Week 18
LESSON 25: PLANT PHYSIOLOGY
Assignment:
1) Read textbook pages corresponding to this topic
2) Define the following terms:
Physiology, loam, topsoil, humus, root pressure, passive absorption, translocation, capillarity, transpiration-cohesion theory, pressure-flow model, nastic movement, turgor, fertilizers, mulch, auxins, abscissic acid, cytokinins, ethylene, tropism, etiolated, dormancy.
3) Watch lecture and take notes.
4) Complete review questions, and check answers.
LESSON 25 REVIEW QUESTIONS
Solutions are at the end of the video for this lesson.
1-10: Fill in the blanks using the following words. Each word should be used only one time. (1 pt. each)
Active transport, cohesion, gibberellin, gravity, insectivorous, leguminous, nastic, nitrate,
phosphate, photoperiod.
1)
Three ways that the mineral content of soils can be replenished are mulch, fertilizers, and crop rotation with __________________ plants.
2)
The transpiration-________________________ theory is used to explain the movement of water from roots to leaves of larger plants.
3)
The loss or gain of water by plant cells, resulting in visible movement of plant parts, is known as _______________________ movement.
4)
Thigmotropism is a plant’s response to touch, while geotropism is a plant’s response to _______________________.
5)
Connection to Lesson 6: Water can usually move from the soil into root cells passively by osmosis, while _____________________ is required to move minerals from the soil into the roots.
6)
__________________, or NO3- is a common ionic form of nitrogen that plants use.
7)
_______________________, or PO43-, is a common ionic form of phosphorous that plants use.
8)
_____________________ is a chemical messenger (hormone) that stimulates growth in stems and leaves.
9)
_________________________ plants obtain their nitrogen from insects, unlike most plants, which absorb nitrogen from the soil.
10)
Long-day plants will only flower when the ________________________ is greater than 12 hours.
11)
(5 pts.) Describe how a period of dormancy could be beneficial to a plant.
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LESSON 26: PLANT REPRODUCTION
Week 18
Assignment:
1) Read textbook pages corresponding to this topic.
2) Define the following terms:
vegetative reproduction, plantlet, pedicel, receptacle, pollen grain, pollen tube, micropyle, endosperm, seed, hilium, cotyledon, hypocotyl, germination, fruit
3) NO LECTURE, skip to step 4.
4) Complete review questions, and check answers.
5) Complete Biology Facts Quiz 5: Parts of The Plant.
LESSON 26 REVIEW QUESTIONS
Solutions are at the end of the video for this lesson.
1-6: Fill in the blanks using the following words. Each word should be used only one time. (1 pt. each)
Cotyledon, germinate, grafting, ovary, pistil, stamen, stigma
1)
Rhizomes, stolons, and tubers are natural forms of vegetative reproduction in plants, while ________________ is a common artificial form of vegetative reproduction. However, it is not “officially” reproduction, since no new plant is formed.
2)
In order for a seed to _____________________, the proper environmental conditions (moisture, sunlight,
oxygen, etc) must exist.
3)
When a pollen grain lands on a____________________, a pollen tube begins to form.
4)
The _______________ is also known as the fruit.
5)
The purpose of the _________________ is for energy(food) storage, which the young plant will need once it germinates.
6)
The _______________ is the female reproductive structure and the ___________________ is the male reproductive structure on a plant.
7)
(8 pts.) Identify the following parts on this cross section through a flower: stigma, style, ovary, ovule, anther, filament, petal, and sepal.
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Laboratory Activity
16
Week 18
Transpiration
Fulfills AP® Biology Lab Requirement
Introduction
In Laboratory Activity 2, you observed how water passes through cell membranes by osmosis. Plants obtain most
of their water by osmosis through the roots. The water then travels through adjacent cells until it reaches the xylem, a tube-like structure that carries the water up the stem and out to the leaves. Water is necessary for photosynthesis
and other cellular processes. Plant leaves contain openings called stomata, where gases are exchanged. Water loss
through the stomata is referred to as transpiration. In Laboratory Activity 16, you will investigate factors that affect
the rate of transpiration in plants. You will use the scientific method to answer the following question:
Of the following variables, heat/light, wind, and humidity, which will cause the greatest
change in a plant's transpiration rate?
Hypothesis:(look up in a reference book, textbook, or web page)
Methods
Equipment: Digital balance, weighing dishes, bean seeds or young plants with 1/8" dia. stems, 5 feet of 1/8" i.d. plastic tubing, 1 mL graduated pipet (0.01 mL increments), metric ruler, ring stand, test tube clamps, tape, heat lamp, fan, plastic bag, stopwatch, silicon sealant, eyedropper, microscope, slides, cover slips,
preserved slides of Ranunculus (buttercup) stem and root, spinach or similar leaf, dissection scissors,
tweezers, permanent marker, Microsoft Excel or similar program, water.
Procedure: Refer to video lab. Record your data on the following page:
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Week 18
Distance on pipet that equals 0.2 mL = ________________in.
0 min.
5
10
15
20
25
30
Control distance(in.)
Control volume (mL)
Temp./Light distance(in.)
Temp./Light volume (mL)
Wind distance(in.)
Wind volume(mL)
Humidity distance(in.)
Humidity volume (mL)
Mass of 4, 1 cm2 leaf sections = ____________g
Treatment
Control
Leaf mass (g)
Leaf area (m2)
Temp./Light
Wind
Humidity
Results
Calculate the mass, in grams of 1 m2 of leaves. Mass of 1 m2 = ________________g
Water Loss (mL/m2)
Control
0 min.
5
10
15
Temp/Light volume
Wind volume
Humidity volume
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20
25
30
Week 18
Water Loss (mL/m2)
60
40
20
0.0
0
10
20
30
40
Time (minutes) Discussion:
1. Was your hypothesis correct? Why or why not?
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions
that could be answered by conducting a science experiment.
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Week 18
Observing cells involved in transpiration
Observe a preserved slide of Ranunculus root and sketch a pie-shaped section and label. Include xylem, phloem,
cortex, and epidermis.
Ranunculus root dia.=_________μm Observe a preserved slide of Ranunculus stem and sketch a pie-shaped section and label. Include vascular bundle,
cortex, pith, and epidermis.
Ranunculus stem dia.=_________μm Observe stomata from a spinach leaf. Sketch a section and label. Include several guard cells and stomata, and epidermal cells.
Stomata length=_________μm 111
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