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RE: Apologia - 5/11/2009 9:21:16 AM
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rosenon
Posts: 281
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Hi Everyone,
For those of you interested, Dr. Wile now has a blog: Dr. Wile's Blog. He has posted some GREAT information and articles already.
Have fun reading your author's insights.
God Bless,
Steve
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RE: Apologia - 5/16/2009 6:03:33 PM
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rosenon
Posts: 281
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From: Washington State
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Hi Everyone,
For those of you finishing up ECGS Module 16, I though maybe this little vignette and a web site might help:
The nervous system is a network of specialized cells that transit information about an organism's surroundings and itself. It processes this information and causes reactions in other parts of the body, which is what allows us to move, eat, sleep, etc. The nervous system is composed of neurons and other specialized cells called neuroglia, that aid in the function of the neurons. The nervous system is divided broadly into two categories: the peripheral nervous system (PNS) and the central nervous system (CNS). Neurons generate and conduct impulses between and within the two systems. The peripheral nervous system is composed of sensory neurons and the neurons that connect them to the nerve cord, spinal cord, and brain, which make up the central nervous system. In response to stimuli, sensory neurons generate signals to the central nervous system which then processes and conducts signals back to the muscles and endocrine glands. The neurons of the nervous systems of animals are interconnected and use electrochemical signals and neurotransmitters to transmit impulses from one neuron to the next. The interaction of the different neurons form neural circuits, which regulate an organism's perception of the world and what is going on within its body.. Nervous systems are found in many multicellular animals but differ greatly in complexity between different members of God's Creation.
Check this site out. I am sure you will find it fascinating:
http://faculty.washington.edu/chudler/introb.html
It has been a pleasure serving you this school year. Please keep in touch over summer.
God Bless,
Steve
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RE: Apologia - 6/4/2009 12:27:55 AM
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rosenon
Posts: 281
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From: Washington State
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Hi Everyone,
Just want to give you an update on the RWT/Apologia DVD series for PC and Mac. You were all so GREAT at giving us feedback regarding the program that I wanted you all to be the first to know that the first four courses in the series have been completed. Thanks again for helping us serve you with good products by providing us super feedback.
I am done teaching for the summer now, but will be working on the DVD chemistry course. I will continue to post vignettes during the summer to help those of you year round schooling. Have a fun summer break :-)
God Bless,
Steve Rosenoff
ApologiaAcademy
Science Instructor
Chief Steward - Red Wagon Tutorials
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RE: Apologia - 6/18/2009 10:13:46 AM
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alegnacb
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Mr. Rosenoff,
Ds#1, who was in your TPS Biology class a couple of years ago, will soon be doing your Marine Science course through Red Wagon Tutorials. Any chance that you'll offer grading of lab reports for an additional fee? My ds does a great job when he's writing them for you, but it's like pulling teeth to get him to write a good informal report for me.
Thanks for teaching ds how to write formal lab reports. His lab report grades for TPS Anatomy & Physiology this past year were great due to your instruction and greatly helped his overall grade.
I'm sure racking up a collection of Apologia books: all of the Young Explorer series, 1st & 2nd editions of General Science and Physical Science, Biology, Chemistry, Adv Biology, and now Marine Biology.
The "Religions Class" link at your website is actually linked to the ALDEA Language Training website.
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Hundreds of alphabetized links to lapbooks on a variety of topics
What is lapbooking? See http://www.squidoo.com/lapbooking .
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RE: Apologia - 6/21/2009 8:58:17 AM
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judii1
Posts: 459
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I was wondering how the kids that use Apologia are scoring on the ACT and SAT?
Someone told me that there is evolution based questions on the tests. How do the kids answer those kind of questions?
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RE: Apologia - 6/22/2009 4:19:10 PM
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rosenon
Posts: 281
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From: Washington State
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quote:
ORIGINAL: alegnacb
Mr. Rosenoff,
Ds#1, who was in your TPS Biology class a couple of years ago, will soon be doing your Marine Science course through Red Wagon Tutorials. Any chance that you'll offer grading of lab reports for an additional fee? My ds does a great job when he's writing them for you, but it's like pulling teeth to get him to write a good informal report for me.
