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Cells Biology 12 Cheat Sheet (DRAFT) by

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Intere­sting facts

Longest cells in humans are motor neurons 1.37 meters
Every square inch in human average 32 billion bacteria
Human shed 600,000 particles of skin every hour
Humans regrow outer skin cells about every 27 days
Largest cell is female egg
Smallest cell in male body is sperm
Three hundred cells die every minute

Evolution of cells, Cell theory, Structure

Evolution of Cells
 
4.5 billion years ago
 
0.5 billion years ago
Cell theory
 
All living things are made up of cells
 
cell is the functional unit of life
 
All living cells come from pre-ex­isting cells
Cell structure
 
the cell is the basic unit of life and contains internal structures called organelles

Nucleus

Nucleus
 
Dark granule in the center of the cell
 
Stores genetic inform­ation
 
Controls cell activities through protein synthesis
 
Controls cell division
 
It is the site of DNA replic­ation and transc­ription
Nucleolus
 
This is the dark stained area in the nucleus
 
Made up of RNA
 
It has no membrane
 
Makes rRNA (ribosomal RNA) which then makes ribosomes
Nuclear Membra­ne/­Env­elope
 
Double layer of cell membrane, which contains very large pores
 
Pores allow RNA and proteins in and out of the nucleus
Chromatin
 
Densly coiled DNA wrapped around histone proteins
 
Contains the blueprint for all proteins in the body
 
Condensed into chromo­somes before cell replic­ation
Nucleo­plasm
 
Cytoplasm of the nucleus
 
Supports and suspends the contents of the nucleus
Mitoch­ondria
 
Furnace of the cell
 
Has double membrane, inner membrane is very folded = CIRISI­AE(­Inc­reased surface area)
 
Have their own DNA
 
Used to convert chemical energy in food into ATP
 
Performs Cellular respir­ation
Ribosome
 
Small dark granules made of rRNA
 
Site of protein synthesis
 
Make sure the correct order of amino acids in the protein chain
 
Sometimes attached to the rough er, so that proteins made can be easily exported
Polysome
 
Join up to make copies of the same protein
 
Produce proteins to only be used inside the cell
 

Types of Cells

Prokar­yotic
 
Pro=before
 
Karyot­ic=­nucleus
 
These were the first cells
 
Were primitive small had no defined nucleus (no nucleus membranes) and no membrane bound cell organells
 
They have ribosomes
Eukaryotic
 
eu=true
 
karyot­ic=­nucleus
 
modern cells
 
Have nucleus and membrane bound organells
 
Much larger up to 1000 longer.

Organelles

Organelles
 
Plasma Membrane
 
Universal structure same in each organism
 
Composed of a bilayer of phosph­olipids proteins embedded in it
 
Most organelles inside cell also have bilayer membrane
 
Model used to explain cell membrane is called fluid mosaic model
 
Select­ively permeable control what comes in and out of cell
 
does not let large, charged, or polar things through
 
Fluid Mosaic Model:The phosph­oli­pid­smove thus allowing small non-polar molecules to slip through
 
Phosph­olipid Bilayer = Double layered membrane
 
Glycol­ipi­ds:­Carbs attached to phosph­oli­pid­s.act as receptors
 
Glycop­rot­ien­s:Carbs attached to protei­ns.Act as receptors.
 
Integral Protei­ns:­assists specific larger and charged molecules to move in and out of cell.Can act as tunnels and change shape
 
Peripheral protei­ns:Only go through a part of the membrane or sit on top of another protein
 
Choles­ter­ol:­Reduces membrane fluidity reducing phosph­olipid moveme­nt.S­tops membrane from becoming solid at room temper­atures.
 
Cytosk­ele­ton­:Acts as framework gives cell shape.S­erves as monorail to transport organelles around the cell.

Rough Smooth ER

Endopl­asmic Reticulum
 
Network of sheets of cell membrane.
 
Er connects the nuclear membrane to the plasma membrane
 
Transport system
 
Two types of ER
 
Rough ER
 
Smooth ER
Rough ER
 
Attached ribosomes
 
Sometimes connected to nuclear membrane
 
Ribosomes make proteins put them in rER
 
Sometimes modified here
 
rER packages proteins in a vesicle and sends them to the Golgi Body
Smooth ER
 
No ribosomes
 
Makes lipids and steroids
 
Deotox­ifies harmful material or waste products
 
Lots of sER in liver cells and glands that make hormones

GolgiA­ppa­rat­usV­ess­Vac­uol­eLy­sos­ome­Cyt­osk­eleton

Golgi Apparatus
 
Made up of flattened saccules of cell membranes which are stacked loosely on top of each other
 
One side faces the ER and other faces plasma membrane
 
Usually vesicles at the edges of the golgi
 
To receive modify and tempor­arily store proteins and fats from the rough and smooth ER
 
These proteins are packaged into vesicles which pinch ff from the edges, and are distri­buted within the cell or shipped to the cell membrane for excretion
Vessicles
 
Storage sacks of the cell membrane
 
Smaller and are formed by pinocy­tosis (Cell drinking) at the plasma membrane or are made by the golgi body
 
Used to move substances around the cell that need to be separate from the cytoplasm
 
Stores food water and/or waste.
Vacuole
 
Larger and formed by phagoc­yto­es(Cell eating)
Lysosome
 
Double membraned vacuoles with hydrolytic (diges­tive) enzymes
 
Made by gogli body
 
Known as suicide sacs
 
Lysoso­me-­-Hy­dro­lysis
 
Attach to food vacuoles and digest their contents
 
Destroy old or malfun­cti­oning cell parts
 
Capable of destroying bacteria
Cytosk­eleton
 
Gives cell its shape and form anchors and supports cell organelles
 
Serves as monorail to transport organelles around the cell
 
Two components of cytosk­eleton microtubes microf­ila­ments
Microt­ubule
 
Larger than microf­ila­ments
 
Cylinder shaped and made of a coiled protein called tubulin
 
they are used to make cilia, flagella, centroiles and spindle fibers
 
Cilia & Flagella
 
Are hair like projec­tions, which use energy to produce moveme­nt/­loc­omotion
 
Move as the pairs of tubules slide against each other
 
Cilia are short and there are many of them.F­lagella are long and few
 
Made up of microt­ubles
 
Anchored to cell by a basal body
Centriole
 
Pair of basal bodies­(mi­cro­tub­ules) that grow spindle fibers
 
They attach to and move chromo­somes during mitosis
 
Found in animal cells only
Microf­ila­ments
 
Long and extremely thin protein fibres that occur in bundles made of 2 proteins called actin and myosin
 
Organelles more around the cytoplasm with the help of these
Cytoplasm
 
Watery gell it supports all organelles to provide water for all of the cells bioche­mistry
 
Mainly water with dissolved salts, proteins and other organic compounds.