From 68d5b242dc3fe873d2f03b8b43d0df7428b0b372 Mon Sep 17 00:00:00 2001 From: Daniel Chen Date: Mon, 2 Dec 2019 03:20:38 +0000 Subject: [PATCH] Put everything in, fix later merge plz --- Grade 10/Science/SNC2DZ/Unit 2: Biology.md | 111 +++++++++++++++++---- 1 file changed, 89 insertions(+), 22 deletions(-) diff --git a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md index f1f9052..64f772a 100644 --- a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md +++ b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md @@ -1,6 +1,5 @@ # Unit 2: Biology -## Cellular Biology A person contains roughly 100 trillion cells - Cells are roughly 20 `μm` (micrometre, 10-6 m), around 250 cells / cm @@ -22,22 +21,7 @@ A person contains roughly 100 trillion cells |Organization|Usually singlecelled|Often form multicellular organisms| |Metabolism|May not need oxygen|Usually need oxygen| -## Cellular Organelles - -### Business Analogy - -| In a business | In a cell | -| ------------- | --------- | -| Building | Cytoplasm & Cytoskeleton | -| Department Head | Organelles | -| Boss | DNA | -| Workers | Ribosomes & Enzymes | -| Waste management | Lysosomes | -| Storage | Vacuoles | -| Powerhouse | Chloroplasts & Mitochondria | -| Security gate | Cell membrane controls entrance and exit from the cell | -| Transportation Department | IMPORT: Cell membranes and vesicles, INTERNAL: Endoplasmic reticulum & vesicles, EXPORT: Golgi apparatus, vesicles, and cell membrane | - +## Organelles ### Cell Membrane - Controls what substances **enter/leave** the cell selectively via various receptors/osmosis @@ -226,11 +210,11 @@ A person contains roughly 100 trillion cells - `Zygote`: A single-celled organism formed from the fertilization of an egg by a sperm cell, is a totipotent stem cell - A cell's position in the `gastrula` (outer, middle, inner layer) will determine the fate of the cell, or its potiental. - Chemical signals from other cells will also determine activated genes that lead to specialisation -- (LOCATION LOCATION LOCAION!) +- (LOCATION LOCATION LOCATION!) - Specialisation is determined by reading only certain genes ### Stem Cells -- They are an **unspecialized** cell that has the potential to become one of several types of cells. +- **Unspecialized** cells with the potential to become one of several types of cells. - Can either divide to two stem cells or one stem cell and one specialised cell - Specialised cells generally do not divide @@ -355,7 +339,6 @@ A person contains roughly 100 trillion cells - Intestines - Pancreas makes most digestive enzymes and pumps them in the duodenum - Absorbs nutrients and water to bloodstream - - Duodenum digests food chemically even more - Forms and excretes feces - Contains smooth muscle to continue peristalsis - Contains plenty of blood vessels for faster nutrient absorption @@ -368,7 +351,7 @@ A person contains roughly 100 trillion cells ## Respiratory system - Exchanges oxygen gas and carbon dioxide gas between red blood cells and the surrounding air, which is required for cellular respiration - Diaphragm contracts to lower itself, causing the rib cage to rise, which increases lung volume, which subsequently causes pressure to decrease and air to rush in to the lungs - - Diaphragm relaxes to return everything to its normal position + - Diaphragm relaxes to return everything to its normal position - Air is warmed and moisted while passing through nasal cavity blood vessels - Trachea and bronchi are made of rigid cartilage rings - Prevents airways from closing, similar to a vacuum hose @@ -467,4 +450,88 @@ A person contains roughly 100 trillion cells - Chance of disease from the vaccine are far lower than chance of death or serious infection from a pathogen - Vaccines do not cause autism or seizures, but may act as a trigger for the latter due to genetics -## Musculoskeletal system \ No newline at end of file +## Musculoskeletal system + - Maintains **structure** + - **Protects** other systems and cells + - Enables **movement** + - Four types of **connective tissues**: Ligaments, tendons, bones, and cartilage + +| **Bone** | **Information** | **Location** | +| :--- | :--- | :--- | +| Clavicle | Collarbone | Collar | +| Humerus | Funny bone | Lower upper arm | +| Femur | Largest bone | Thigh | +| Tibia | One of two bones in lower leg | Front lower leg | +| Vertebrae | Enable spinal movement | Spine | +| Patella | Prevents leg overextension and protects knee join | Kneecap | + +### Bones + - Hard and dense + - Bone cells produce minerals (e.g., phosphorus + calcuium) and **collagen** + - Minerals for strength, collagen for flexibility + - Bone marrow produces blood cells + - Contain blood cells + +### Joints + - Anywhere where two bones meet + - Types of joints + - Hinge joint (e.g., knee, elbow) + - Ball and socket joint (e.g., Hip, shoulder) + - Fixed (e.g., skull, pelvis) + - `Ligaments` connect bones across joints + - `Cartilage` cushions bone on each side of joint and allows for smooth motion + +### Skeletal Muscle + - Made of **striated** muscle fibres of long cells + - Voluntary muscles, receive signals from brain via nerves + - Always come in pairs as **any muscle can only pull, not push** + - Must be attached to two bones in order to move a bone + +## Nervous System + - Coordinates body activities + - `Central nervous system`: Brain + spinal cord + - `Peripheral nervous system`: All other nerves connecting everything to spinal cord/brain + - `Neurons` send electric signals down their singular long `axon` branch thing + - They accept signals from `dendrites` on the main cell body + - `Schwann cells` form the `myelin sheath` to insulate and nurture the axon, protecting it from interference + - Neurotransmitters are chemical signals that transmit information between neurons + - Electrical signals tell chemical signals to go to other neurons + - Nerves + - Bundle of axons + - Surrounded with blood vessels and connective tissue + - Nerve signals are short-lived, fast, and targeted towards specific groups of cells + +### Disorders + - Parkinson's disease + - Loss of brain neurons that send neurotransmitters to muscles + - Leads to muscular and mental decline + - Multiple sclerosis + - Immune system attacks myelin sheath + - Disruption of neurons' electric signals due to lack of protection + - Causes spasms and loss of muscular control + - Alzheimer's disease + - Protein deposits (plaque) build up in brain tissue + - Leads to memory loss and total system failure + +## Endocrine System + - Coordinates organ functions + - `Hormone` chemical signals produced by endocrine glands that, compared to nerve signals, are **long-lasting**, **slower**, and **general** + - Specific hormones bind to specific receptors on specific cell membranes (e.g., mailing lists) + - Hormones travel through the bloodstream + - Hormones either encourage or discourage activity + - Can cause positive or negative feedback loops with glands + +| **Endocrine organ** | **Purpose** | **Location** | +| :--- | :--- | :--- | +| Pituitary gland | Controls growth and development | Brain | +| Pancreas | Secretes insulin to ensure sugar in bloodstream is taken in by cells | Attached to duodenum | +| Gonads (ovaries + testes) | Secretes the reproductive hormones testosterone and estrogen, respectively | Lower abdomen | +| Adrenal glands | Control stress response, secrete adrenaline (fight/flight response) | Above kidneys | + +### Disorders + - Type 1 diabetes: The pancreas is unable to produce any insulin, resulting in high blood sugar + - Generally caused by genetics + - Type 2 diabetes: The pancreas produces not enough insulin and/or cells are resistant to it, resulting in high blood sugar + - Generally caused by lifestyle choices (e.g., diet) + - Growth disorders (dwarfism/gigantism) + - Caused by poor pituitary and/or hypothalamus function or endocrine gland damage as an adult \ No newline at end of file