Thanks for teaching ds how to write formal lab reports. His lab report grades for TPS Anatomy & Physiology this past year were great due to your instruction and greatly helped his overall grade.
I'm sure racking up a collection of Apologia books: all of the Young Explorer series, 1st & 2nd editions of General Science and Physical Science, Biology, Chemistry, Adv Biology, and now Marine Biology.
The "Religions Class" link at your website is actually linked to the ALDEA Language Training website.
Thanks so much for this word of praise. I am so glad your student did so well in TPS A&P. He certainly had to put forth lots of effort to pass Sally's class.
The RWT recorded program and DVD program is designed to allow for more student independence and less teacher direction. They never were designed to replace the TPS or ApologiaAcademy live-feed, more structured programs. Subsequently, the recorded program uses a different format, direction, and price scale. The fee I would need to charge to make lab report grading a reality for RWT would make the price of the course prohibitive and comparable to the TPS/AA live-feed courses. Basically, an RWT recorded class would need to carry the same cost as a TPS or an ApologiaAcademy live-feed to make RWT lab report grading profitable. If you need lab report grading, the better choice would, therefore, be the TPS or ApologiaAcademy live-feed programs, as you get all the benefits of attending the Academy class.
By the way, I will be posting a video on how to prepare a formal lab report on my web site later this summer. I will post the link to it here in this forum also so that you all can view it free of charge.
The same person who teaches the ALDEA language classes also teaches the "Religions Class," which is why the link directs you to ALDEA.
Hope that helps.
Steve
< Message edited by rosenon -- 6/22/2009 4:34:36 PM >
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RE: Apologia - 7/4/2009 12:40:55 PM
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rosenon
Posts: 281
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From: Washington State
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Hi Everyone,
I just found out this week that Apologia Academy (www.apologiaacademy.com) is going to offer its apologetics and science courses to adults this next September. The idea is to help parents and co-op teachers teach their kids science. We are still working out the details, but I thought you all might like to know about this exciting opportunity.
God Bless,
Steve
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RE: Apologia - 7/6/2009 11:38:53 AM
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sln613
Posts: 1
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Hi Steve,
I just found this board and find it extremely helpful. I have a question about Apologia and taking AP exams. I have reviewed an earlier discussion from 2008 but not found the answer to my specific question (though it did address AP Biology very well). My DD has been using Apologia for 3 years - Apologia General Science (7th grade), Physical Science (8th grade) and Chemistry (9th grade - labs and review done in co-op). She liked chemistry very much and this fall (10th grade) she is interested in doing Apologia Advanced Chemistry (again in co-op for review and labs) and concurrently Apologia Biology (in co-op for review and labs). She would like to take the AP Chemistry exam at the end of the year (May 2010). My question is, what else do you believe she would need to do to prepare her for this exam? Princeton Review? Or are there additional Apologia courses she would also need to have had?
Thanks for your time.
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RE: Apologia - 7/6/2009 10:14:40 PM
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rosenon
Posts: 281
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From: Washington State
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quote:
ORIGINAL: sln613
Hi Steve,
I just found this board and find it extremely helpful. I have a question about Apologia and taking AP exams. I have reviewed an earlier discussion from 2008 but not found the answer to my specific question (though it did address AP Biology very well). My DD has been using Apologia for 3 years - Apologia General Science (7th grade), Physical Science (8th grade) and Chemistry (9th grade - labs and review done in co-op). She liked chemistry very much and this fall (10th grade) she is interested in doing Apologia Advanced Chemistry (again in co-op for review and labs) and concurrently Apologia Biology (in co-op for review and labs). She would like to take the AP Chemistry exam at the end of the year (May 2010). My question is, what else do you believe she would need to do to prepare her for this exam? Princeton Review? Or are there additional Apologia courses she would also need to have had?
Thanks for your time.
