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Complete summary of the book: 'Human physiology, an integrated approach'
Complete summary per chapter of the book 'Human physiology, and integrated approach'
[Meer zien]Voorbeeld 4 van de 59 pagina's
Voorbeeld 4 van de 59 pagina's
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12 beoordelingen
Door: frederiekepijl • 1 jaar geleden
Enkel tekst, zonder plaatjes, waardoor het lastig te begrijpen is helaas
Door: dccharger • 3 jaar geleden
Door: kylianmbappe • 3 jaar geleden
Door: jimle • 4 jaar geleden
Very good review but make sure you add what your profs emphasis during lectures as well
Door: rtganji • 4 jaar geleden
Door: carlijnpos • 4 jaar geleden
Door: karlijnveldmaat • 4 jaar geleden
Voorbeeld van de inhoud
Chapter 1 - Introduction to physiologydinsdag 15 november 2016
18:18
Physiology is the study of the normal functioning of a living organism and its component parts,
including all its chemical and physical processes.
Emergent properties = properties that cannot be predicted to exist based only on knowledge of the
system's individual components.
Four systems exchange materials between the internal and external environments:
The respiratory (pulmonary) system; exchanges gases
The digestive (GI) system; takes up nutrients and water and eliminates wastes
The urinary (renal) system; removes excess waste material and water
The reproductive system; produces eggs or sperm
Themes of physiology:
1. Structure and function across all levels or organization
2. Energy transfer, storage and needs
a. Living organisms need energy
3. Information flow, storage, and use within single organisms and within a species of organism
a. Information flow coordinates body function
4. Homeostasis and the control systems that maintain it
a. Maintains internal stability
Homeostasis is the stability of the body's internal environment, so the stability of the extracellular
fluid compartment.
To maintain homeostasis, the body must maintain mass balance. The law of mass balance says that if
the amount of a substance in the body is to remain constant, any gain must be offset by an equal
loss.
The amount of substance in the body is also called the body's load.
Total amount of substance x in the body = intake + production - excretion - metabolism
Excretion is defined as the elimination of material from the body, usually through the urine, feces,
lungs or skin.
Mass flow = concentration of x * volume flow
Clearance is usually expressed as a volume of blood cleared of substance x per unit of time. For this
reason clearance is only an indirect measure of how substance x is eliminated.
To maintain homeostasis, the human body monitors certain key functions, such as blood pressure
and blood glucose concentrations, that must stay within a particular operating range if the body is to
remain healthy.
These important regulated variables are kept within their acceptable range by physiological control
mechanisms that kick in if the variable ever strays too far from its setpoint.
All control systems have three components: An input signal, a controller, or integrating centre, and
an output signal.
There are two basic patterns of control mechanisms: local control, and long-distance reflex control.
The simplest for of control is local control, which is restricted to the tissue or cell involved.
,We will use reflex control to mean any long-distance pathway that uses the nervous system,
endocrine system or both.
Negative feedback loops stabilize the regulated variable and thus aid the system in maintaining
homeostasis. Negative feedback loops can restore the normal state but cannot prevent the initial
disturbance.
-> Negative feedback loops are homeostatic, positive feedback loops are not.
Feedforward control: A few reflexes have evolved that enable the body to predict that a change is
about to occur and start the response loop in anticipation of the change.
Regulated variables that change in a predictable manner are called biological rhythms. Those that
coincide with light-dark cycles are called circadian rhythms.
Chapter 2 - Molecular interactions
zondag 5 februari 2017
20:41
Organic molecules associated with living organisms are also called biomolecules.
There are four major groups of biomolecules: carbohydrates, lipids, proteins and nucleotides.
Conjugated proteins are protein molecules combined with lipids to form lipoproteins.
Proteins combined with carbohydrates (glycosylated) become glycolipids.
Carbohydrates: (CH2O)n
Nucleotides are biomolecules that play an important role in energy and information transfer.
-> Like ATP, ADP and (cyclic)AMP.
Polymers of nucleotides are nucleic acids like RNA and DNA which store and transmit genetic
information.
Electrons have four important roles in physiology:
1. Covalent bonds. Electrons shared between atoms form strong covalent bonds that create
molecules. So the ability to bind with other elements.
2. Ions. Ions are the basis for electrical signalling in the body.
3. High-energy electrons. The electrons in certain atoms can capture energy from their
environment and transfer it to other atoms. This allow the energy to be used for synthesis,
movement, and other life processes.
4. Free radicals. Free radicals are unstable molecules with an unpaired electron. They are
thought to contribute to aging and to the development of certain diseases, such as some
cancers.
Polar molecules can be said to have positive and negative ends, or poles. Certain elements have a
strong attraction for electrons and are often found in polar molecules.
A nonpolar molecule is one whose shared electrons are distributed so evenly that there are no
regions of partial positive or negative charge.
Ionic bonds, hydrogen bonds and van der Waals forces are noncovalent bonds. They play important
roles in many physiological processes, including pH, molecular shape, and the reversible binding of
molecules to each other.
