Bio Chapter 7 - Cell Functions

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Lesson 7.1 - Intro To Cellular Life

Study - New Technology allowed people to study the ==movement== and ==structure== of cells

Microscopes:

• Electron microscopes reveal details @@1000 times bigger@@ than visible in light microscopes
• Transmission electron microscopes are used to show cell structure and large protein molecules. Electrons go through and need to be %%cut into slices%%
• Scanning ^^electron^^ microscopes ^^create 3D images^^. Electrons bounce off of and ^^do not have to be cut^^ into small slices

Prokaryotes + Eukaryotes:

• Types of ==Cells== Include:
  • Bacteria, @@plants@@, animals, fungi, protists
• All Cells Include:
  • Cell Membrane
  • %%Cytoplasm%%
  • ^^Ribosomes^^
  • ==DNA==
• @@Prokaryotes@@:
  • Genetic material not contained
  • No %%membrane-bound organelles%%
  • ^^Smaller^^ than eukaryotic cells
  • ==Bacteria==
• @@Eukaryotes@@:
  • DNA is stored in the nucleus
  • %%Long%% and %%complex%%
  • Contain ^^dozens of structures and internal membranes^^
  • Highly ==specialized==
  • @@Plants, animals, fungi, protists@@
• Discovery of Cells
  • %%James Hooke%% coined the term “cell”
  • He was attempting to study ^^cork^^
  • Antonie Van Leeuwenhoek observed microorganisms in ==pond water under a microscope==
  • Matthias Scheider concluded that all plant tissue is made of cells and that cells are a @@basic unit of life@@
  • Theodore Schwann concluded that all animal tissue is made of cells
• %%Properties%% of Cells/Cell Theory
  • All organisms consist of ^^1 or more cells^^
  • Cells are the ==basic unit of life== and ==structure== of all organisms
  • All cells come from @@preexisting@@ cells

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Lesson 7.2 - Eukaryotic Cell Structure

• Eukaryotic Cell Structures:

  • Organelles: %%Preform cell functions%%
  • 2 Parts: ^^Nucleus + Cytoplasm^^
  • Cytoplasm is ==outside the nucleus==

• @@Plant@@ Cell:

  

• Animal Cell:

  

• %%Endomembrane%% System:

  • Nucleus - ^^Holds instructions^^
  • Ribosomes - ==Build==
  • ER - @@Shape@@
  • Golgi - Modify/Sort/Package
  • Vesicles - %%Ships%%

• ^^Nucleus^^:

  • ==Control== center
  • Holds @@instructions for making proteins@@
  • Surrounded by 2 nuclear envelopes
  • Envelopes contain %%pores that only RNA can pass through%%
  • Granular material in the nucleus - ^^Chromatin^^
  • Chromatin - ==made of RNA and protein==
  • When a cell divides, @@chromatin condenses to become chromosomes@@. These contain @@genetic info@@
  • The nucleolus only holds info to make more ribosomes

• %%Ribosomes%%:

  • Small particles of ^^RNA and protein^^ found ^^freely throughout the cytoplasm^^
  • Create proteins in “==Protein Synthesis==”
  • Follow @@instructions from the nucleus and RNA@@

• ER:

  • %%Rough%% ER (%%Part of protein synthesis%%) + %%Smooth%% ER (%%Not%% part of protein synthesis)
  • ^^Ribsomones^^ on Rough ER are ^^found on the surface^^
  • ==Rough== ER - ==Proteins are assembled== on ribosomes
  • @@Smooth@@ ER- Creates @@lipids@@ and @@detoxifies@@ drugs

• Golgi Apparatus:

  • Proteins are %%moved from ER to Golgi%%
  • ^^Modifies, Sorts, and Packages^^ proteins
  • Sends to ==vesicles== which send to their ==necessary location==

• Making @@Proteins@@:

1. Nucleus
2. Nuclear %%Pore%%
3. ^^Ribosome^^
4. ==Protein==
5. @@Rough@@ ER
6. Golgi Body
7. %%Vesicle%%
8. Cell ^^Membrane^^ + to a ^^new location^^