The Princeton Review would be an excellent choice. Because I don't see Physics in your student's resume, I would hit the sections dealing with thermodynamics and physical chemistry particularly hard. I would also spend lots of time on AP Central:
http://apcentral.collegeboard.com/apc/public/courses/teachers_corner/2119.html
The teacher's page has some wonderful helps for the Exam. There are pages like this for all the AP Exams available. I would pay close attention to the lab essay questions. I have my students write formal lab reports to help them develop analytical thinking about their science work. Doing the experiments is not enough. You need to follow the process of hypothesis, observation, analysis, and conclusion in a formal paper to really prepare for the Exam well. There are formal report examples linked to my course pages on my web site:
http://www.redwagontutorials.com/
Click on the link for "Live-Feed" course information, then on the "Chemistry" link, and finally, the link to the "Formal Report."
Hope that helps.
God Bless,
Steve
< Message edited by rosenon -- 7/7/2009 10:09:02 PM >
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RE: Apologia - 7/17/2009 9:18:25 AM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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Hi Everyone,
WOW, lots of e-mails from you Physical Science folks asking if I can post the links for your class also. For those of you starting ECPS this fall, here are the links to my first class in September:
Physical Science: Module 1
Video Lectures:
Module 1, Part 1
Module 1, Part 2
Class Notes:
Module 1, Part 1
Module 1, Part 2
Formal Lab Report:
Experiment Report
Test Review:
Module Review
Module Test & Answers:
Module Test
Module Test Answers
I have also posted my 2009-2010 Course Schedule on my Physical Science page:
http://www.redwagontutorials.com/WelcomeP.html
You are welcome to use these to help you structure your year. The recordings currently posted are from last year, but I will be uploading a new edition September 7th. You are welcome to use these links to listen in on our first day.
God Bless,
Steve
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RE: Apologia - 7/29/2009 5:39:41 PM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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Hi Everyone,
Okay, Okay, you'd think I was giving away gold here :-) For you folks starting biology, here are the links:
Biology: Module 1
Video Lectures:
Module 1, Part 1
Module 1, Part 2
Class Notes:
Module 1, Part 1
Module 1, Part 2
Formal Lab Report:
Experiment Report
Test Review:
Module Review
Module Test & Answers:
Module Test
Module Test Answers
I have also posted my 2009-2010 Course Schedule on my Biology page:
http://www.redwagontutorials.com/WelcomeB.html
You are welcome to use these to help you structure your year. The recordings currently posted are from last year, but I will be uploading a new edition the week of September 7th. You are welcome to use these links to listen in on our first day.
God Bless,
Steve
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RE: Apologia - 8/10/2009 12:37:39 AM
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dehartfam
Posts: 1
Joined: 8/10/2009
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I have a question I am hoping you can help me with. We used all of the apologia sciences by Jeannie Fulbright and throughly enjoyed them. When my daughter went into 7th grade we purchased the online version of General Science - it was terribly hard for her so we set it aside and I tried it again last year. I found it to be alot of reading and difficult on the computer because you could not highlight points, go back and look something up etc. We did not complete it and I did something different. The year she enters the 9th grade - my son is going in the 7th. I would like to do the Apologia Physical Science with them both. I am not sure if it will count as a high school science credit for her and I need to know if they can do the Physical Science without having done the General Science. Does anyone know? The reviews I have read on line seem to be unanimous that the General Science is just tedious and laborious. Any suggestions would be helpful. My daughter will just now be doing prealgebra for her math as this is her hardest subject. My son is basically on track for his grade. THanks in advance!
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RE: Apologia - 8/10/2009 8:56:55 AM
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2jsmom
Posts: 925
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You could do physical science without doing general science, it's not a prerequisite. As far as counting physical science as a high school course, I've been told that it qualifies, and I know many people, including myself, who are counting it.
You mentioned that it was harder for your daughter to do the lessons on the computer. I think that's a valid concern. My son loved the computer version, he liked having all the resources at a click of a button and being able to make the page larger. I found it much harder to read. We went with the computer version since that's what worked for him, but if I was the student, I would have wanted the actual book. Perhaps you could find a used book for her to work from?
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RE: Apologia - 8/25/2009 7:44:43 PM
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judii1
Posts: 459
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From: The Frozen Thumb of MI!
