Name: __________________________________ Date: __________________ Period: ________

7.2 Tropism, Water Regulation, and Seed Dispersal

Do First: Answer the 6 questions in your Do First Answer Document.

■ One of the characteristics of living things is responding to ____________.– _______________ are growth or movements that respond to external stimuli or signals

■ They are important because plants are often primarily rooted in one place, but still need to be able to __________________ to changes in the environment and fulfil their needs.

What best explains the reason why it is important for plants to exhibit tropisms?a) these tropisms help plants in the process of reproductionb) plants need to respond to changes in the environment to best meet their needs.c) because it is a way that plants directly compete with each other for their resources

■ ______________________ is growth or movement of a plant that responds to a ______________ stimulus

■ Cells on a plant have a hormone called auxin that cause the plant to have _________________ cells on the side of the plant that doesn’t have light so it can stretch to get more light.

■ _______________-growth or movement of a plant in response to ________________.

– Roots __________ in the direction of gravity

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Name: __________________________________ Date: __________________ Period: ________

– Stems grow _______________ the direction of gravity

■_________________

the growth or movement of a plant in response to

_________________.

________________ is growth or movement of a plant in response to touch.

■ The Venus flytrap, or Dionaea muscipula is a plant that exhibits this characteristic.

– Sometimes called “Piranha Plants” because it bites down on unsuspecting prey like insects and ____________ them for food.

– The Venus flytrap is _________ an autotroph and heterotroph known as a ‘Mixtroph’. There are several other examples in nature, most are protists.

Independent Practice1. Plants twisting around a wire support is an example of

A. turgor pressureB. hydrotropism C. thigmotropism

D. phototropismE. gravitropism

2. This diagram below shows two germinating corn seeds that have been placed in identical bottles and kept in the dark.

Bottle A will be rotated 90 degrees each day for the next 6 days. Bottle B will not be rotated.

Which hypothesis is most likely being tested in this experiment?

A. The amount of light received affects

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Name: __________________________________ Date: __________________ Period: ________

chlorophyll production.B. Water is need for proper plant growth.C. Gravity affects plant growth.D. Enzymes promote seed development.

3. This diagram is an example of

A. turgor pressureB. thigmotropismC. geotropismD. phototropismE. hydrotropism

Where are the stomata located on a water lily, and why would this be an adaptation for an aquatic environment? (think about the function of the stomata.)

• The stomata would be located in a high concentration at the _______________ of the leaf to be able to exchange water,_____ and _____. If the stomata was under the leaf, ____ ____________ would be able to occur.

Seed Dispersal

Some seeds like the Norway maple have adapted to very windy conditions by evolving _______ seed structure so it can travel long ____________.

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Name: __________________________________ Date: __________________ Period: ________

Water Regulation - Before we start to write a CER, lets first identify the functions or definitions of the following 3 terms in your own words.

Stomata - _______________________________________________________________________

Cuticle - _______________________________________________________________________

Transpiration - _______________________________________________________________________

Using the graphs and analyze the information to answer the questions below.

More CLOSED stomata than OPEN stomata.

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

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Answer these questions in a CER format.

A) Make a claim about which plant species is better adapted for a desert environment.

B) Use evidence and reasoning to support your answer.

Name: __________________________________ Date: __________________ Period: ________

Why is having a closed stoma beneficial for water regulation? Be sure to use the word ‘transportation’.

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

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