Standards: 7.LS1.2 Conduct an investigation to demonstrate how the cell membrane maintains homeostasis through the process of passive transport. 

Concentration Gradients

Cells have a pretty sophisticated cell membrane, which acts as a barrier to the outside world. We've described this membrane as selectively permeable, meaning not just anything can get through it. The key to this phrase is that the cell membrane is selective, but not impermeable. This is something like how you would keep your home. The walls of your house create a boundary and define the space, but there are still doors and there are windows through which you can let in your friends or some fresh air on a summer's day.

So what crosses a cell membrane and why? There are several types of ways to transport things across a cell membrane. When and how things travel depends largely on the concentration of solutes in your cells, or the dissolved molecules. In this lesson, we'll discuss methods of transporting solutes across a concentration gradient.

A concentration gradient is a gradual difference in solute concentration between two areas. In this case, it's the difference in solute concentration between the outside of the cell and the inside of the cell. Solutes here would move by diffusion, or movement from a higher concentration of solutes to a lower concentration of solutes in order to equalize solute concentration. This evens out the concentration on both sides.

This is like what happens when you leave the windows of your house open while your neighbor is having a barbeque. The smell might diffuse from next door, where the smell is stronger in the air, into your house, where, unfortunately, there are no hamburgers on the grill. Diffusion occurs until the inside of your house smells like the outside.

READING MATERIAL-LINK 

Passive Transport: Simple Diffusion

Diffusion across a cell membrane is a type of passive transport, or transport across the cell membrane that does not require energy. Remember that the cell membrane is a phospholipid bilayer. Although the inside and the outside of a cell are both water-based, there is a hydrophobic region in the middle, and this is an important barrier to anything large, charged, or hydrophilic. Molecules that are hydrophobic, just like the hydrophobic region, can pass through the cell membrane by simple diffusion.

Therefore, simple diffusion is the unassisted passage of small, hydrophobic, nonpolar molecules from higher concentration to a lower concentration. Very small molecules can slip through the cell membrane, too, even if they are hydrophilic - just like a few ants might crawl through a crack in the wall just because they're tiny.

Define concentration gradient, passive transport, diffusion

Activity 2A. Watch Brain Pop: Passive transport and write five questions of your own https://www.brainpop.com/science/cellularlifeandgenetics/passivetransport/

Activity 2B- https://www.youtube.com/watch?v=Ptmlvtei8hw&feature=youtu.be&list=PLwL0Myd7Dk1F0iQPGrjehze3eDpco1eVz

Osmosis

Another big example of passive transport is osmosis. This is a water specific process. Usually, cells are in an environment where there is one concentration of ions outside and one inside. Because concentrations like to be the same, the cell can pump ions in an out to stay alive. Osmosis is the movement of water across the membrane. 

For a cell to survive, ion concentrations need to be the same on both sides of the cell membrane. If the cell does not pump out all of its extra ions to even out the concentrations, the water is going to move in. This can be very bad. The cell can swell up and explode. The classic example of this type of swelling happens when red blood cells are placed in water. The water rushes in to the cells, they expand and eventually rupture (POP!). 

Activity 3. egg lab

Activity 4. Short animation http://www.sumanasinc.com/webcontent/animations/content/diffusion.html

Activity 5. Online Lab

Day 2

Facilitating Diffusion

So how do large, charged, or hydrophilic molecules pass through the cell membrane if they can't simply just diffuse in? Think of how your friends come into your house. Under most circumstances, they'll use a door. A package delivered at your residence would come through your door, too, but it would need someone to carry it in. A fly might come through an open window on its own, while a squirrel could come down your chimney! There are different types of passageways into the cell just like there are different ways to get into your home, depending on who or what is trying to get through. Each method of passage through the cell membrane might be useful to different molecules.

Facilitated diffusion is passive transport that uses integral membrane proteins to help larger, charged, hydrophilic, and polar molecules across a concentration gradient. Remember that integral membrane proteins span the phospholipid bilayer, connecting the inside and the outside of the cell.

