From 8c0195e3cbd549a2f9ebd89cb34bd8f2bc4cb94d Mon Sep 17 00:00:00 2001 From: Daniel Chen Date: Mon, 28 Oct 2019 01:20:33 +0000 Subject: [PATCH 1/2] Update Unit 2: Biology.md --- Grade 10/Science/SNC2DZ/Unit 2: Biology.md | 149 +++++++-------------- 1 file changed, 47 insertions(+), 102 deletions(-) diff --git a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md index ad5ecee..65a2b18 100644 --- a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md +++ b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md @@ -40,150 +40,95 @@ A person contains roughly 100 trillion cells ### Cell Membrane -- Controls what substances enter/leave the cell selectively via various receptors/osmosis + - Controls what substances enter/leave the cell selectively via various receptors/osmosis - Allows nutrients to enter - Allows waste products to leave -- Surrounds and holds other organelles in cell -- Interact with outside chemicals (e.g., hormones) + - Surrounds and holds other organelles in cell + - Interact with outside chemicals (e.g., hormones) ### Nucleus -- Holds deoxyribonucleic acid (DNA) in form of `chromatin` + - Holds deoxyribonucleic acid (DNA) in form of chromatin - DNA is a double helix that make genes - - `Genes` are a complete set of instructions to make a complete product (typically proteins) + - Genes are a complete set of instructions to make a complete product (typically proteins) - `Genes`: one of the many sets of instructions, in your DNA, found on a **chromosome**, for making a functional product (mostly proteins) - - `Chromatin` is DNA wrapped tightly in protein -- `Chromosomes` are even more tightly wrapped chromatin used in cell division only -- Surrounded by a double membrane -- Substances enter and exit the nucleus via nuclear pores -- Messenger RNA (mRNA) is encoded from DNA and sent to `ribosomes` to produce proteins + - Chromatin is DNA wrapped tightly in protein + - Chromosomes are even more tightly wrapped chromatin used in cell division only + - Surrounded by a double membrane + - Substances enter and exit the nucleus via nuclear pores + - Messenger RNA (mRNA) is encoded from DNA and sent to ribosomes to produce proteins ### Nucleolus - Dense region of DNA located in the nucleus - This area of DNA is specially for ribosomal DNA (rDNA), or DNA used to make ribosomes - - Produce "large" and "small" subunits of ribosomes, which either form complete ribosomes in cytosol or mix with endoplasmic reticulum, forming rough endoplasmic reticulum (RER) - - Is *not* surrounded by a membrane, literally is just same as rest of nucleus but denser + ### Cytoplasm & Cytosol - - `Cytosol` is the fluid cells contain - - **All organelles** are suspended in `cytosol` - - `Cytoplasm` is the `cytosol` along with everything in a cell, excluding the nucleus + - Cytosol is the fluid cells contain + - All organelles are suspended in cytosol + - Cytoplasm is the cytosol along with everything in a cell, excluding the nucleus ## Endoplasmic Reticulum -- The endoplasmic reticulum is a network of tubules and flattened sacs with a "rough" appearance because of the presence of `ribosomes` on the surface - Network of tubules and flattened sacs -- **Transport** proteins via cytoskeleton in vesicles +- Transport proteins via cytoskeleton in vesicles -## Rouch Endoplasmic Reticulum -- Appears "rough" due to the `ribosomes` attached to its outer surface +### Specific to Rough ER +- Appears "rough" due to the ribosomes attached to its outer surface - Located directly adjacent and attached to nucleus -- Located next to `Golgi apparatus` -- `Ribosomes` in rough ER synthesize proteins - - Only specific proteins are synthesized by ribosomes of rough ER - - Proteins synthesized in `ribosomes` of rough ER are always sent to either `Golgi apparatus` via `vesicles` or stay in `rough ER` - - `Ribosomes` attach to and leave the `rough ER` regularly +- Located next to Golgi apparatus +- Ribosomes in rough ER synthesize proteins - About half the cell's proteins are produced here -- **Modify, fold, and fix proteins** +- Modifies, folds, and fixes proteins -### Functions -- **Protein synthesis** - - About half of the cell's proteins are made here, by the `ribosomes` -- **Protein movement** - - Proteins are transported by vesicles throught the cell to other organelles, like the `golgi apparatus` -- **Protein "Proof-Reading"** - - pre-existing proteins can enter the `rough-ER` for **modification** - -## Smooth ER +### Specific to Smooth ER - Does not synthesize proteins -- Appears "smooth" due to lack of `ribosomes` +- Appears "smooth" due to lack of ribosomes - Located directly adjacent and attached to nucleus - Synthesizes lipids (fats, e.g., cholesterol) - Metabolises carbohydrates -## Golgi Apparatus (Golgi Complex) -- **Receives, modifies and transports** proteins that were produced by the `rough-E.R` -- **Packages** proteins into `vesicles` and sends them `cell membrane` for export - ## Lysosome -- `White blood` cell uses the