topic : plants aim : describe the role of tropisms in plants

Topic: Plants

Aim: Describe the role of tropisms in plants.

Do Now: Evolution and Plant review

HW: Define: ecology, ecosystem, biotic factors, abiotic factors, population, community, producers, consumers, herbivores, carnivores, predators, scavengers, omnivores, decomposers, habitat, niche

Food chain reading notes due Tuesday

CL Evolution due Wednesday.

The diagram above shows a series of bone structures in four different species of vertebrates.

1. What are these structures called?

2. Explain how these structures support the theory of organic evolution.

Homologous structures

Because these species have similar structures, they may have evolved from a common ancestor.

1. Identify the common ancestor.

2. Identify the species that are NOT extinct. Explain why they are still present.

3. Identify a species that has become extinct and explain why.

4. Which part of Darwin’s theory does this diagram represent? Support your answer.

A

J, K, M

They had favorable adaptations that enabled them to adapt to their environment.

O, P, H, C, DThere was no variation within the species.

SpeciationOne species evolved into many species over time.

PHOTOSYNTHESIS AEROBIC RESPIRATION

Energy is stored. Energy is released.

H2O and CO2 are raw materials C6H12O6 and O2 are raw materials

C6H12O6 and O2 are products H2O and CO2 are productsTakes place in chloroplasts Takes place in mitochondria

1. The substance in green plants that captures the sun’s energy is _____.

2. The process in which light energy is converted into chemical energy is known as ____.

3. A process in which glucose is broken down to release energy is called ___.

4. The plant structure that absorbs water and minerals from the soil are _____.

5. The tissue found in stems and leaves that transport materials throughout the plant is called _______ tissue.

Chlorophyll

photosynthesis

Cellular respiration

roots

vascular

1. The raw materials of photosynthesis are _____.

2. The vascular tissue that transports water up from the roots to the leaves is _____.

3. Plants that use photosynthesis are ______.

4. The source of energy for photosynthesis is _____.

5. The vascular tissue that transport food throughout the plant is called _______.

6. The “chemical energy” produced during photosynthesis is _______.

7. The waste gas released by plants is ____.

8. In a plant, photosynthesis occurs in _____.

9. The wavelengths of light that are most effective for photosynthesis are _________________.

CO2 and and H2O

xylem

autotrophs

sunlight

phloem

glucose

oxygen

leaves

red and blue

1. Identify some external stimuli that plants respond to.

• Tough, light gravity

2. Describe tropisms.

• Movement caused by a change in growth

3. Describe the difference between a negative and positive tropism.

•Negative: plant grows away from stimulus

•Positive: plant grows towards the stimulus

4. Describe how plants respond to the following stimuli:

What is the external stimulus for this plant response?

What is the external stimulus for this plant response?

a. Touch

• Plant bends and twists around any object it touches

• Thigmotropism• Positive tropismhttp://www.youtube.com/watch?v=_SIJ4ov_FxA

What is the external stimulus for this plant response?

b. Light • Plant bends toward light• Phototropism• Positive tropism

What is the external stimulus for this plant response?

c. Gravity

• Roots grow downwards• Stems grow upwards• Gravitropism or

Geotropism

•Roots - Positive tropism

•Stems - Negative tropism

http://bcs.whfreeman.com/thelifewire/content/chp38/3802001.html

http://www.youtube.com/watch?v=F3Oj2er-91s&feature=related

What is the external stimulus for this plant response?

d. Water

•Hydrotropism• Plant grows towards water• Positive

5. Describe auxins.

• Plant hormones that causes plants to respond to stimuli.

Observe the diagram above. In which part of the plant are auxins produced?

Tips were removed

Tips covered

6. Identify the

kind of responses regulated by auxins.

• Development of flowers, roots and fruits

• Control production of other plant hormones.

7. Observe

Figure 12 on p. 314.

Describe how auxins cause plants to bend towards the light. .

• Auxin levels increase in cells of shaded area.

• Causes greater elongation of cells which results in the bending of the plant.

Let’s summarize….

1. Describe tropisms.

2. What are some examples of external stimuli that cause tropisms?

3. Explain phototropism.

4. Explain geotropism.

5. Explain thigmotropism.

6. Explain hydrotropism

Plant substances that affect plant growth are called

1. tropisms

2. glucose

3. germination

4. hormones

Plant response to a stimulus is called

1. photosynthesis

2. transpiration

3. tropism

4. locomotion

An example of a negative tropism is

1. stems growing up and away from gravity

2. plants bending towards light

3. roots growing down towards gravity

4. Plants growing towards a water source

1. What part of Darwin’s Theory of Natural Selection is this diagram representing?

Variation2. Which has the favorable adaptation? Support

your answer.

Medium mice. They have the greatest population.

Identify The parts to Darwin’s Theory of Natural Selection.

1.Differences among the organisms within a species exists.

2.A species produces more offspring than can actually survive.

3.Organisms will struggle with each other for limited resources.

4.Overtime, a species can evolve into different species.

5.Organisms that are most fit will survive, reproduce and pass on the trait to offspring.

Variation

Overproduction

Competition

Speciation

Survival of the fittest

  According to one theory, similarities in these embryos suggest common ancestry. As these embryos mature, they will most likely 

(1.) develop new organs according to the nutritional requirements of each organism 

(2.) show no similarity as adults  (3.) continue to closely resemble each other as

adults  (4.) develop the distinctive characteristics of their

species

According to Charles Darwin, one factor that affects the evolution of a species is 

(1.) variation due to genetic mutations  (2.) rapid fossil formation  (3.) survival of the fittest  (4.) exposure to environmental pollutants

Which of the following is most likely to cause an organism to become extinct?

1.A mutation develops.

2.The major change in the environment occurs and organisms cannot adapt.

3.DNA is not readily passed on to offspring .

4.Malnutrition occurs over an organism’s lifetime.