There are two types of integral membrane proteins that help transport molecules, like ions and polar molecules, that can't diffuse on their own through the hydrophobic layer. The first are carrier proteins, which are proteins that bind a molecule to facilitate transport through a cell membrane. The second are channel proteins, which are proteins that create a passageway to transport molecules and ions through the cell membrane. This channel protein creates a pore through the hydrophobic region that allows polar molecules to just pass right through.

http://www.biology4kids.com/files/cell2_passivetran.html 

Active transport:

Active transport process is the movement of a substance against the concentration gradient. Thus, this is an important process in biology that requires energy. In most cells, this is usually concerned with accumulating high concentrations of molecules in the cell which it needs, like ions, glucose, amino acids, etc. Active transport involves the transportation of substances from a region of its lower concentration to a regions of its higher concentration.

Activity 1 Watch Brain Pop Active Transport and write five of your own questions. https://www.brainpop.com/science/cellularlifeandgenetics/activetransport/

Activity 1: Play Dough Lab. 

Write cards for active transport, endocytosis, exocytosis, 

Standards: 7.LS1.9 Construct a scientific explanation based on compiled evidence for the processes of photosynthesis of cellular respiration, and anaerobic respiration in the cycling of matter and flow of energy into and out of organisms. 

Cellular Respiration

Cellular Respiration, process in which cells produce the energy they need to survive. In cellular respiration, cells use oxygen to break down the sugar glucose and store its energy in molecules of adenosine triphosphate (ATP). Cellular respiration is critical for the survival of most organisms because the energy in glucose cannot be used by cells until it is stored in ATP. Cells use ATP to power virtually all of their activities—to grow, divide, replace worn out cell parts, and execute many other tasks. Cellular respiration provides the energy required for an amoeba to glide toward food, the Venus fly trap to capture its prey, or the ballet dancer to execute stunning leaps. Cellular respiration occurs within a cell constantly, day and night, and if it ceases, the cell—and ultimately the organism—dies.

 Two critical ingredients required for cellular respiration are glucose and oxygen. The glucose used in cellular respiration enters cells in a variety of ways. Plants, algae, and certain bacteria make their own glucose through photosynthesis, the process by which plants use light to convert carbon dioxide and water into sugar. Animals obtain glucose by eating plants,or plant products, and fungi and bacteria absorb glucose as they break down the tissues of plants and animals. Regardless of how they obtain it, cells must have a steady supply of glucose so that ATP production is continuous.

 Oxygen is present in the air, and also is found dissolved in water. It either diffuses into cells—as in bacteria, fungi, plants, and many aquatic animals, such as sponges and fish—or it is inhaled—as in more complex animals, including humans. Cellular respiration sometimes is referred to as aerobic respiration, meaning that it occurs in the presence of oxygen.

Cellular respiration transfers about 40 percent of the energy of glucose to ATP. The rest of the energy from glucose is released as heat, which warm-blooded organisms use to maintain body temperature, and cold-blooded organisms release to the atmosphere. Cellular respiration is strikingly efficient compared to other energy conversion processes, such as the burning of gasoline, in which only about 25 percent of the energy is used and about 75 percent is released as heat.

 While most organisms carry out cellular respiration to produce ATP, some cannot produce ATP through this process because they live in anaerobic environments, or environments that lack oxygen. These organisms, typically bacteria, rely on anaerobic processes such as fermentation to generate their ATP.

                             oxygen + glucose= ATP + carbon dioxide + water

                               reactants                      products

Activity 1 Watch the Brain Pop video and write down five notes. Take the Quiz-  https://www.brainpop.com/science/cellularlifeandgenetics/cellularrespiration/ 

Activity 2. Complete the note taking section on your handout. 

Day 4

Photosynthesis

Hey kids.  Are you trying to understand what photosynthesis is?  Here, we'll try and help you!  It is a somewhat simple process that accounts for most of the oxygen in our atmosphere, allowing us to be able to breathe!  We wouldn't ever have existed if it weren't for photosynthesis.  We'll explain it here.

What is Photosynthesis?

