Origin of Eukaryotes

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Yesterday we discussed prokaryotes; their characteristics and examples. Today, we’ll examine the eukaryotic cell and its characteristics. But, before we do, lets take a moment to theorize where Eukaryotes evolved from 1.5 billion years ago.

For today’s warm up, do the “Endosymbiosis” worksheet

Key ← Use it as a resource, not to copy

Then we’ll be taking some time to learn the parts of a Eukaryotic cell. Please watch the YouTube Video or open the PPT in Keynote to complete the “Cell Part Chart” in a paper format or as a PDF.

In our next class, we’ll review the types of cells as well as this chart and the parts of a Eukaryotic cell.

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Osmosis in the Kitchen (Lab)

Today we’ll start section two of Unit 4 discussing Passive transport, or the movement of materials from high concentration to low concentration without the use of energy. There are three types of Passive Transport, all of which are related:

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  1. Diffusion: Movement of ANY material from High to Low concentration
  2. Facilitated Diffusion: Diffusion of large materials that requires a transport protein to move across a membrane.
  3. Osmosis: Diffusion of water across a membrane. In your cells, osmosis is a type of facilitated diffusion because it requires Aquaporins to move the water across the cell membrane.

For more information on this process please watch, and take notes on, the video below. When you are finished, please complete Directions of Osmosis Table (PDF) & the Passive Transport Review Questions (PDF).

Catch Up with Cells

This is you playing catch-up obviously

After you Finish your Unit 2 test, we’re going to play a little catch-up with Unit 3… Cells.

Watch the video (or Click the link) below to be taken to our Unit 3-Section 1 Notes on the cell theory. Your assignment is to take these notes tonight and be prepared to discuss and answer questions on it tomorrow! Good luck!

YouTube – Cell Theory

Origin of Eukaryotes

3pxff (1)

Yesterday we discussed prokaryotes; their characteristics and examples. Today, we’ll examine the eukaryotic cell and its characteristics. But, before we do, lets take a moment to theorize where Eukaryotes evolved from 1.5 billion years ago.

For today’s warm up, do the “Endosymbiosis” worksheet (pg.41 in yesterday’s packet)

Key ← Use it as a resource, not to copy

Then we’ll be taking some time to learn the parts of a Eukaryotic cell. Please watch the YouTube Video or open the PPT in Keynote to complete the “Cell Part Chart” in a paper format or as a PDF.

Tomorrow, we’ll review the types of cells as well as this chart and the parts of a Eukaryotic cell.

MEiosis and MItosis… what’s the difference?

Mitosis vs. Meiosis

“So what’s different about Mitosis versus Meiosis?”

 

Well looking at the picture we see Mitosis on the left… There is a single cell, which duplicates its chromosomes, divides, and the result are two cells identical to the parent cell.

Meiosis, on the right, all those same steps occur… BUT THEN! Another cell division occurs! We do PMAT a second Time (Thats Cray-Cray Mr. K)! The result then are 4 cells, with half the number of chromosomes, and each one has a unique set of chromosomes.

I know what you’re thinking… “But why would we only need half the number of chromosomes? Doesn’t each one of the cells of our body need all 46 chromosomes!?”

It is true that each one of our Somatic, or Body, cells needs a complete set of chromosomes. But our Gametes, or Sex Cells, only need half the number of chromosomes. This is known as being Haploid, or having one set of chromosomes. And I bet you already know why! That’s right, the other half comes from the 2nd parent during sexual reproduction (That’s off the chain Mr. K). When the male and female gametes meet (Fertilization), they combine to form one new cell called a Zygote that has two sets of chromosomes, one from Mom and one from Dad. This is known as being Diploid.

Crossing Over

The Red X and the Blue X are duplicated chromosomes. During Prophase 1, they sometimes “Switch Legs”. This is known as Crossing Over.

The coolest part about the whole process is that it makes you Unique. And not in the Sesame Street, “You are special,” kind of way. More like, there are more than 8 million different genetic combinations that you can create in each of your gametes and they are assorted completely randomly (Independent Assortment), meaning that for each of your 23 pairs, you can give either one of the chromosomes, its not predetermined! And sometimes, Duplicated Chromosomes will even switch pieces (Crossing Over) making them even more unique!

All in all, Meiosis is a pretty unique process and I hope you enjoy learing about it as much as I enjoy teaching it! To learn more about Meiosis and how it causes genetic variation, check out my YouTube video below!

Unit 3 Post-Test: So what do you know NOW?

Click the link below to prove how much you have learned about Cells…

Unit 3: What do you think you already know

Reminders: Your Biology – Unit 3 Test is tomorrow! It will cover the following topics:

  • Cell Theory
  • Scientists who contributed
  • Types of cells (compare/contrast)
  • Cell Parts
  • Protein creation

Hopefully later today I’ll begin to post the projects you’ve created to YouTube and to this site. Feel free to come back and see what a great job you did.

Mitosis Vs. Meiosis

“So what’s different about Mitosis versus Meiosis?”

 Well looking at the picture we see Mitosis on the left… There is a single cell, which duplicates its chromosomes, divides, and the result are two cells identical to the parent cell.

Meiosis, on the right, all those same steps occur… BUT THEN! Another cell division occurs! We do PMAT a second Time (Thats Cray-Cray Mr. K)! The result then are 4 cells, with half the number of chromosomes, and each one has a unique set of chromosomes.

I know what you’re thinking… “But why would we only need half the number of chromosomes? Doesn’t each one of the cells of our body need all 46 chromosomes!?”

It is true that each one of our Somatic, or Body, cells needs a complete set of chromosomes. But our Gametes, or Sex Cells, only need half the number of chromosomes. This is known as being Haploid, or having one set of chromosomes. And I bet you already know why! That’s right, the other half comes from the 2nd parent during sexual reproduction (That’s off the chain Mr. K). When the male and female gametes meet (Fertilization), they combine to form one new cell called a Zygote that has two sets of chromosomes, one from Mom and one from Dad. This is known as being Diploid.

The Red X and the Blue X are duplicated chromosomes. During Prophase 1, they sometimes “Switch Legs”. This is known as Crossing Over.

The coolest part about the whole process is that it makes you Unique. And not in the Sesame Street, “You are special,” kind of way. More like, there are more than 8 million different genetic combinations that you can create in each of your gametes and they are assorted completely randomly (Independent Assortment), meaning that for each of your 23 pairs, you can give either one of the chromosomes, its not predetermined! And sometimes, Duplicated Chromosomes will even switch pieces (Crossing Over) making them even more unique!

All in all, Meiosis is a pretty unique process and I hope you enjoy learing about it as much as I enjoy teaching it!

Unit 3 Post-Test: So what do you know NOW?

Click the link below to be swept back in time to the day you took the Unit 3 PreTest. I’d like you to retake the quiz and see how far you’ve come and what you have learned:

Unit 3: What do you think you already know

Reminders: Your Biology – Unit 3 Test is tomorrow! It will cover the following topics:

  • Cell Theory
  • Scientists who contributed
  • Types of cells (compare/contrast)
  • Cell Parts
  • Protein creation

Later today I’ll begin to post the projects you’ve created to YouTube and to this site. Feel free to come back and see what a great job you did.