooms in which monks often lived. Cells can be divided into two broad groups: those that contain membrane-bound organelles, such as a nucleus, and those that do not. There are two basic cell types: eukaryotic and prokaryotic. Both have a cell membrane, cytoplasm, ribosomes, and DNA, but there also distinct differences. Prokaryotic cells are found in unicellular organisms such as bacteria. A prokaryotic cell lacks a true nucleus and membrane-bound organelles. Scientists believe that prokaryotic cells were the first living organisms on the planet due to their primitive structure. Eukaryotic cells are found in multicellular organisms such as protists, fungi, plants, and animals. Some eukaryotes, however, such as amoebas, or some algae and yeast, are unicellular organisms. A eukaryotic cell contains a true nucleus and membrane-bound organelles. These organelles allow for eukaryotic cells to increase in size as each are specialized to accomplish a specific task. As a result, eukaryotic cells are typically larger than prokaryotic cells. Most eukaryotic cell membranes are capable of forming vesicles to take in particles, a process called endocytosis, and release particles through exocytosis. Prokaryotic cells are not capable of performing these processes. Despite the differences, both cells perform similar life functions such as energy production, or respiration, and reproduction. Although the process of accomplishing these tasks is different, the end result is the same. cell membrane cytoplasm DNA cell membrane cytoplasm DNA Prokaryotic Eukaryotic Complete the Background section of your Student Journal before continuing to the investigation.
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Transcript of Background: Prokaryotic vs. Eukaryotic Cells -...
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• How are prokaryotic and eukaryotic cells the same? How are they different? • How do eukaryotic and prokaryotic cells compare in scale?
B.4A: Prokaryotic and Eukaryotic Cells Cell Structure and Function
Background: Prokaryotic vs. Eukaryotic Cells A cell is the smallest and most basic structural unit of all living things. The word cell comes from a scientist in 1665 named Robert Hooke who was examining a piece of cork under a microscope. The word cell derives from the Latin cellula, meaning “a small room”. Hooke thought the cork cells resembled the small rooms in which monks often lived. Cells can be divided into two broad groups: those that contain membrane-bound organelles, such as a nucleus, and those that do not. There are two basic cell types: eukaryotic and prokaryotic. Both have a cell membrane, cytoplasm, ribosomes, and DNA, but there also distinct differences. Prokaryotic cells are found in unicellular organisms such as bacteria. A prokaryotic cell lacks a true nucleus and membrane-bound organelles. Scientists believe that prokaryotic cells were the first living organisms on the planet due to their primitive structure. Eukaryotic cells are found in multicellular organisms such as protists, fungi, plants, and animals. Some eukaryotes, however, such as amoebas, or some algae and yeast, are unicellular organisms. A eukaryotic cell contains a true nucleus and membrane-bound organelles. These organelles allow for eukaryotic cells to increase in size as each are specialized to accomplish a specific task. As a result, eukaryotic cells are typically larger than prokaryotic cells.��� Most eukaryotic cell membranes are capable of forming vesicles to take in particles, a process called endocytosis, and release particles through exocytosis. Prokaryotic cells are not capable of performing these processes. Despite the differences, both cells perform similar life functions such as energy production, or respiration, and reproduction. Although the process of accomplishing these tasks is different, the end result is the same.
cell membrane cytoplasm
DNA
cell membrane
cytoplasm
DNA
Prokaryotic
Eukaryotic
Complete the Background section of your Student Journal before continuing to the investigation.
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Part I: Plan Your Investigation Your Mission: Compare and contrast prokaryotic and eukaryotic cells. In this descriptive investigation, you will examine a set of slides to identify, compare, and contrast prokaryotic and eukaryotic cells. In Part I of your Student Journal, create a Question of Inquiry that you will research. To plan your investigation, choose the equipment and any technology you need, note the important safety steps, and list the procedure steps you will follow. Part II: Implement your Investigation 1. Use your knowledge of microscopes to focus on each slide in order to identify the
specimens. Take turns focusing the microscope for each slide, so that all group members have observed the specimens with the microscope.
2. Each slide is labeled a number, which corresponds to the data table in Part II of your Student Journal. For each specimen, sketch an image of your observations.
3. Analyze each specimen and identify its cell type as either a prokaryotic or eukaryotic.
4. When your teacher reveals the name of each organism, write it appropriately in your data table.
B.4A: Prokaryotic and Eukaryotic Cells Cell Structure and Function
• How are prokaryotic and eukaryotic cells the same? How are they different? • How do eukaryotic and prokaryotic cells compare in scale?
Complete Part I and II in your Student Journal
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B.4A: Prokaryotic and Eukaryotic Cells Cell Structure and Function
Eukaryotic Cells
Prokaryotic Cell
• How are prokaryotic and eukaryotic cells the same? How are they different? • How do eukaryotic and prokaryotic cells compare in scale?
Use these images as a reference for your investigation
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B.4A: Prokaryotic and Eukaryotic Cells Cell Structure and Function
Organelle Function Membrane Bound?
Plant / Animal Size Picture
1 cell wall protects no plant 30µm thick
2 cell membrane barrier/
gatekeeper no both 0.009µ
m thick
3 chloroplast makes food yes plant 5µm
4 golgi body packages and sorts yes both 1µm
5 lysosome breaks down substances yes both 0.5µm
6 mitochondrion produces
energy yes both 5µm
7 nucleus control center yes both 10µm
• How are prokaryotic and eukaryotic cells the same? How are they different? • How do eukaryotic and prokaryotic cells compare in scale?
Use this chart as a reference for your investigation
Organelle Function Membrane Bound?
Plant / Animal Size Picture
8 ribosome make proteins no both 0.025µm
9 vacuole storage yes animal; small
plant; large
0.5µm 12µm
10 endoplasmic reticulum transport materials yes both
0.5µm thick
11 cytoplasm supports
organelles no both n/a
12 cilia movement no animal 10-15µ
m
13 flagella movement no animal 40-50µ
m
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• How are prokaryotic and eukaryotic cells the same? How are they different? • How do eukaryotic and prokaryotic cells compare in scale?
Use this chart as a reference for your investigation
B.4A: Prokaryotic and Eukaryotic Cells Cell Structure and Function