Photosynthesis may sound like a big word, but it's actually pretty simple.  You can divide it into two parts:  "Photo" is the Greek word for "Light," and "synthesis," is the Greek word for "putting together," which explains what photosynthesis is.  It is using light to put things together.  You may have noticed that all animals and humans eat food, but plants don't eat anything.  Photosynthesis is how plants eat.  They use this process to make their own food.  Since they don't have to move around to find food, plants can stay in one place. They can make their food anywhere as long as they have three things; carbon dioxide, water, and light.  You have probably heard of carbon dioxide.  It is a chemical that is in the air.  Every time you breathe in, you breath in a bunch of chemicals in the air, including oxygen and carbon dioxide.  Carbon dioxide is also one of the chemicals that causes global warming.  But we'll get to that in a little bit.  Here's what photosynthesis looks like:

Carbon Dioxide + Water + Light ----> Sugar + Oxygen

                                                reactants                        products

Plants breathe, just like us.  They even have little openings that can look like mouths called stomatas, but they are too small for us to see without a microscope.  When we breathe in, we want to breath in oxygen.  Plants want to breathe in carbon dioxide for photosynthesis. Plants also drink.  This is why you need to water plants or they will die.  They use their roots to suck water up into their bodies, and the stomas open up to breath in the carbon dioxide.  Once they have both of these things, all they need is light.  Leaves are made up of a bunch of tiny cells, where this happens.  Inside the cells are tiny little things called chloroplasts.  Chloroplasts are what makes leaves green, and they are also what takes the carbon dioxide, the water, and the light, and turns them into sugar and oxygen.

The sugar is then used by the plants for food, and the oxygen is breathed out into the atmosphere.  This process as a whole is "photosynthesis."

Activity 1: Watch the video and take the quiz

http://studyjams.scholastic.com/studyjams/jams/science/plants/photosynthesis.htm

Activity 2. Write three questions and anwers of your own

Activity 3. Complete the note section on your handout.

Activity 4 Brain Pop : Watch the video and take the quiz https://www.brainpop.com/science/cellularlifeandgenetics/photosynthesis/

 Activity 5. Interactives

http://www.sites.ext.vt.edu/virtualforest/modules/photo.html 

 http://www.pbs.org/wgbh/nova/nature/photosynthesis.html

http://www.eduweb.com/portfolio/studyworks/photosynthesis3b.swf

Lab: Stomata Lab or photosynthesis 

Article review link 

Article review questions:    link

1. What happens to some leaves when it gets cold?

2. What happens to the chlorophyll?

3. What determines the different colors?

Day 5 Standards: 7.LS2.1 Develop a model to depict the cycling of matter, including carbon and oxygen, including the flow of energy among biotic and abiotic parts of an ecosystem. 

The Carbon Cycle

 Carbon is an important element to living things. As we learned earlier, the most abundant substance in organisms is water. The second most abundant substance is carbon. Much of the solid portions of lifeforms is made up of great amounts of carbon.

 How do living things obtain carbon?

 Carbon is extracted from the atmosphere by plants through the process known as photosynthesis. This carbon is combined with other elements in complex ways to form organic molecules important to life. This carbon is later transferred to animals who consume, or eat plants. When plants and animals die, much of their carbon is returned to the atmosphere as the organisms decompose.

Another way carbon is returned to the atmosphere is through cellular respiration. Plants and animals take in oxygen to make energy and breathe out carbon dioxide as a waste product. 

Every so often, a plant or animal does not decompose right away. Their bodies are trapped in locations where decomposition can simply not take place. This is most common at the bottom of oceans and seas where the lifeforms become buried by sand. Instead of returning to the atmosphere, the carbon from these lifeforms is trapped within the Earth. Over millions of years, more and more of the carbon on Earth has been trapped in this manner. Today, almost 99% of all the carbon on Earth has been locked up deep within the Earth. As rocks weather, this carbon is slowly released back into the atmosphere, creating a balance. For the past several hundred million years, the amount of carbon being locked up in the Earth and the amount being released by weathering rocks was almost perfectly balanced. This important balance has been altered significantly in the past century as humans have begun using this trapped carbon also known as fossil fuels to produce energy. Fossil fuels are coal, oil and natural gas. By burning the Earth’s store of carbon, mankind is able to create the energy needed to operate our communities. However, we must be careful as we do so. By releasing more carbon into the atmosphere than is being locked up, we risk causing damage to the delicate carbon cycle.