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Most high schools teach physical science in 9th grade.
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RE: Apologia - 9/6/2009 6:31:37 PM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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Sorry folks, but my computer crashed and I have been busy restoring my favorites. I forgot to add Crosswalk.com back into my favorites list until this morning.
You all are exactly correct. Physical Science is usually a 9th-grade, high school, science course in most public school districts. You should be able to get science elective credit for the class. The reason Apologia calls it an 8th-grade course is we feel that home schooled children are on a more advanced track. Dr. Wile backed up each science year to accommodate your very bright students. Before you ask, "Yes, General Science would normally be taught in 8th-grade in the public school setting." You cannot get high school credit for General Science. When I taught public middle school here in Washington State, the eighth-grade curriculum I used was VERY similar to Apologia's ECGS, without all the Christian perspective, of course.
Hope that helps,
Steve
< Message edited by rosenon -- 9/6/2009 10:55:43 PM >
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RE: Apologia - 9/9/2009 3:36:40 PM
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allisonbrett
Posts: 87
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From: A bit north of the Big Chicken
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This is SO true!!! We got General Science for my 7th grader last year. She was so overwhelmed as it seemed very advanced. We stuck with it and modified only slightly. She got the hang of it and did quite well by the end of 7th grade.
She wanted to try something else for 8th grade so we ordered another program. We both found after a month that we needed to go back to Apologia. We've ordered it and are ready to get back on track!
We discovered that in comparison with other programs Apologia was much easier to understand despite it's advanced concepts and material. But this also puts her ahead of the game. We're tenatively planning on 9th grade Biology, 10th Marine Biology 11th - Chemistry and who knows for 12th. Probably won't do Physics. She's not really math/science geared and at this point is not thinking college. I hope that will change.
Anyone know, will Apologia create other high school programs? (i.e. Anatomy, Zoology, Botany)
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A work in progress so please be patient, God is still working on me. Ouch, it sure is painful!
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RE: Apologia - 9/11/2009 12:29:10 AM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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A good fit for your student is the Advanced Biology curriculum: The Human Body, Fearfully and Wonderfully Made. If you follow your planned course sequence and top it off with the above book, your student will be set to take the SAT II Biology, CLEP Biology, and/or National AP Biology placement exams. If she does end up going to college, passing any of these tests could get her some college credit.
Zoology and Botany are usually sophomore year of college courses. There are a few high school curriculums out there, but Zoology and Botany will not prepare your student for the national exams the way Advanced Biology will. Apologia has no plans at this time to produce a high school Zoology or Botany book at present that I know of.
Hope that helps.
God Bless,
Steve Rosenoff
Online Science Instructor
ApologiaAcademy
www.apologiaacademy.com
www.redwagontutorials.com
< Message edited by rosenon -- 9/12/2009 8:23:06 PM >
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RE: Apologia - 9/29/2009 1:13:20 PM
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allisonbrett
Posts: 87
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From: A bit north of the Big Chicken
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Sounds great, thanks! Advanced Biology sounds like a good option.
Though we are starting a bit late in physical science this year I found that my dd is moving through quite well. Sad to have wasted almost 2 months attempting to use something else. I think we're sticking to Apologia.
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A work in progress so please be patient, God is still working on me. Ouch, it sure is painful!
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RE: Apologia - 10/3/2009 1:56:28 PM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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Hi Everyone,
For you folks starting chemistry, here are the Module 1 links:
Chemistry: Module 1
Video Lectures:
Module 1, Part 1
Module 1, Part 2
Class Notes:
Module 1, Part 1
Module 1, Part 2
Formal Lab Report:
Experiment Report
Test Review:
Module Review
Module Test & Answers:
Module Test
Module Test Answers
I have also posted my 2009-2010 Course Schedule on my Chemistry page:
http://www.redwagontutorials.com/WelcomeC.html
You are welcome to use these to help you structure your year. The recordings currently posted are from this September. You are welcome to use these links to listen in on our first day.
Red Wagon Tutorials is also now offering online testing and grading support for many of the Apologia courses to the general public. Please see the RWT web site for course testing/grading availability.