• ==Lysosomes==:
  • Small @@organelles filled with enzymes@@
  • Break down lipids, carbs, and proteins into things that can be used by the rest of the cell
  • %%Breaks down organelles%% that %%no longer have a use%%
  • ^^“Trash/Recycle”^^
• ==Vacuoles==:
  • @@Saclike@@ structures
  • Store water, salts, proteins, and carbs
  • Holds %%pigments + toxins as defense mechanisms%%
  • In ^^plant^^ cells - the ^^central vacuole is filled with liquid^^ that is used for ^^photosynthesis^^ + helps the ^^plant stand upright^^
  • ==Unicellular== Organisms - ==filled with water== and have a ==pump to help from exploding==
• @@Mitochondria@@:
  • Convert energy from food into compounds that can be used more conveniently by the rest of the cell
  • Enclosed by %%2 membranes%%
  • More ^^folds^^ = more ^^surface area^^ = more ^^energy^^ = more ^^ATP^^
• ==Choloplasts==:
  • Capture @@energy from the sun@@ and @@convert it into chemical energy@@
  • Photosynthesis
  • Surronded by %%2 membranes%%
  • Contain ^^chlorophyll^^
• ==Cytoskeleton==:
  • Gives @@eukaryotic cells their shape@@
  • A network of protein filaments
  • Also involved in %%cell movement%%
• ^^Microfilaments^^:
  • ==Thread-like== structures made of the ==protein actin==
  • Make @@extensive networks in cells@@
  • Make a tough, flexible framework that supports the cell
  • Helps %%move cells%%
• ^^Microtubules^^:
  • ==Hollow structures== that are made up of the ==protein tubulins==
  • Help @@maintain cell shape@@
  • Helps cells divide (mitosis+meosis)
  • Build %%projections from the cell surface%% that enable %%cells to swim rapidly through liquids%%
  • ^^Centrioles^^ are also formed from ^^tubulins^^
  • These are ==located near the nucleus== and help ==organize cell division==

Lesson 7.3 - Cell Boundaries

• All cells have a @@thin, flexible barrier@@ known as the @@cell membrane@@

• Plants, fungi, bacteria + some protist cells also produce a stronger layer known as a cell wall

  • The %%main function%% of the cell wall is to %%provide support and protection%% for the cell
  • ^^No movement^^ - extra ^^padding^^
  • Also ==attacks bacteria==
  • Lies @@outside the cell membrane@@
  • Porous enough to allow water, oxygen, carbon dioxide, and other substances to easily pass through

• Cell %%Membrane%%

  • Regulates what ^^enters and exits the cell^^
  • Provides ==support and protection== for the cell

  

• The composition of @@nearly all cell membranes@@ is made of a @@double-layered sheet@@ called a @@lipid bilayer@@

  • Gives a flexible structure that forms a barrier between a cell and its surroundings
  • Contains %%protein molecules%% embedded in the %%lipid bilayer,%% some of which have %%carb molecules attached to them%%

• ^^Diffusion^^ Through Cell Boundaries

  • Every ==cell== lives in a ==liquid environment==
  • The @@cell membrane regulates@@ the @@movement of diffusion@@ from the liquid on @@one side of the membrane to another@@
  • Particles tend to move from areas of high concentration to low concentration
  • This is the %%process of diffusion%%
  • This will continue until a ^^state of equilibrium is reached^^

  

• ==Passive== Transport

  • Depends upon @@random particle movements@@
  • Substances diffuse across membranes without using energy
  • This is called %%passive transport%%

• ^^Osmosis^^

  • Diffusion of ==water== through a ==selectively permeable membrane==
  • Water - @@solvent@@ - what is @@doing the dissolving@@

  

• Levels of Concentration

  • %%Water%% diffuses from %%areas of high to low concentration%%
  • ^^More concentrated^^ solution - ^^Hypertonic^^
  • Area of ==high concentration==
  • Water with @@more sugar present@@
  • Less concentrated solution - Hypotonic
  • Area of %%low concentration%%
  • Water with ^^less sugar present^^
  • Water with ==equal parts sugar and water==
  • @@Isotonic@@
  • Osmosis is only concerned with water and its’ levels
  • Particles %%never stop moving,%% as they must always %%work to maintain homeostasis%%

