Merge branch 'patch-4' into 'master'

WIP:Give more detail on ERs, add information on lysosomes, mitochondria,...

See merge request magicalsoup/Highschool!14

Grade 10/Science/SNC2DZ/Unit 2: Biology.md

@@ -70,15 +70,75 @@ A person contains roughly 100 trillion cells
  - All organelles are suspended in cytosol
  - Cytoplasm is the cytosol along with everything in a cell, excluding the nucleus
 
-## Rough 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
+## Endoplasmic Reticulum
+- Network of tubules and flattened sacs
+- Transport proteins via cytoskeleton in vesicles
 
-### Function
-- 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 are center the rough-ER for modification
+### 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
+    - About half the cell's proteins are produced here
+- Modify, fold, and fix proteins
 
+### Smooth ER
+- Does not synthesize proteins
+- Appears "smooth" due to lack of ribosomes
+- Located directly adjacent and attached to nucleus
+- Synthesizes lipids (fats, e.g., cholesterol)
+- Metabolises carbohydrates
 
+## Lysosome
+ - 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
+
+## 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
+ - 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.
+
+## 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
+ - Create cilia and flagella (e.g., small hair-like things that swipe dirt out of lungs and tails of sperm, respectively)
+
+### Lysosomes
+
+## 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
+
+### 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