God Bless,
Steve
< Message edited by rosenon -- 10/4/2009 8:22:03 PM >
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RE: Apologia - 10/26/2009 11:59:47 PM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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Hi Everyone,
I so appreciate all the notes from parents who have viewed the posted class threads. I am so glad I could be of service to you at the beginning of your school year. I will be posting further course vignettes soon, but right now I recovering from the flu. Keeping watching this thread for more helpful tidbits.
God Bless,
Steve
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RE: Apologia - 11/21/2009 7:46:37 PM
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rosenon
Posts: 281
Joined: 11/28/2007
From: Washington State
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Hi Everyone,
For those of you starting Module 6 of ECB, here is a GREAT summary of all the cell organelles and their functions. Enjoy, and Happy Thanksgiving!
God Bless,
Steve
PLASMA MEMBRANE:
http://micro.magnet.fsu.edu/cells/plasmamembrane/plasmamembrane.html
The plasma membrane is semi-permeable. It allows certain substances (nutrients, water, and oxygen, for example) to pass through and enter the cell, but it does not allow other substances (certain toxins, for example) in. Likewise, the plasma membrane allows water and waste products to leave the cell, but it does not allow the contents of the cell itself to leave.
CYTOPLASM:
http://micro.magnet.fsu.edu/cells/animalcell.html
Cytoplasm is a jelly-like fluid in which all of the cell organelles are suspended. The cytoplasm is comprised of a mixture of several different compounds, including proteins, fats, and carbohydrates. In addition, there are substances called ions in the cytoplasm.
As you already learned, atoms must have the same number of protons and electrons in order to remain electrically balanced. Well, if an atom loses or gains an electron, it suddenly is thrown out of electrical balance. If it gains electrons (which are negatively charged), it ends up with an overall negative charge, and if it loses electrons, it ends up with an overall positive charge. Once this happens, it ceases to be an atom and is called an ion. Since ions have electrical charge, they respond to electrical stimuli.
MITOCHONDRION:
http://micro.magnet.fsu.edu/cells/mitochondria/mitochondria.html
Perhaps the most important of the organelles are the mitochondria, which is the plural of mitochondrion. These bean-shaped organelles are often referred to as the “powerhouses of the cell,” because they are responsible for the respiration of monosaccharides which releases energy that can be used by the cell.
LYSOSOME:
http://micro.magnet.fsu.edu/cells/lysosomes/lysosomes.html
Remember, in order to use polysaccharides or disaccharides, a cell must first break them down into monosaccharides using hydrolysis reactions. In addition, cells must break certain proteins and lipids down into their constituent parts (amino acids and fatty acids, respectively) in order to use them for biosynthesis. All of the necessary hydrolysis reactions take place in the lysosome.
Interestingly enough, when the lysosome was first discovered, it was called the “suicide sac” because prior to the death of certain cells, the lysosomes would release chemicals that destroyed the cell. Later on, scientists realized that as the cell dies, the membrane which encloses the lysosome is generally the first thing to deteriorate. When that membrane deteriorates, the contents of the lysosome spill into the cytoplasm of the cell.
Some cells, such as white blood cells, actually use their lysosomes to commit suicide. A white blood cell tries to kill invading pathogens. One way it can do that is to fill itself with a huge amount of antibodies. Then, it can enter into a group of pathogens and rupture its own lysosomes. This will cause the cell to break open, and the antibiotic will spill out onto the pathogens, killing them. Thus, the white blood cell runs a “suicide mission” to destroy the pathogens. When you have an infected cut, the pus is actually the remains of the white blood cells after their suicide runs!
RIBOSOMES:
http://micro.magnet.fsu.edu/cells/ribosomes/ribosomes.html
The ribosomes are non-membrane bound organelles that are found in both eukaryotic and prokaryotic cells. These organelles are responsible for production of proteins in the cell.
