Transporting Molecules

Outline of the day

1. Turn in your lab reports at the front– More than 10 minutes late = bad

2. Any questions on last week’s lab?

3. Quiz

4. Introduction to the lab

5. Lab!

6. Check out• Get a stamp• Make sure I mark you down for attendance

Quiz

• Ends 8 minutes after it’s started

– Ends at: ____

Lab this week!

• Exploring transportation!– Plants

• Xylem, phloem, etc.

– Animals• Open vs. closed circulatory systems

– Class experiment!• Effect of ______ on recovery from exercise

– Yes, we’ll be exercising!

Water transport in vascular plants

• Water is absorbed by roots

• Travels through stems to leaves, fruits, flowers, etc.

Pinus sylvestris (Scotts pine) GDL image from: http://en.wikipedia.org/wiki/Image:PinusSylvestris.jpg

Missing image:Image showing plant roots,

shoots, and leaves with transporting elements

(xylem, phloem) connecting them.

Water travels through xylem

• Xylem cells are dead, hollow tubes

Hardwood pores - cc by a by McKDandy http://en.wikipedia.org/wiki/Image:Hardwood_Pores.jpg

Missing image:Image showing plant roots,

shoots, and leaves with transporting elements

(xylem, phloem) connecting them.

What causes water to move in plants?

• Evaporation of water from the leaves!– Water evaporates from the leaves– Leaf cells replace their lost water

• From the xylem

– Movement of water into leave cells pulls water up xylem

Leaf image from: http://flickr.com/photos/janinehealy/133056572

Missing image:Detailed image showing

water entering roots, moving through xylem, and

then leaving through stomata in leaves.

How does pulling on water work?

• Water molecules hydrogen bond to each other

hydrogen bonding in water - cc by asa by Thomas Splettstoesser http://en.wikipedia.org/wiki/Image:Liquid_water_hydrogen_bond.png

HOO

HO

O

H

O

O

H OO

Missing image:Image showing water

moving up a capillary tube

Animal circulation

Open vs. ClosedCirculatory systems

• Blood in vessels (arteries, capillaries, veins) all of the time

• Blood moves in some vessels– But bathes organs in the body cavity – e.g. Insects have no capillaries or

veins

• No capillaries!

Missing image:Image illustrating an open

circulatory system

Missing image:Image illustrating a closed

circulatory system

Blood vessels:Arteries Veins

Missing image:Image contrasting artery

and vein anatomy

Regulation of blood flow

Capillary bed - PD by US Government from http://en.wikipedia.org/wiki/Image:Illu_capillary.jpg

Examples today:

• Arthropods – open circulatory system– Crayfish (no veins or capillaries)

• Annelids (segmented worms) – closed– Earthworm

• Mollusks - mixed– Clam: open (no veins or capillaries)– Squid: closed

• Vertebrates – closed

Let’s get started!

• In about 10 minutes we’ll discuss the exercise portion of the lab

Today’s experiment!

• In your group, come up with a list of at least four variables that you think might affect recovery from exercise– Write these on page 7-8

• We’ll talk about these as a group in a bit

The variables

• We’re going to choose one to experiment on today

Doing the experiment

• Take your pulse now– Record it in your lab manual

• Jog around the science wing twice!

• When you get back, measure your pulse rate every two minutes– Record the data in the lab manual

Do NOT participate if you have a health condition that prevents you from exercising or if you, for any reason, do not want to participate; there is no need to inform me why you are not participating. Stop exercising if you feel out of breath of experience physical pain. Report any injuries to me.

Before you leave

• Clean up your work area

• Show me your lab report so I can stamp it– Need to have all data fields filled in– Complete at home and then turn in at the beginning of

next lab

• Remember that we’ll have a quiz at the beginning of the next class– 6-7 questions on today’s lab– 3-4 questions on the lab we’ll do next week

Notes for the instructor:• Add any relevant cleanup instructions to the final slide (that slide is

a generic one I’m adding to each presentation).• As it’s difficult to tell open from closed circulatory systems on our

models (e.g., our chordate model doesn’t draw in capillary beds, and thus has blood vessels ending in open holes, as you’d expect an open circulatory system to have), I simply tell the students which organism has each type of system. I do, however, inform them that they must recognize each type of system, even on a different model. If you have better models, I’d suggest not giving them the answers ahead of time.

• I apologize about the high number of missing images; I haven’t been able to find good, license-free, images of this content. If you find any, please let me know!

• Transportation of water in plants can be a difficult topic to introduce; I find that using this animation: http://croptechnology.unl.edu/animationOut.cgi?anim_name=transpiration.swf&width=0&height=0 can help.

License information

• This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.

• The slides in this presentation were originally created by Marc C. Perkins (http://faculty.orangecoastcollege.edu/mperkins).

• You are free to use, modify, and distribute these slides according to the terms of the Creative Commons license (e.g., you must attribute the slides, no commercial uses are allowed, and future distributions must be licensed under a similar license).

• Attribution should be given to Marc C. Perkins (and any later editors), including a link back to Marc’s current website. This applies both while distributing the slides and during use of the slides; attribution during use can be satisfied by, for instance, placing small text on at least one of the slides that has been shown (see below for an example).

Slides in this presentation based on those created by Marc C. Perkins. http://faculty.orangecoastcollege.edu/mperkins

History

• August 2007: Marc Perkins released first version. http://faculty.orangecoastcollege.edu/mperkins

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