,Ionic bonds. Also known as electrostatic attractions, result from the attraction between ions with
opposite charges.
Hydrogen bonds. The oppositely charged regions in polar molecules are attracted to each other.
Hydrogen bonds may occur between atoms in neighbouring molecules or between atoms in different
parts of the same molecule.
Van der Waals forces are weak, non-specific attractions between the nucleus of any atom and the
electrons of nearby atoms.
Hydrophobic substances are usually nonpolar molecules that cannot form hydrogen bonds with
water molecules.
A molecule's shape is closely related to its function. Molecular bonds play a critical role in
determining molecular shape.
Globular proteins have amino acid chains that fold back on themselves to create a complex tertiary
structure containing pockets, channels or protruding knobs.
In addition to noncovalent bonds, covalent disulfide (S-S) bonds play an important role in the shape
of many globular proteins.
Proteins play important roles in so many cell functions that they can be considered the 'workhorses'
of the body. Most soluble proteins fall into one of seven broad categories:
1. Enzymes; biological catalysts that speed up chemical reactions
2. Membrane transporters; help move substances back and forth between the intracellular and
extracellular compartments
3. Signal molecules
4. Receptors
5. Binding proteins
6. Immunoglobulins; antibodies
7. Regulatory proteins; turn cell processes on and off or up and down
-> They all bind to other molecules through noncovalent interactions. The binding, which takes place
on the protein molecule called a binding site, exhibits properties: specificity, affinity, competition and
saturation.
Specificity = The ability of a protein to bind to a certain ligand or a group of related ligands.
Affinity = The degree to which a protein is attracted to a ligand.
Closely related proteins whose function is similar but whose affinity for ligands differs are called
isoforms of one another.
Some proteins are inactive when they are synthesized in the cell. Before such a protein can become
active, enzymes must chop off one or more portions of the molecule. Protein hormones and enzymes
are two groups that commonly undergo such proteolytic activation.
This activation of some proteins requires the presence of a cofactor, which is an ion or small organic
functional group.
A factor that influences either protein binding or protein activity is called a modulator. The
modulator either changes the protein's ability to bind the ligand or it changes the protein's activity or
tis ability to create a response.
Competitive inhibitors are reversible antagonist that compete with the customary ligand for the
binding site.
Allosteric modulators bind reversibly to a protein at a regulatory site away from the binding site, and
by doing so change the shape of the binding site.
, Covalent modulators are atoms or functional groups that bind covalently to proteins and alter the
proteins' properties.
--> Like phosphorylation
Once the concentration of ligand molecules exceeds a certain level, the protein molecules have no
more free binding sites. The proteins are fully occupied, and the rate reaches a maximum value. This
condition is known as saturation.
Chapter 3 - Compartmentation: Cells and tissues
maandag 6 februari 2017
11:53
A tissue lining called the peritoneum lines the abdomen and surround the organs within it; stomach,
intestines, liver, pancreas, gallbladder and spleen.
The interior of any hollow organ is called its lumen.
The extracellular fluid subdivides further into plasma, the fluid portion of the blood, and interstitial
fluid, which surrounds most cells of the body.
The dividing wall between ECF and ICF is the cell membrane.
The visible membranes are tissues: thin, translucent layers of cells.
Cell membranes are the outer membranes of cells. These membranes consists of microscopic double
layers of phospholipids with protein molecules inserted in them.
The general functions of the cell membrane include:
1. Physical isolation; separates the ICF from the ECF.
2. Regulation of exchange with the environment; controls the entry of ions and nutrients into
the cell, the elimination of cellular wastes, and the release of products from the cell.
3. Communication between the cell and its environment; it contains proteins that enable the
cell to recognize and respond to molecules or to changes in its external environment.
4. Structural support; proteins in the membrane hold the cytoskeleton. Membrane proteins
also create specialized junctions between adjacent cells or between cells and the extracellular
matrix, which is extracellular material that is synthesized and secreted by the cells.
Micelles are small droplets with a single layer of phospholipids arranged so that the interior of the
micelle is filled with hydrophobic fatty acid tails. Micelles are important in the digestion and
absorption of fats in the digestive tract.
Liposomes are large spheres with bilayer phospholipid walls. This arrangement leaves a hollow
center with an aqueous core that can be filled with water-soluble molecules.
Cholesterol molecules, which are mostly hydrophobic, insert themselves between the hydrophilic
heads of phospholipids. Cholesterol helps make membranes impermeable to small water-soluble
molecules and keeps membranes flexible over a wide range of temperatures.
During differentiation, only selected genes activate, transforming the cell into a specialized unit. In
most cases, the final shape and size of a cell and its contents reflect its function.
The cytoplasm includes all material inside the cell membrane, except for the nucleus. The cytoplasm
had four components:
1. Cytosol; it contains dissolved nutrients and proteins, ions, and waste products.
2. Inclusions; particles of insoluble materials.
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