Plant Cell Adaptations

Author’s Name: Elizabeth Morrison

Length of lesson: 45 minutes

Name of course: Biology

Grade level: 9

TEKS addressed:

(2.C)  Scientific processes. The student uses scientific methods during field and laboratory investigations. The student is expected to organize, analyze, evaluate, make inferences, and predict trends from data.

(4.A)  Science concepts. The student knows that cells are the basic structures of all living things and have specialized parts that perform specific functions, and that viruses are different from cells and have different properties and functions. The student is expected to identify the parts of prokaryotic and eukaryotic cells.

(5.A)  Science concepts. The student knows how an organism grows and how specialized cells, tissues, and organs develop. The student is expected to compare cells from different parts of plants and animals including roots, stems, leaves, epithelia, muscles, and bones to show specialization of structure and function.

(13.A)  Science concepts. The student knows the significance of plants in the environment. The student is expected to evaluate the significance of structural and physiological adaptations of plants to their environments.

Concept(s)

Plant cells share certain common features, but cells in different parts of the plant have different modifications, specific to their task. Also, plant cells may be influenced by their environment.

Performance or learner outcomes

Students will be able to:

Utilize a microscope to observe plant cells

Identify plant cell organelles

Compare and contrast differences in plant and animal cells

Hypothesize what environments or functions cells might be adapted to based on structure?

Resources, materials and supplies needed

Microscopes

Plant cell slides (they can easily prepare slides with onion cells (membrane on onion and elodea, an aquatic plant that is only a few cells thick).

NOTE: HS students typically don’t learn to identify xylem and phloem specifically in bio I. It is most helpful to compare plant and animal cell structures or relate tissues to function.

Slides, cover slips

iodine

Safety Considerations

Use microscopes carefully. Review proper techniques for viewing and handling slides.

Supplementary materials, handouts

Worksheets

Five-E Lesson

Teacher Does Probing Questions Student responses

Misconceptions

Engage: Plant slides and microscopes will be set out when students enter classroom.

How do plant cells compare with animal cells? What organelles do plants have that animal cells don’t? Who can tell me what kind of organelles a plant has? Does every plant cell have all of these? Today you will look at slides of plant cells and see for yourselves.

Cell wall, chloroplast, central vacuole Yes/no

Explore: Students look at slides of different plant cell types (Be specific here – root, stem, leaf??) and note the differences and similarities they observe on your worksheet. They also sketch what they see. Then hypothesize as to the function of these cells by using the differences in their structure.

What do you see? What is different in the other cells? What is the same? What could that variation be useful for? What type of cell do you think this is? Where in the plant could you find it? What shape are plant cells? What structure gives them that shape?

Explain:

What do all these cells have? What varies? What cells would have these variations?

All have cell wall, most have central vacuole Some don’t have chloroplasts, some have thicker cell walls, some have nothing inside the cell walls (xylem are dead at maturity), some are full of amyloplasts, many different shapes, etc. Thicker cell wall for support, chloroplasts only in cells near surface where sunlight reaches, amyloplasts in tubers (underground storage), unusual cell wall in guard cells

Extend / Elaborate: Discuss environmental adaptation of plant cells.

What adaptations might a plant have at the cellular level in a wet environment have? A dry environment?

Vascular cells may be wider to allow more water to move through. Cells may divide faster. Thinner vessels, slower division, outermost cells have may have wax to keep in water. Roots may grow very deep to find water source.

Evaluate:

Worksheet will serve as evaluation as will discussion. Wrap up: so what organelles do plant cells have? Do they all have these? Why/why not? When would each be advantageous?

Name:__________________________________

Plant Cell Worksheet

	What organelles do you observe? Do you see anything else unusual (larger, smaller, missing)?	Sketch what you observe and label any parts you recognize.	Where in a plant might you find these cells?
Slide 1 – onion root
Slide 2 – elodea leaf
Slide 3 - ???
Slide 4