SCIENCE APRIL 21, 2016 GERMINATION, DORMANCY, LIMA BEAN LAB

WARM UP  Bring your notebook, pencil, and agenda to your desk  Complete Friday’s warm up now  YOU ARE QUIET, WORKING WHEN THE BELL RINGS!!!

WRITE IN NOTEBOOK  Stimulus (changes) can be positive or negative.  Positive response = movement is toward the stimulus  Negative response = movement is away from the stimulus

Positive and Negative Response  We will now take time to review different scenarios that are both positive and negative

In your notebook…  Find a blank page in your notebook  Draw a line down the center of the page  Label the left column Positive  Label the right column Negative

Positive Phototropism Response  Phototropism: the way a plant grows or bends in response to SUNLIGHT  POSITIVE: Plant stems moving or bending toward the stimulus (the light / sun).

Negative Phototropism Response  Phototropism: the way a plant grows or bends in response to SUNLIGHT  NEGATIVE: Plant roots moving away from the stimulus (the light / sun).

Positive Gravitropism Response  Gravitropism (geotropism): the way a plant grows or bends in response to gravity  Plant structures can sense up and down  POSITIVE: The roots of plants grow down (toward the pull of gravity)

Negative Gravitropism Response  Gravitropism (geotropism): the way a plant grows or bends in response to gravity  Plant structures can sense up and down  NEGATIVE: Stems of plants grow upright (against gravity)

Positive Thigmotropism Response  Thigmotropism: the way a plant grows or bends because of touch (stimulus).  POSITIVE: When a plant touches and wraps around a support / moves toward the structure they are touching

Negative Thigmotropism Response  Thigmotropism: the way a plant grows or bends because of touch (stimulus).  NEGATIVE: When a plant is touched, it may close in an attempt to move away from the stimulus

Positive Hydrotropism Response  Hydrotropism: the way a plant grows due to the presence of water (stimulus).  POSITIVE: When roots sense water, they bend and grow towards it. (for example roots grow towards a creek or stream)

Negative Hydrotropism Response  Hydrotropism: the way a plant grows due to the presence of water (stimulus).  NEGATIVE: When plants’ stems and leaves sense water, they move away from it.

Draw (1 minute)  Draw the tree with roots and stems on your paper  Label the positive tropism for the leaves, branches, stems:  Label the positive tropism for the roots

Draw (1 minute)  Positive phototropism for the stems:  Positive gravitropism for the roots

Moving on…  We will now spend time discussing seed germination and dormancy

What do you think?  Explain germination based on what you see in the picture. Raise you hand to explain!

Write in notebook: Germination : when conditions are right for seeds to start to grow and develop into a new plant

Today’s AGENDA: 1. Review Positive and Negative Tropism 2. Stations around the room (this will consists of you drawing images and writing notes) 3. Lima Bean Lab (if you finish stations)

Next are stations..  Around the room are different stations  You must take your notebook around the room to record the information and make detailed drawings  If you finish this, you will get to complete the lima bean lab

Station 1 “Process of Seed Germination”

Station 1: Process of Seed Germination (copy all information)  Seeds are protected by a tough, hard shell or seed coat.  When seeds are eaten by animals, the seed coat softens  For others, soaking the seed in water will soften the seed coat

Station 2 What do seeds need to germinate?

Station 2  Seeds need the RIGHT conditions to germinate..  They need water  They need sunlight  They need the right temperatures

Station 3 Draw this picture Seed Germination…

Station 4 What does “dormancy” mean?

Station 4  Dormancy means inactivity.  It’s like the seed is in a “sleep- state”  Seeds require a period of DORMANCY before they germinate (grow).

Station 5 Why are seeds dormant?

Station 5:  Seeds become dormant when conditions are not good.  Typically seeds that are dormant are VERY dry.  Seeds can be dormant for YEARS!!!!

Station 6 How do seeds wake up?

Station 6:  What conditions wake up seeds (so they can come out of dormancy)?  moisture  temperature  light  Some seeds need complete darkness to germinate  and in some cases even fire

FUN FACT  Did you know that pinecones can only release seeds from being dormant when they are LIT on FIRE!

Lima Bean Lab

Lima Bean Lab station 7  CONGRATULATIONS!!!  You have recorded all the important information  You will now have time to independently complete a lima bean lab

Lima Bean Lab  Come see me now…..  You will receive a handout detailing the lab along with 2 lima beans

Before dissecting your lima bean, answer these questions in your notebook using complete sentences:  1. What does the dry seed look like?  2. How big is the dry seed? Trace the seed in your notebook.  3. How is the wet seed different from a dry seed?

How to dissect your lima bean: Pull off the seed coat

How to dissect your lima bean: Split the lima bean in 2 (pull away from the indentation)

 What does the split seed look like on the inside?  Explain what you see inside.  Why do you think the bean is SO much bigger than the tiny structure you see inside? Answer these questions in your notebook. Use complete sentences!