ENDOPLASMIC RETICULUM:
http://micro.magnet.fsu.edu/cells/endoplasmicreticulum/endoplasmicreticulum.html
The endoplasmic reticulum, commonly abbreviated as ER, is composed of an extensive network of folded membranes. There are two types of ER, rough ER and smooth ER. Rough ER is dotted with ribosomes, smooth ER is not.
Since it has ribosomes, rough ER is a part of protein synthesis. Typically, specialized proteins that are secreted by certain cells are produced here. Although no protein synthesis occurs in smooth ER, many cells produce lipids in this organelle. These lipids are generally the means by which excess energy is stored. In addition, smooth ER inactivates certain harmful by-products of digestion and respiration and then sends them to the plasma membrane to be ejected.
GOLGI BODIES:
http://micro.magnet.fsu.edu/cells/golgi/golgiapparatus.html
Golgi bodies are comprised of flattened, interconnected membrane sacs that store proteins and lipids. When the cell produces proteins and lipids, they are transferred to the Golgi bodies where they are sorted and stored until needed. When a protein or lipid is needed by the cell, the Golgi bodies package the molecule so that it can be transported to the place in which it is needed. The “packaging” that goes on in the Golgi bodies is typically some process of adding a small molecule to the protein or lipid that is being processed. This chemical then can be used by the cell as a marker, telling the cell where to transport the molecule. Thus, the Golgi bodies function much like a mailing service. They take in molecules, package and address them, and then send them to where they are needed.
VACUOLES:
http://micro.magnet.fsu.edu/cells/endosomes/endosomes.html
Vacuoles are “sacs” that exist in the cell. You already know about food vacuoles and contractile vacuoles. Those are both present in animal cells. In addition, there are waste vacuoles that hold waste and phagocytic vacuoles that can be used to engulf things. If a vacuole is small, it can be called a VESICLE. A pinocytic vesicle is one that is formed so that proteins can be absorbed. A secretion vesicles is used to take chemicals made by the cell and send them out of the cell for other cells to use (secretion).
There is another type of vacuole that is only present in plant cells. I will cover that in a moment.
CENTRIOLES:
http://micro.magnet.fsu.edu/cells/centrioles/centrioles.html
Centrioles are interesting organelles that have two rather different functions. In cells that possess flagella (euglena, for example) or cilia (paramecia, for example), the centrioles actually form the base of the movement organelle.
Centrioles have a completely different function as well. In many eukaryotic cells, centrioles appear in pairs. Each individual centriole is oriented at a 90 degree angle to its partner, like the corner of a square. These centrioles are necessary for reproduction. You will see how that happens later, when we discuss mitosis and meiosis in Module #7.
NUCLEUS:
http://micro.magnet.fsu.edu/cells/nucleus/nucleus.html
As you already know, the nucleus contains the DNA. During most of the cells life, the DNA is referred to as CHROMATIN. During the reproduction of the cell, the DNA winds itself up into chromosomes. You will learn more about that in Module #7. When rolled up into chromosomes, the DNA is referred to as chromosomes, not chromatin.
The nucleus has its own membrane to keep certain chemicals out and let other ones in. In addition, there is a nucleolus that holds RNA. We will discuss that more in Module #7 as well.
CYTOSKELETON:
Cytoskeleton is a network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement. The cytoskeleton is made up of three basic kinds of fibers: microfilaments, intermediate filaments, and microtubules. You already learned about microtubules when we discussed the centrioles, but the other two types of filaments are new to you. Microfilaments are fine, threadlike proteins found in the cell's cytoskeleton. Intermediate filaments are threadlike proteins in the cell's cytoskeleton that are roughly twice as thick as microfilaments
Each of these types of fibers makes its own contribution to the cytoskeleton.
http://micro.magnet.fsu.edu/cells/microfilaments/microfilaments.html
The microfilaments are mostly associated with movement. For example, microfilaments are responsible for the ponderous motion exhibited by amoeba. They also can cause certain cells to contract. Muscle cells, for example, do their job by contracting and relaxing. The microfilaments in the muscle cells take care of this function. Finally, in some cells, the microfilaments also generate cytoplasmic streaming.
