Cell Review

All cells include the following parts: A cell is the smallest part of any living thing.  There are many parts of a cell.   Each part of a cell, called an organelle completes a certain function for the cell. All cells include the following parts: Cell Membrane - forms the outer boundary of the cell and allows only certain materials to move into or out of the cell Cytoplasm - a gel-like material inside the cell;  it contains water and nutrients for the cell Nucleus - directs the activity of a cell; it contains chromosomes with the DNA Nuclear Membrane - separates the nucleus from the cytoplasm Endoplasmic Reticulum - moves materials around in the cell Ribosomes - make protein for the cell Golgi Bodies - are used for packaging and secreting of energy Mitochondria - break down food and release energy to the cell Lysosomes - are chemicals used to digest waste Vacuoles - are storage areas for the cell

Animal Cell Plant Cell Some organelles are found only in Plant cells. These organelles are: Cell Wall - provides structure to the plant cell Chloroplasts - contain chlorophyll which makes food for the plant cell

There are many types of cells There are many types of cells. Cells are unique to each type of organism. Humans have hundreds of types of cells. Some cells are used to carry oxygen (O2) through the blood (red blood cells) and others might be specific to the heart. If you look at very simple organisms, you will discover cells that have no defined nucleus- prokaryotes -and other cells that have hundreds of nuclei (multinucleated). The thing they all have in common is that they are compartments surrounded by some type of Membrane SOME QUESTIONS: How many cells are in your body? 1,000,000,000,000,000 What is the primary function of a cell? To survive!

READ ONLY: In the same way that cells survive in different ways; all cells have different types and amounts of organelles. The larger a cell becomes the more organelles it will need. It makes sense if you think about it. If you are a big cell, you will need to eat more than a little cell. You will also need to convert that food into energy. A larger cell would need to eat more and may wind up having more mitochondria to process that food into energy. While they might have a purpose, more advanced cells have a difficult time surviving on their own. A cell from your brain could not survive in a Petri dish for long. It doesn't have the right pieces to live on its own. It does have the ability to transmit electrical systems around your body. An amoeba could survive in a dish forever, thrive, and reproduce. On the other hand, that amoeba will never help you transmit electrical impulses. The brain cell is far more advanced and has specific abilities and organelles. Simpler cells have a better chance of surviving on their own while complex cells can accomplish tasks that are more advanced.

Focus Prokaryotes Eukaryotes There are two major types of cells: - Include single celled organisms like bacteria -No proper “nucleus” -Use a rudder like “flagellum” to get around -Asexual reproduction (offspring have the exact characteristics of parent cell) -Because of this, very little evolution has taken place -Account for the majority of organisms on our planet -Can live in almost every imaginable environment -A large DNA molecule resides in the center -Come in spiral, spherical, rod, and comma shapes -Include the fungi, plant, and animal kingdoms -Much larger than prokaryotes -More complex, with various independent organelle and protein functions -Contain much more genetic information (DNA) in a distinct nucleus -Reproduce sexually, allowing more transferred variation over time (evolution) -Oldest fossils date to 1.5 billion years ago – 2 billion years later than prokaryotes

In singled celled organisms, like bacteria, cell division explains how new organisms are produced (procreation). Likewise, the cells within multi-celled organisms also divide in order to allow tissue growth. This is also way to replace worn out cells. This can only occur so many times in a body however. Apart from cancer cells, cells in tissue eventually stop dividing as the body grows older. This is called aging!

There are 3 main ways cells reproduce: Binary Fission- Occurs only in prokaryotes (bacteria, amoebas) when the cell divides into to equal parts – each capable of growing to the size of the original cell. DNA only has one origin. Mitosis- A series of phases where a eukaryote (cells in plants, fungi, and animals) divides into two cells identical to each other and the parent cell. This is unique because a copy of complete chromosomes is transferred to each. Meiosis- (Very complex) Essential for sexual reproduction and therefore occurs in all eukaryotes. A mother and father set of DNA from the original cell’s nucleus gets copied to eventually 4 new cells, which are thus different than the parent cell.

TASK: “Create your own diagram comparing and constrasting animal and plant cells” Grading / Requirements: ___________________________________________________ 5pts. Show and label Organelles or parts (use color in your design) 5pts. Accurately depict the characteristics and location of included parts 5pts. Provide a short description of the function or significance of each part as well as any additional information covered in class 5pts. Include Photosynthesis and Respiration concepts covered in notes 5pts. End product should be neat and organized 5pts. Work should reflect appropriate use of class time Total available points: 30