Another area where carbon is trapped is in the ocean. Carbon is diffused into the water and is used by algae. The ocean is known as a carbon sink because of the amount of carbon taken in. 

Photosynthesis, respiration, decomposition, and combustion are parts of the carbon cycle. 

Note taking sheet for the reading and the game below link 

Activity 1. Carbon cycle game link  

Activity 2- modeling quiz from bioman page 3- click on start a new game then choose the second one down  link 

Activity 3- travel through the carbon cycle dice game- page four  link 

Activity 4- Draw the carbon cycle. You must have the following things in your drawing link 

Video Make me genius https://www.youtube.com/watch?v=xFE9o-c_pKg 

Circle of life video https://www.bing.com/videos/search?q=Carbon+Cycle+Song+The+Lion+King&&view=detail&mid=550A7ABB1DA46C167C80550A7ABB1DA46C167C80&&FORM=VRDGAR

Day 6

What is DNA?

DNA and Genes

DNA is an essential molecule for life. It acts like a recipe holding the instructions telling our bodies how to develop and function. It is located in the nucleus of the cell. 

What does DNA stand for? 

DNA is short for deoxyribonucleic acid. 

What is DNA made of? 

DNA is a long thin molecule made up of something called nucleotides. There are four different types of nitrogen bases: adenine, thymine, cytosine, and guanine. They are usually represented by their first letter:

• A- adenine

• T- thymine

• C - cytosine

• G - guanine

• These nitrogen bases will always pair together- A and T,  C and G 

Holding the nucleotides together is a backbone made of phosphate and deoxyribose which is a type of sugar. 

Different Cells in the Body 

Our bodies have around 210 different types of cells. Each cell does a different job to help our body to function. There are blood cells, bone cells, and cells that make our muscles. 

How do cells know what to do? 

Cells get their instructions on what do to from DNA. DNA acts sort of like a computer program. The cell is the computer or the hardware and the DNA is the program or code. 

The DNA Code 

The DNA code is held by the different letters of the nucleotides. As the cell "reads" the instructions on the DNA the different letters represent instructions. Every three letters makes up a word called a codon. A string of codons may look like this: 

ATC TGA GGA AAT GAC CAG

Even though there are only four different letters, DNA molecules are thousands of letters long. This allows for billions and billions of different combinations. 

Genes

Within each string of DNA are sets of instructions called genes. A gene tells a cell how to make a specific protein. Proteins are used by the cell to perform certain functions, to grow, and to survive. 

Shape of the DNA Molecule 

Although DNA looks like very thin long strings under a microscope, it turns out that DNA has a specific shape. This shape is called a double helix or a twisted ladder.  On the outside of the double helix is the backbone which holds the DNA together. There are two sets of backbones that twist together. Between the backbones are the nucleotides represented by the letters A, T, C, and G. A different nucleotide connects to each backbone and then connects to another nucleotide in the center. 

Only certain sets of nucleotides can fit together. You can think of them like puzzle pieces: A only connects with T and G only connects with C. 

Interesting Facts about DNA

• About 99.9 percent of the DNA of every person on the planet is exactly the same. It's that 0.1 percent that is different that makes us all unique.

• The double helix structure of DNA was discovered by Dr. James Watson and Francis Crick in 1953.

• If you unraveled all the DNA molecules in your body and placed them end to end, it would stretch to the Sun and back several times.

• DNA is organized into structures called chromosomes within the cell.

• DNA was first isolated and identified by Swiss biologist Friedrich Meischer in 1869.

  Activity 1. Watch the Brain Pop : DNA and write 8 things from the video https://www.brainpop.com/health/freemovies/dna/

Activity 2. Complete the handout. Watch the video if you have trouble.

