Chapter 1 | Components of the Cell - Plasma Membrane

Cell

What is the basic unit of life?

All organisms are composed of cells, Cells are the basic unit of life, and they arise from pre existing cells

The modern cell theory states that…

Cell

Living, structural, and functional unit

Cell Biology/Cytology

The study of cellular structures and functions

Cell Division

The process in which cells arise from existing cells

Nucleus, Cytoplasm, Plasma Membrane

The three major parts of the cell

Plasma Membrane

The flexible outer part of the cell

Fixed Structure

The plasma membrane is not stable, as it is not a __

Plasma Membrane

Regulates the flow of material sin and out of the cell

Plasma Membrane

Communicates the cell to other neighboring cells

Plasma Membrane

Outer covering of the whole cell

Cytoplasm

Consists of all cellular components

Cytoplasm

Where all cellular reactions take place

Cytosol and Organelles

The two compartments of the cytoplasm

Cytosol

Gelatin-like fluid that surround the organelles

Organelles

Specialized sub-units in a cell that carries out certain functions.

Organelles

Called "little organs"

Nucleus

Houses the DNA (genetic material)

Nucleus

Contains Chromosomes, which contains genes

Genes

Controls most aspect of cellular structure and function.

Genes

Where hereditary information is stored

Nucleus

Is the control center of the cell

Nucleus

near the center of a cell

Plasma Membrane

Is a lipid Bilayer

Plasma Membrane

Serves as the basic structural framework of the cell

Fluid Mosaic Model

Explains the structure of the cell membrane

Phospholipids

Makes up 75% of the plasma membrane and is composed of phosphorous

Cholesterol

Makes up 20% of the plasma membrane and is a steroid with a hydroxyl group

Glycolipids

Makes up 5% of the plasma membrane and is a carbohydrate group

Semi-Permeable Membrane

It means it only allows select things to enter the cell

Amphipathic

Having both sides polar and non-polar

Non-Polar

Lipids are, __, they cannot be dissolved in water

Hydrophobic, Hydrophilic

The phospholipids are made up of ____ tail and ____ head

Cholesterol Molecule

A weakly amphipathic molecule

Polar

The hydroxyl group is ___

Non-Polar

The steroid ring and hydrocarbon tail are

Glycolipids

Appears on the side that faces the extracellular fluid

Glycoproteins

Molecules that comprise protein and carbohydrate chains

Integral Proteins

They are imbedded in the phospholipid bilayer

Integral Proteins

Strong hydrophobic interactions with lipid bilayer

Transmembrane Protein

Spans the entire lipid bilayer

Peripheral Proteins

Not firmly embedded in the membrane

Peripheral Proteins

It is attached to the polar heads of membrane lipids/integral proteins

Membrane Fluidity

Allows interactions to occur

Membrane Fluidity

Enables movement in membrane components responsible for cellular process

Membrane Fluidity

Allows the lipid bilayer to self heal/seal when punctured

Membrane Permeability

Permits the passage of substances

Permeable, Impermeable, Slightly Permeable

The lipid bilayer is __ to non polar, __ to large uncharged particles, and __ to water, urea and the such

Water, Urea and Waste Products (Amino Acids)

What are slightly permeable in the cell membrane

Passive transport

The movement of substances that DO NOT require cellular energy

Diffusion

Movement if molecules due to molecular kinetic energy

Diffusion

Movement of particles from an area of High Concentration to an area of Low Concentration

Simple Diffusion

Passive movement of substances without the help of membrane transport proteins

Facilitated Diffusion

Passive movement of a substance through the channels or carriers

Osmosis

Passive movement of water molecules from high solute concentration to low concentration

Isotopic, Hypotonic, Hypertonic

The three tonicities of a cell

Isotonic

The cell remains the same size

Hypotonic

The cell will grow

Hypertonic

The cell with shrink

Aquaporins

Channel proteins used to transport big water molecules

Concentration Gradient

The difference in concentration from one part to another

Along, Against

Passive Transport moves ___ the concentration Gradient and Active Transport moves __ it.

Active Transport

Movement that require energy

Primary and Secondary Transport

The two kinds of Active Transport

Active Transport and Transport in vesicles

The two kinds of active process

Primary Transport

The direct use of metabolic energy that comes from hydrolysis of the ATP

Hydrolysis

is the breaking down of water

Secondary Transport

These use the energy from the Primary Transport, recycling it

Transport in Vesicles

Movement happens in vesicles that require ATP

Vesicles

Small pouches that transport molecules

Endocytosis, Exocytosis, Transcytosis

The three kinds of transport in vesicle

Endocytosis

Movement of substance into the cell

Receptor Mediated

Ligand-receptors that triggers infolding of a Clathrin pit that forms a vesicle containing Ligands

Ligands

Substance that bind to receptors

Phagocytosis

"Cell Easting", engulfing of pseudopods

Bulk Phase Endocytosis

"Cell Drinking", movement of extracellular fluid

Pinocytosis

Allows small amounts of water to enter the cell

Exocytosis

Movement of substances out of the cell in secretary vesicles that fuse with the plasma membrane

Transcytosis

Movement of substance as a result of endocytosis on one end and exocytosis on the opposite end