http://micro.magnet.fsu.edu/cells/microtubules/microtubules.html
Microtubules also participate in cell movement. As you have already learned, they are used to form cilia and flagella in the cells that have those structures. They also provide a “track” upon which organelles and vesicles can travel as they move throughout the cell.
http://micro.magnet.fsu.edu/cells/intermediatefilaments/intermediatefilaments.html
The intermediate filaments are mostly responsible for strengthening and supporting the cell, which allows it to keep its shape. Another important role of the cytoskeleton is to keep the various organelles of the cell in their proper positions. Cellular organelles are not free to “float around” the cell, because the internal cellular structure is just too complex to allow for that. Thus, the cytoskeleton holds this complex structure together by keeping each organelle in its proper position.
The makeup of an individual cell's cytoskeleton is characteristic of the task for which the cell has been designed. For example, skin cells must be very rigid. As a result, the cytoskeleton of a skin cell contains a lot of intermediate filaments so that it can hold its shape well. A muscle cell does a lot of contracting and relaxing, so it has a lot of microfilaments in its cytoskeleton. A paramecium needs lots of cilia, so it has a high concentration of microtubules. Although you might not think about it, there are cells in your body that have cilia as well. The bronchial tubes that bring air to your lungs are lined with cells that have cilia. These cilia filter dust and debris from the air that you breathe and then beat back and forth to sweep the dust and debris away from your lungs.
PLANT CELL:
http://micro.magnet.fsu.edu/cells/plantcell.html
This is a plant cell. You will notice a few things that are different between a plant cell and an animal cell. First of all, a plant cell tends to be more rectangular while an animal cell is more oval.
CELL WALL:
http://micro.magnet.fsu.edu/cells/plants/cellwall.html
Second, a plant cell has a CELL WALL, while an animal cell does not. The cell wall is typically made of cellulose and pectin, a substance that hardens cellulose. These materials are secreted by organelles in the cell. Although the main function of the cell wall is to protect the cell from its surroundings, the cell wall is full of small holes called pores. These pores allow substances (like nutrients) in its surroundings to diffuse through the cell wall and into the cell. They also allow waste products from the cell to diffuse into the surroundings.
Notice that a plant cell DOES NOT have a lysosome. That’s because plant cells do not take in polysaccharides or make lipids. Thus, it does not need to break those substances down.
PLASTIDS:
http://micro.magnet.fsu.edu/cells/chloroplasts/chloroplasts.html
These organelles are found only in plant cells, some protozoa, and algae. They are not found in animal cells. They are generally grouped into two categories: leucoplasts and chromoplasts. Leucoplasts store starches or oils, while chromoplasts store pigments. When plants have excess monosaccharides from photosynthesis, they are typically linked together in a long polysaccharide called starch. This allows the plant to store them for future use. The leucoplasts are where these starches are stored. Potatoes, for example, are full of starch because that’s where a potato plant has its leucoplast-containing cells.
The chromoplast with which you are most familiar is the chloroplast. This structure contains the pigment chlorophyll, a catalyst for the photosynthesis process.
CENTRAL VACUOLE:
http://micro.magnet.fsu.edu/cells/plants/plantmodel.html
Most plant cells have a central vacuole, which is filled with a concentrated solution of several chemicals. Because of the high concentration of solutes in the solution that fills the central vacuole, water tends to enter the central vacuole by osmosis. This makes the central vacuole bigger and bigger, causing it to push the cytoplasm and all of the organelles against the cell wall. This causes the cell to be pressurized, much like a balloon. This pressure, called turgor pressure, helps keep a plant rigid. When a plant begins to wilt, it is because a lack of water has resulted in a lack of turgor pressure inside the plant’s cells. Fresh lettuce, for example, is crisp because its cells are highly pressurized. As the lettuce gets old, however, it loses water, decreasing the turgor pressure and resulting in wilted leaves.
The turgor pressure allows plants to stand. Without it, they would not be able to be rigid. Fungi do not need turgor pressure in their fruiting bodies or aerial hyphae, as they have chitin. Animal do not need it because they have skeletons.
< Message edited by rosenon -- 11/21/2009 7:54:55 PM >
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