Activity 3. build dna game http://learn.genetics.utah.edu/content/molecules/builddna/

or for a faster paced game......

http://www.nobelprize.org/educational/medicine/dna_double_helix/dnahelix.html

Activity 4. Replicate animal DNA. Go to the file below labeled  DNA activity and follow the directions. 

The DNA in your cells contains genetic information, encoded in the form a linear sequence of nucleotide bases. These sequences of bases contain the instructions for the construction of proteins. Molecules of RNA extract the information from DNA and, along with ribosomes, use that information to construct the proteins specified by the genetic code. This process is called translation.

In the context of genetics, a stop codon is a nucleotide triplet in messenger RNA that signifies the termination of protein translation. Essentially, a stop codon is a specific cluster of nucleotides that tells protein construction mechanisms to stop chaining amino acids into a polypeptide chain. Stop codons are the bits of information that tell the body “Hey! This protein is finished!” Stop codons work by initiating the release of release factors, proteins that disassociate the ribosomal subunits and free the polypeptide chain.

In the human genetic code, there have been identified 3 stop codons, each represented as a triplet of nucleotide bases.

In RNA:

• UAG (“amber”)

• UAA (“opal”)

• UGA (“ochre”)

In DNA:

• TAG

• TAA

• TGA

The three stop codons appear differently in DNA and RNA because RNA contains the U base in place of the T base in DNA.

Stop codons are paired with “start codons” that tell the cellular machinery the beginning of a DNA sequence that specifies a specific protein. Without start or stop codons, the mechanisms that read DNA and RNA would not know where to start and when to finish constructing proteins. The most common start codon is the nucleotide triplet AUG (ATG in DNA). Almost every eukaryotic organism uses the triplet AUG as a start codon.

Mutations  https://www.youtube.com/watch?v=vl6Vlf2thvI l   handout link 

Sometimes mutations occur when DNA is copying itself. These can be harmful, neutral, or beneficial. 

There are three ways that DNA can be altered when a mutation (change in DNA sequence) occurs.

 1. Substitution – one base-pair is replaced by another: Example: G to C or A to T          G C G T C- C C G T T   

2. Insertion – one or more base pairs is added to a sequence: Example: CGATGG –– CGAATGG        GCTACC- GCTTACC 

3. Deletion – one or more base pairs is lost from a sequence: Example: CGATGG –– CATGG    GCTACC -GTACC 

Sometimes these mutations occur from environmental factors. 

for example: radiation, chemicals, drugs, and physical injuries.

harmful mutations: Normal: GGG CTT CTT TTT     Sickle Anemia: GGG CAT CTT TTT

Standards: 7.LS1.8 Construct an explanation demonstrating that the function of mitosis for multi cellular organisms is for growth and repair through the production of genetically identical daughter cells. 

Day 7. 

Activity 1:  complete the graphic organizer 

Graphic organizer

Mitosis

Mitosis is the type of cell division used for growth, repair and asexual reproduction. Mitosis occurs wherever new cells are needed. It produces two cells that are identical to each other, and the parent cell. In mitosis each chromosome is copied exactly. The  new chromosomes are moved to opposite sides of the  cell, before the cell divides leaving one complete set of  46 chromosomes in each of the two new cells.

Growth

Humans are made of millions of cells. This has a number

 of benefits:

• Cells can be specialized to do particular tasks

• Groups of cells can function as organs making a more efficient but complex organism.

• The organism can grow very large

Cell division

New cells are needed throughout life. These are for growth, to replace damaged cells and repair worn out tissues. Normal human body cells  are diploid – they have two sets of each chromosome. When new cells are made, these 46 chromosomes (in other organisms the number is  different) are copied exactly in a process called mitosis.

What is Mitosis?

Mitosis is the process where cells divide to produce new cells. If you cut your hand, new cells are produced to heal the wound. These new cells are produced through this process of mitosis. Your body is continually producing new cells to replace old ones even in the absence of an accident like cutting your hand. New cells are also produced as you are growing. The cell has a very orderly process that is used to produce these new cells which we call mitosis. Almost all organisms (all eukaryotic organisms) produce new cells in this manner. Bacteria on the other hand (prokaryotic organisms) produce new cells through a different, relatively more simple mechanism called binary fission. When discussing mitosis you may also hear about meiosis. The main difference between these two are the number of chromosomes that result in the cells that are produced. Mitosis produces 2 new cells with the full set of 46 chromosomes (diploid) while meiosis produces cells with half the number of chromosomes (23 chromosomes in the haploid set for humans). The cells produced through meiosis are called gametes and are are used for reproduction. Mitosis starts with a diploid cell (46 chromosomes) and ends with 2 diploid cells.

