Biology 3
Archaen Cells
Resemble bacterial cells Different because cells contain biochemicals.
ROUGH ER Endoplasmic Reticulum
Ribosomes give these membranes a roughed appearance
Transport proteins
embedded in the phospholipid bilayer create passageways through which water-soluble molecules and ions pass into or out of the cell
Light Microscopes
generates true color views of living or preserved cells light must pass through an object to reveal its internal features specimens must be transparent or thinly sliced to generate a good image - Compound Microscope uses two or more lenses to focus visible light through a specimen up to 1600 x and distinguished between objects at are 200 nano meters apart. - Confocal Microscope Enhances resolution by focusing white or laser light through a lens to the object. Image passes through a pinhole
Nucleus
most prominent organelle in most eukaryotic cells Contains DNA, an information molecule that specifies the "recipe" for every protein a cell can make
golgi apparatus
organelle sack of flat membrane-enclosed sacs that functions as a processing center. Proteins from ER pass through the series of Golgi sacs, they complete their folding and become functional. sorts and packages materials into vesicles, which move toward the cell membrane
Scanning electron microscope (SEM)
scans a beam of electrons over the surface of a metal coated, three dimiensional specimen. lower resolution than the TEM max magnification is 250,000 x
Nuclear Envelope
separates the nucleus from the cytoplasm
SMOOTH ER
Adjacent to the Rough ER Synthesizes lipids Houses enzymes that detoxify drugs and poisons
Study of cells began
1660
Cell wall
surrounds the cell membrane of most bacteria, protecting the cell and preventing it from bursting if it absorbs too much water What surrounds the cell membrane of most bacteria and provides structure and protection?
Flagella
tail-like appendages that enable these cells to move. Anchored in the cell wall and underlying cell
Cells have features in common
DNA - Cell's genetic information
Nucleolus
Dense spot that assembles the components of ribosomes. Ribosomal sub units leave the nucleus through nuclear pores. Come together in the cytoplasm to form complete ribosomes
Peroxisomes
Eukaryotic Cells Organelles that containg several types of enzymes that dispost of toxic substance
Cytoplasm
Fluid that occupies much of the volume of a cell
Phospholipid
Glycerol bonds to only two fatty acids; the third carbon binds to a phosphate group attached to additional atoms.
Nuclear pores
Holes in the double-membrane (nuclear envelope) MRNA molecules exit the nucleus through
Phospholipid bilayer
two layered, sandwichlike structure, the hydrophilic surfaces (the bread) are exposed to the watery medium ourside and inside the cell Hydrophobic tails face each other on the inside of the sandwich.
Lysosomes
Organelles containing enzymes that dismantle and recycle food particles, captured bacteria, worn out organellas and debris Enzeyme LYSE or cut apart their substrates
Enzymes
Proteins facilitate chemical reactions that otherwise would proceed too slowly to sustain life
Nucleoid
The area withing the cytoplasm of a prokaryotic cell where the circular DNA molecule is found is called the nucleoid and is not bounded by a membrane.
Phospholipid
The cell membrane is composed of a type of lipid molecule called ___, which has two fatty acids and a phosphate group extending from a glycerol molecule
endomembrane system
The internal membranes of several organelles are interconnected and form the ___ system of a eukaryotic cell.
Domain Eukarya
The ribosomes of domain Archaea are most similar to those of _____
Cells
The smallest unit of life that can function independently
Nucleoid
area where cell's circular DNA molecule congregates
Receptor proteins
bind to hormones and other molecules outside the cell and trigger a response into the cell
Organelles (little organs)
compartments that carry out specialized functions Examples: nucleus, mitochondria & chloroplasts keep related biochemicals & structures close enough to make them function efficiently
Eukaryotes EU (True)
Cells that contain a nucleus
Transport Proteins
embedded in the phospholipid bilayer create passageways through which water soluble molucules and ions pass into or out of the cell.
Cell Membrane (Plasma Membrane)
forms a boundary between the cell and its environment
Bacterial nucleoid
is not bound by a membrane
Fluid Mosaic
Cell membrane diverse molecules (pieces of the mosaic) drift freely among the phospholipids.
Recognition proteins
Carbs attached to cell surface proteins serve as "name tags" that help the body's immune system recognize its own cells
Compartmentalization
Cell maintains high concentrations of each biochemical only in certain organelles, not throughout the entire cell.
Robert Hooke
Melted strands of grass to create lenses. used to look at corks.
How are bacteria and archaea similar to and different from each other?
Membrane lipids Composition of cell walls ribosomes
Adhesion proteins
Membrane proteins enable cells to stick to on another
Transmission Electron Microscope (TEM)
Sends a beam of electrons through a very thin slice of a specimen. Can magnify up to 50 million x and distinguish between objects less than 1 angstrom apart
Roles that Membrane plays in cells
Separates cytoplasm form outside of cell Cells surface also transports substances into and out of the cell receives & responds to external stimuli Eukarytic cell, internal membranes enclose the organelles
Prokaryotic Pro (before) Karyon (Kernel, referring to the nucleus)
Simplest and most ancient forms of life Organisms whose cells lack a nucleus
Ribosomes
Structures that manufacture proteins
Rudolf Virchow
Added 3rd component to Cell Theory in 1855
endomembrane system Cell Parts Lysosomes Golgi apparatus Nuclear envelope endoplasmic reticulum
Internal membranes form: nuclear envelope endoplasmic reticulum Golgi apparatus lysosomes vacuoles cell membrane Organelles of the endomembrane system are connected by small "bubbles" of membrane that can pinch off of one organelle, travel within the cell, and fuse with another.
Vesicles
Membranous spheres that transport materials inside the cell as part of the endomembrane system.
Endoplasmic reticulum Endoplasmic "within the cytoplasm" Reticulum "network"
Network of membranes originating at the nuclear envelope and winding through the cell.
Mitochondria
Organells that use a process called cellular respiration to extract this needed energy from food
Cells
Originally had two main components: 1. All organisims are made of one or more cells 2. the cell is the fundamental unit of all life. 3. added 1855 - Cells come from preexisting cells