cytoskeleton to reach out and swallow up a bacterium, then uses `lysosomes` to break it down -- Spherical vesicle that contains `enzymes` -- Digests and kills foreign matter which is then excreted -- Digests and breaks down old and unused material to be recycled -- Digests and breaks down old or non-functional organelles as needed -- Only plays a very minor role in cell suicide (`apoptosis`) -- If lysosome does rupture (accidentally) everything dies + - Spherical vesicle that contains enzymes + - Digests and kills foreign matter which is then excreted + - Digests and breaks down old and unused material to be recycled + - Digests and breaks down old or non-functional organelles as needed + - If lysosome does rupture everything dies, hence they are called `suicide sacs` -### Functions -- **Digestion** - - Food or foriegn matter (invaders) are swallowed up and executed -- **Recycling** - - When an organelle "dies" `lysosomes` will recycle the dea material back into raw materials cellular suicide -- **Cellular suicicde** - - This is not good for the cell (obviously, but it is good for us. (E.g reasons why most of us don't have web feet/hands) - -## Midtochondria +## Mitochondrion - **Plural is "mitochondria"** - Contains an inner and outer membrane - Processes glucose + oxygen gas to form carbon dioxide + adenosine triphosphate (ATP) - ATP allows proteins to do things (e.g., spend 1 ATP break 1 molecule) - ATP cannot be stored - - Mitochondria have their own DNA ## Cytoskeleton -- The cytosekleton **is** the skeleton of the cell, found in the `cytosol`, made up of protein. -- The cytoskeleton is also like the muscular system, able to change teh sahpe of cells in a flash -- Made of protein filaments -- Maintains and changes cell structure, much like a human skeleton + muscular system + - Made of protein filaments + - Maintains and changes cell structure, much like a human skeleton + muscular system - Moves cells -- Chemicals can travel along cytoskeleton, e.g., organelles, vesicles, etc. + - Things can travel along cytoskeleton, e.g., organelles, vesicles, etc. -## Organelles Specific To Animal Cells -1. centrioles and centrosomes -2. lysosomes - -### Centrioles and Centrosomes -- Involved in the process of cell division for animal cells, plant cells **DO NOT** use centrioles +## Organelles specific to animal cells +### Centrioles and centrosomes - Made of same protein as cytoskeleton - A centrosome is a pair of centrioles - - Very important to cell division - - Split chromosomes apart after DNA has been replicated into daughter cells - - Helps regulate cell division + - Important to cell division - Create cilia and flagella (e.g., small hair-like things that swipe dirt out of lungs and tails of sperm, respectively) ### Lysosomes -- Present in all animal cells but not present in the cells of most plants - -## Organelles Specific To Plant Cells -1. Cell wall -2. Chloroplast -3. Central Vacuole +## Organelles specific to plant cells ### Cell wall -- Provides structure and prevents cell rupture -- Can be tough, flexible, and/or rigid -- Permeable to small molecules -- Made of cellulose (type of sugar) -- Also present in most bacteria, fungi, and protists - -### Chloroplast -- The `solar panel` of the plant cell. -- Conducts photosynthesis -- All chlorophyll is located in chloroplasts -- Looks green - -### Central Vacuole -- Extremely large, may take up to 90% of volume in cell -- Contains water -- Maintains `turgor` pressure against cell wall (pushes against cell wall in all directions) -- **Provides the cell with shape** - - - - - - - - - + - Provides structure and prevents cell rupture + - Can be tough, flexible, and/or rigid + - Made of cellulose (type of sugar) + - Also present in most bacteria, fungi, and protists +### Central vacuole + - Extremely large, may take up to 90% of volume in cell + - Contains water + - Maintains turgor pressure against cell wall (pushes against cell wall in all directions) +### Chloroplasts + - Conduct photosynthesis + - All chlorophyll is located in chloroplasts + - Looks green \ No newline at end of file From 6fa22b937fc0eabcd207284bfb7948d7aa2e66fa Mon Sep 17 00:00:00 2001 From: Daniel Chen Date: Mon, 28 Oct 2019 01:22:34 +0000 Subject: [PATCH 2/2] Update Unit 2: Biology.md --- Grade 10/Science/SNC2DZ/Unit 2: Biology.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md index 65a2b18..4803b62 100644 --- a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md +++ b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md @@ -76,7 +76,7 @@ A person contains roughly 100 trillion cells - Appears "rough" due to the ribosomes attached to its outer surface - Located directly adjacent and attached to nucleus - Located next to Golgi apparatus -- Ribosomes in rough ER synthesize proteins +- Ribosomes in rough ER synthesize proteins which are sent to Golgi apparatus for packaging and distribution - About half the cell's proteins are produced here - Modifies, folds, and fixes proteins