What are the stages of mitosis?

There are 4 main stages of mitosis (prophase, metaphase, anaphase and telophase). 

In prophase the chromosomes condense, the nuclear envelope breaks down, the centrioles move to opposite poles and the spindle fibers attach to the centromeres of each chromosome. The chromosomes are then pulled to the center of the cell (the metaphase plate or equatorial plane). 

Metaphase is defined as the stage when the centromeres of each chromosome are aligned on the equatorial plane.

In anaphase the chromosomes are being pulled to opposite poles. The sister chromatids (copies of each chromosome) separate (disjoin) and then are each pulled to opposite poles (46 to each side).

In telophase the spindle fibers dissociate, and the nuclear envelope reforms around each new set of chromosomes. This is followed by cytokineses where the cell divides into 2 new cells- one around each set of chromosomes within a nucleus.

 Watch it happen at http://www.cellsalive.com/mitosis_js.htm

Activity 1: Watch the video: https://www.youtube.com/watch?v=gwcwSZIfKlM and complete the handout.

another good video: https://www.youtube.com/watch?v=NwwcWqL5hhI&feature=youtu.be 

Activity 2. Make vocab cards for each step. Draw a picture on the front and describe what happens during that stage on the back.

Activity 3.  Complete the top part of your handout ( located at the bottom called label the cell) 

 Go to http://www.biology.arizona.edu/cell_bio/activities/cell_cycle/assignment.html to complete the bottom part

A harder version http://www.rigb.org/education/games/human-body/the-cell-cycle

Activity 4: Practice the stages at Quizlet. 

Activity 5. Put the pictures in the correct order: 

Extra Files

Carbon Cycle WS to the game.docx (12k)Kathy Dougherty, Nov 4, 2018, 2:55 PM

Cell processes study guide.docx (13k)Kathy Dougherty, Nov 3, 2019, 5:44 PM

DIFFUSION Click on the link below to see information on diffusion.docx (13k)Kathy Dougherty, Sep 10, 2017, 12:31 PM

DNA Activity Pages - BrainPOP.pdf (113k)Kathy Dougherty, Sep 23, 2017, 11:36 PM

DNA activity.doc (25k)Kathy Dougherty, Sep 21, 2015, 10:01 PM

Egg Lab.docx (12k)Kathy Dougherty, Sep 10, 2017, 12:50 PM

Label the stages of mitosis.docx (235k)Kathy Dougherty, Sep 19, 2016, 11:12 AM

Reactants and Products.docx (13k)Kathy Dougherty, Sep 19, 2017, 6:26 AM

Taking Notes Day 3 and 4.doc (25k)Kathy Dougherty, Sep 13, 2015, 8:56 PM

The Carbon Cycle.docx (32k)Kathy Dougherty, Sep 10, 2016, 6:10 AM

cell process Virtual Lab.docx (12k)Kathy Dougherty, Sep 5, 2016, 9:11 AM

cell processes day 1.docx (101k)

cell processes picture guide.docx (321k)Kathy Dougherty, Sep 7, 2016, 5:00 PM

diffusion lab.pdf (156k)Kathy Dougherty, Oct 28, 2018, 2:40 PM

dnacoloring.pdf (79k)Kathy Dougherty, Sep 23, 2017, 11:37 PM

leaf cross section.docx (114k)Kathy Dougherty, Sep 17, 2017, 7:26 PM

mitosis and meiosis compare and contrast.docx (71k)Kathy Dougherty, Jan 2, 2020, 12:34 PM

the cell and its environment 2010.ppt (1501k)Kathy Dougherty, Sep 7, 2015, 7:29 AM