• Osmotic ^^Pressure^^

  • Occurs when ==water on the hypertonic side puts pressure on the membrane==
  • The @@cell@@ is almost always @@hypertonic to fresh water@@
  • If a cell has too much water, it is at risk of exploding or bursting (which leads to the death of the cell)
  • Cells in %%large organisms%% and with %%cell walls%% are much %%less likely to burst%%

• ^^Facilitated^^ Diffusion

  • Membranes contain ==integral proteins== that can ==assist in the movement of larger particles==
  • The @@use of these proteins@@ is called f@@acilitated diffusion@@
  • Protein channels are specific to certain particles only
  • Ex. %%Glucose Transport%% - Only for %%glucose%%
  • ^^Fast^^ and ^^Specific^^
  • Still ==considered diffusion==
  • Only occurs from @@high to low concentration@@

• Active Diffusion

  • Occurs when materials have to %%move from areas of low to high concentration%%
  • ^^Against^^ the ^^concentration difference^^
  • Requires ==energy==
  • Ex. @@Stuffing things into a closet@@

• Molecular Transport

  • Small molecules are %%carried by proteins%%
  • Allows movement from ^^low to high^^
  • Requires ==energy==

• @@Large Particle@@ Transport

  • Occurs when particles are too large to be carried by proteins
  • %%Active%% transport

• ^^Endocytosis^^

  • Process of ==taking material into the cell by means of pockets of the cell membrane==
  • A @@vacuole@@ is formed around the material that @@works to bring it into the cell@@
  • This vacuole is from the cell membrane

• %%Phagocytosis%%

  • The ^^process of cytoplasm surrounding food^^
  • This is then ==engulfed by the cell==
  • Requires @@energy@@
  • Collect
  • Pinch Off
  • Turns to Vesicle
  • Engulfed by Cell

• %%Pinocytosis%%

  • The process of ^^cytoplasm surrounding waste^^
  • This is then ==removed from the cell==
  • Requires @@energy@@
  • Collect
  • Pinch Off
  • Turns to Vesicle
  • Released

• %%Exocytosis%%

  • The ^^release of waste from a cell^^
  • Cell membrane ==fuses with waste from inside the cell==
  • Then @@removes it from the cell@@
  • Requires energy

Lesson 7.4 - Diversity of Cellular Life

• %%Unicellular%% Organisms
  • Made of ^^only 1 cell^^
  • ==Dominate life on Earth== because so ==many of them can fit== per any given space ==compared to multi==
  • Includes: @@All bacteria@@ cells, @@certain eukaryotic organisms@@ (yeast + amebas)
• Multicellular Organisms
  • Made of %%many cells%%
  • ^^Great variety^^ in these cells
  • Includes: ==All plant cells, all animal cells, most fungus cells, some protist cells==
• @@Specialized Animal@@ Cells
  • Red blood cells transport oxygen
  • Cells in the %%pancreas produce a protein%% (endomembrane systems)
  • ^^Muscle^^ cells ^^allow for movement^^
• ==Specialized Plant== Cells
  • Exchange @@carbon dioxide, oxygen, water vapor,@@ and other gases through @@stomata@@
  • Guard cells surround the stomata and regulate the exchanges
• %%Levels%% of Organization
  • ^^Individual^^ Cells - 1st level of organization
  • ==Tissues== - ==Cells are grouped== and create these
  • A @@group of similar cells that perform a particular function@@
  • Organ
  • Organ Systems
  • Organism
  • Ex. %%Muscle cell > Smooth muscle tissue > Stomach > Digestive System%%
• Types of ^^Tissue (Animals)^^
  • ==Muscle - Moves==
  • @@Skin - Epithelial@@
  • Nervous - Neurons
  • %%Connective - Ligaments/Cartlidge%%
• ^^Organs (Animals)^^
  • Groups of ==tissues that work together to perform a specific function==
  • Completes a @@series of specialized tasks@@
  • Work together to create organ systems
  • %%Nervous System%%
  • %%Circulatory System%%
  • %%Skeletal System%%
  • %%Digestive System%%

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