Anatomie (Memorisation)/(Improved notes)

Atoms -) Molecules -) Organelle -) Smooth muscle cell -) Smooth muscle tissue -) Smooth connective tissue -) Epitheleal tissue -) Organs (which are made up of tissue)

Activities of the cell are determined by their shape and size

Over 200 different types of human cells - they differ in different shapes, sizes, sub cellular components, functions

All cells have common structures - Human cells have three basic parts Plasma Membrane, Cytoplasm plasm, Nucleous.

(Note the mysocin is what detaches the ATP

Composants of cells and their 1)description/2)Functions

  • Plasma Membrane: 1) Made of a double layer of lipids where proteins pass through 2) It serves as a barrier and a method of transport

  • Mitochondria: 1) Rodlike inner membrane (looks like green beans) 2) Site of ATP synthesis , power house of the cell

  • Ribosomes: 1) subunit that consists of ribosomal RNA and proteins 2) Site of protein synthesis

  • Rough endoplasmic reticulum: 1) Membranous system cooling troughs the cytoplasm 2) Synthesizes phospholipids while helping with transport

  • Smooth endoplasmic reticulum: 1)Membranous system without ribosomes 2) Site of lipid and steroid synthesis and drug detoxification

  • Golgi Apparatus: 1) A group of enclosed membranes and vesicles 2) Packages, modifies and segregates proteins from secretion from the cell.

  • Peroxisomes: 1)Membranous sacs of catalase and oxidase enzymes 2) The enzymes detoxify a number of toxins

  • Lysosomes: 1) Membranous sacs filled with acid hydrolase 2) Sites of intracellular digestion

  • Microtubules: 1) cylindrical structures monad of tubulars proteins 2) Support the cell and give it’s shape

  • Microfilaments: 1) Fine filament composed of protein actin 2) involved in muscle contraction and other intercellular movements

  • Intermediate filaments: 1) Proteins fibres; composition varies 2) resists mechanical acting on the cell walls

  • Centrioles: 1) Composed of 9 triplets of microtribules 2) Organise microtribules to help during mitosis (cell division)

  • Cilia: 1) Short cell-surface projection 2)Propels substances across the cell surface

  • Flagellum: 1)Same as cilia but longer 2) Propels the cell

  • Microvilli: 1) Tubular extension of the plasma membrane 2) increase surface area for absorption

  • Nucleus: 1) Largest envelope of the nucleus 2) Control centre of the cell / responsible for transferring genetic information and giving the instructions for protein synthesis

  • Chromatin: Granular shape composed of DNA and historines proteins 2) DNA constitutes the gene

Individual human cells are specialized, each type has a specific function

Types of tissues and examples:

  • Nervous tissue: Brain, spinal cord

  • Muscle tissues: contraction, muscles of the heart

  • Epithelial tissues: Skin, lining of digestion track

  • Connective tissues: Bones, tendons

Epithelial tissues main purpose are:

  • Protection

  • Filtration

  • Absorption

  • Excretion

  • Secretion

  • Sensory reception

The ways to identify different Epitheleal cells are by its shape (ex. Squamous, cuboidal, columnar) and by its layers (ex. Simple epithelia , stratified )

Glandular epithelia is classified by their site of product release (endocrine or exocrine) And by the number of cells forming in the glands (unicellular or multicellular)

Endocrine gland release the hormones in the blood that are ductless and Exocrine releases the products in the ducts (mucous, sweat, etc)

Multicellular glands are classified by types of secretion and structure.

Such as simples glands or compound glands

Types of secretion is:

Merocine: most comme, secrete product by exocytosis (pancreas, salivary glands)

Apocrine: accumulates products within then apex Pinches off (controversial if it exists in humans)

Holocrine: accumulates produts within then ruptures. (Sebeaceous glands)

5 major types of CT: mesenchyme, Ct proper, cartilage, bone and blood

There main functions are:

  • Binding or support

  • Protection

  • Insulation

  • Storage

  • Transportation

Structural organization and elements of CT in general

  • Ground substance

  • Fibers

  • Cells

  • Cartilage

Plasma/Cell membrane acts as an active barrier that separates intracellular fluid (ICF) and the extracellular fluid (ECF). (It’s a filtration)

It’s selectively permeable (only allows certain things in)

Communication site of cell to cell interaction

Structure of plasma membrane:

Consists of membrane lipid, membrane proteins, fluids mosaic, sugars (glycolax) and form cell junctions

Membranes lipids:

75% phospholipids (phosphate heads are hydrophilic) (because they are polar charged) and (fatty acid tails no charge that are hydrophobic (due to acid))

5% glycolipids (sugars)

20% cholesterol to increase membrane stability

Membrane proteins

  • Half the mass of the plasma membrane

  • Allow cell communication with environment

  • Most have specialized membrane function

  • Some float freely and some are tethered to intracellular structures

  • Functions: transport, cell to cell regeneration, receptors, attachment to cytoskeletons, enzymatic activity, cell to cell joining

  1. Integral proteins: firmly inserted into membrane That are transmembrane proteins have both hydrophobic and hydrophilic regions

  2. Peripheral proteins: loosely attached to intergeral proteins , includes filament on intracellular surface usefor plasma membrane support

Membrane carbohydrates and glycolax

Consists of sugars And every cell has a type of sugar coating to help recognize who is self and who is non self

Cell junctions

3 types of cell junctions

  1. Tight junctions: impermeable junctions

  2. Desmosomes: Anchoring junctions

  3. Gap junction: Communicating junctions

Plasma membrane is selectively permeable, hydrophobic barrier between flui and cytoplasm

Membrane transport is separated in to 2 Active and passive for the extra cellular fluid. Passive requires no ATP while Active requires ATP. Passive can do diffusion and Carrier-mediated transport. While Active can do carrier-mediated transport and vesicular.

Passive transport:

  • Diffusion

All types involve diffusion which is the natural movement of molecules from areas of high concentration to area of low concentration. Also known as going down the concentration gradient

What affects the speed of diffusion:

  1. Concentration gradient

  2. Temperature

  3. Molecular size

What determines whether something can or can’t cross the plasma membrane during diffusion is lipid soluble and non polar substances. In other words very small molecules can pass through.

There are 2 types of diffusion

  1. Simple diffusion: Nonpolar and lipid soluble substances diffuse directly through the phospholipid ;layer with no Carrier needed if lipid soluble.

  2. Facilitated diffusion: Larger or water soluble or polar molecules can cross only if they have a carrier with them.

The 2 types of carriers used in facilitated diffusion are carrier-mediated and channel-mediated

The difference is one binds to protein carriers and the other moves through water filled channels.

Water and solutes are forced through a membrane wall by the hydrostatic pressure (filters)

Osmosis: diffusion of solvent (not molecules) such water across a selectively permeable membrane (basically osmosis only works if there is a different concentration on two different side which allows water to flow

Each different particles has a different osmolarity level

Hypertonic solutions pull water out and hypotonic solutions rehydrate

ACTIVE TRANSPORT:

Requires ATP because we’re going against the concentration gradient which needs energy.

The two major membrane process are:

  • Active transport

  • Vesicular transport

Both require ATP because:

  • solute is too large for Chanels

  • Solute is not lipid soluble

  • Solute is not able to move down the concentration gradient

Primary and secondary active transports: Primary gets its ATP directly from hydrolysis. And secondary only get its ATP from indirect ionic gradients

Best example of Active transport is the NA+ K+ pump

Ratio is 3NA+ for 2K+ and it does this to give maintenance to this pump

Vesicular transport is the transport of large particles and fluid across the membrane's

The Na+ K+ pump are able to move solutes against the electrochemical membrane supplied by ATP

The nervous system is set into 2 parts

  • Central nervous system (CNS)

  • Peripheral nervous system (PNS)

The PNS system is also separated into 2 parts

  • Sensory (afferent) division

  • Motor (efferent) division

Efferent division is also separated into 2 parts

  • somatic nervous system Peripheral

  • automatic nervous system (ANS)

The ANS is also separated into 2 different categories

  • Sympathetic division

  • Parasympathetic division

Nervous tissue is superheated into 2 types

Neuroglia: (glia cells) small cells that surround and wrap delicate neurons

Neurons: (nerve cells) excitable cells that transmit signals

Neurons have threee function region receptive region, conducting region

Definitions:

  • Cell: Structural and functional unit of life

  • Tissues: Groups of cells that perform a similar function

  • Histology: study of tissues

  • Epithelial tissue: A sheet of cells that forms a body

  • Gland: one or more cells that makes and secretes an aqueous fluid called secretion

  • Osmolarity: the total concentration of all solute particules in a solution

  • Tonicity: ability of a solution to change shape and (or plasma membrane tension)

  • Symporter: transports 2 different substances in the same direction

  • Antiporter transports one substance into cell while transporting a different substance.