TEKS
Teacher Background for
Prokaryotic and Eukaryotic Cells
Biology
TEKS 4A
TEKS 4B (Expanded) Compare and contrast prokaryotic and eukaryotic cells.
How the TEKS Changed
1998 TEKS
2010–2011 TEKS
4A
4A
Identify the parts of prokaryotic and eukaryotic cells.
Compare and contrast prokaryotic and eukaryotic cells.
Unpacking the TEKS
Students explore the similarities and differences between eukaryotic and prokaryotic cells. Students should consider not just a cell’s structure, but also its life
cycle and place on the evolutionary tree.
Use TEKS Lesson 4A: Prokaryotic and Eukaryotic Cells to help students learn this material.
Related Content
TEKS 4A falls under knowledge and skills statement 4: The student knows that cells are the basic structures of all living things with specialized parts that
perform specific functions and that viruses are different from cells. TEKS 4A will give students a thorough understanding of the differences between the two
categories of cells: prokaryotic cells and eukaryotic cells. Students will come to understand that although they vary in their structure and function, cells are the
smallest functional units of any living organism. Students will explore detailed functions of cells in TEKS 4B; TEKS 4C explains that because they are not
made up of cells, viruses—though similar to cells in some ways—are not considered living. Specialized cells are explored under TEKS 5B.
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Content Refresher
Prior Knowledge
Cells fall into two broad categories defined
by whether or not their DNA is contained
within a nucleus: prokaryotic cells lack a
nucleus and eukaryotic cells have a nucleus.
Prokaryotes include the group of organisms
we call bacteria, while eukaryotes include
most organisms with which students will be
familiar.
Content and Vocabulary
Prokaryotes and eukaryotes differ in their
general size, cellular structure, mode of
reproduction, and classification. Nearly all
prokaryotes are unicellular organisms.
Exceptions to this general rule are the
myxobacteria. These prokaryotes form
multicellular fruiting bodies as part of their
life cycle. Eukaryotes may be unicellular,
such as a euglena, or multicellular, such as
animals, plants, and fungi. However, all
cells share a few characteristics such as the
presence of a cell membrane, DNA, and
ribosomes.
Activating Prior Knowledge
Students should have an understanding of the cell theory as well
as a working knowledge of basic cellular structure and function.
Although not explicitly required by the TEKS, students should be
able to identify the major eukaryotic organelles and explain their
functions.
cell theory: fundamental concept of biology that states that all
living things are composed of cells; that cells are the basic units of
structure and function in living things; and that new cells are
produced from existing cells
centriole: structure in animal cell that helps to organize cell
division
chloroplast: organelle found in cells of plants and some other
organisms that captures energy from sunlight and converts it to
chemical energy
endoplasmic reticulum: internal membrane system found in
eukaryotic cells; place where lipid components of the cell
membrane are assembled
Golgi apparatus: organelle in eukaryotic cells that modifies,
sorts, and packages proteins and other materials from the
endoplasmic reticulum for storage in the cell or release outside the
cell
mitocondrion: eukaryotic cell organelle that converts chemical
energy stored in food into compounds that are more convenient
for the cell to use
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Show students either models or photos of
a prokaryotic and eukaryotic cell. Ask
students what the differences are between
them (size, complexity, etc.). Then,
challenge students to recall the names and
functions of visible structures.
Misconception Alert
Some students may make the mistake of assuming that because they are smaller and less complex, prokaryotic organisms are “simple.” Remind students that
prokaryotes carry out all the activities of living things. They grow, reproduce, and respond to the environment. Further, as microscopes get more sophisticated,
scientists are discovering many prokaryotic structures that are homologous to eukaryotic organelles, such as cytoskeletons, chloroplasts, and mitochondria.
Covering the TEKS and Their Breakouts:
Students will master TEKS 4A when they read and answer:
Lesson Review Question 8 where they will (4Ai) compare prokaryotic and eukaryotic cells.
Lesson Review Question 8 where they will (4Aii) contrast prokaryotic and eukaryotic cells.
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