From f4885746454163e7e6237270f9cbdd36e08dbe2e Mon Sep 17 00:00:00 2001 From: Daniel Chen Date: Fri, 25 Oct 2019 14:08:27 +0000 Subject: [PATCH] Update Unit 2: Biology.md --- Grade 10/Science/SNC2DZ/Unit 2: Biology.md | 58 +++++++++++++++------- 1 file changed, 40 insertions(+), 18 deletions(-) diff --git a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md index 970602e..7adfab8 100644 --- a/Grade 10/Science/SNC2DZ/Unit 2: Biology.md +++ b/Grade 10/Science/SNC2DZ/Unit 2: Biology.md @@ -1,27 +1,49 @@ -# Unit 2 Biology -- Tissues -- Organs, -- Systems of living things +# Unit 2: Biology -## Celular Biology -A person contains roughly 100 billion cells -- there are roughly to different types of cell s found in mammals -- cells are roughly 20 $`\um`$ (micrometer, $`10^{-6}`$ m), around 250 cells / cm +## Cellular Biology +A person contains roughly 100 trillion cells +- Cells are roughly 20 `μm` (micrometre, 10-6 m), around 250 cells / cm ## Cell Theory 1. All living things are composed of cells -2. cells are the basic units of living organisms -3. all cells came from pre-existing cells +2. Cells are the basic units of living organisms +3. All cells came from pre-existing cells -## Types Of Cells -`Prokaryotic cell`: Meaning before/lacking +## Eukaryotic versus Prokaryotic Cells +`Prokaryotic cell`: Meaning before/lacking nucleus -`Eukaryotic cell`: Has organelles, meaning true, complete. +`Eukaryotic cell`: Means complete nucleus -|Part Of Cell|Prokaryotic|Eukaryotic| +|Factors|Prokaryotic|Eukaryotic| |:-----------|:----------|:---------| -|DNA|In nucleoid region|Usually in membrane, bound nucleus| +|DNA|In nucleoid region|Usually in membrane-bound nucleus| |Size|Usually smaller|Usually larger| -|Organelles|No membrane, bound organelles|Membrane, bound organelle, the bigger, the more complex| -|Organization|Usually singler celled|Often multicellular| -|Metabolism|May not need oxygen|Usually needs oxygen to exist| \ No newline at end of file +|Organelles|Not membrane-bound, smaller|Membrane-bound, more complex| +|Organization|Usually singlecelled|Often form multicellular organisms| +|Metabolism|May not need oxygen|Usually need oxygen| + +## Cellular Organelles + +### Cell Membrane + - 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) + +### Nucleus + - 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) + - 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) + - Produce "large" and "small" units of complete ribosomes, which either remain free 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 +