Physiology

• Cell


  The structural and functional unit of life. The human body is composed of trillion cells.
• Functions of Human cell

  • Provide structure and support
  • Facilitate growth through mitosis
  • Passive and active transport
  • Production of energy
  • Metabolic reaction
  • Reproduction
• Structure of The Cell

  • Plasma membrane (cell membrane)
  • Cytoplasm
  • Nucleus
• Plasma membrane


  A thin flexible barrier that separates the inside of the cell from the environment outside the cell and regulates what can pass in and out of the cell
• Cytoplasm


  Made up of a jelly-like fluid (called the cytosol) and other structures (called organelles) that surround the nucleus
• Nucleus


  The major organelle, separated from the cytoplasm by a nuclear envelope (membrane). It contains the DNA (genes) that is necessary for reproduction and cell growth.
• Cytoplasm's organelles


  • Endoplasmic reticulum
  • Golgi apparatus
  • Lysosomes and peroxisomes
  • Mitochondria
  • Ribosomes
• Endoplasmic reticulum


  Helps process molecules created by the cell
• Golgi apparatus


  Packages molecules processed by the endoplasmic reticulum to be transported out of the cell
• Lysosomes and peroxisomes


  Digest foreign bacteria that invade the cell
• Mitochondria


  Convert energy from food into a form that the cell can use
• Ribosomes


  Process the cell's genetic instructions to create proteins
• Cell membrane


  Consisting mainly of phospholipid (fat) molecules and proteins, where a double layer of phospholipid molecules
• Plasma membrane


  Selectively permeable or semi-permeable, meaning that only certain substances which are able to pass through the membrane
• Transport across plasma membrane

  • Active Transport
  • Passive Transport (Diffusion)
• Active Transport


  The transport of molecules with the active assistance of a carrier that can transport the material against a natural concentration gradient. This process requires energy.
• Passive Transport (Diffusion)


  The movement of molecules from areas of high concentration to areas of low concentration via a carrier. This process does not require energy.
• Cell Division


  • Mitosis
  • Meiosis
• Cell junctions


  A class of cellular structures consisting of multiprotein complexes that provide contact or adhesion between neighboring cells or between a cell and the extracellular matrix
• Types of Cell Signaling

  • Endocrine Signaling
  • Paracrine Signaling
  • Autocrine Signaling
  • Contact-Dependent Signaling
  • Synapse signaling
• Endocrine Signaling


  In the body, many endocrine cells are located in endocrine glands, such as the thyroid gland, the hypothalamus are usually produce a slower response but have a longer-lasting effect.
• Paracrine Signaling


  Signals that act locally between cells that are close together. These types of signals usually elicit quick responses that last only a short amount of time.
• Autocrine Signaling


  Autocrine signals are produced and bind to the ligand that is released. This type of signaling often occurs during the early development of an organism
• Contact-Dependent Signaling


  In contact-dependent signaling, cells must physically interact to initiate cell signaling.
• Synapse signaling


  Is the transfer of signals across synapses between nerve cells.
• The sympathetic nervous system is responsible for the fight or flight response.
• CVS


  Cardiovascular System
• CVS


  • Consists of the heart and blood vessels including arteries, veins and capillaries
• Heart


  • Hollow muscular organ, pyramidal in shape, lies within the pericardium in the mediastinum
  • Connected at its base to the great blood vessels but otherwise lies free within the pericardium
  • Weight in adult man is about 300g, slightly less in women
  • Volume of each chamber is about 80-120 cm3
  • Left ventricle pumps about 70 cm3 in each heartbeat, 10 cm3 of blood remains
• Cardiac Muscle


  • Has the character of rhythmicity (contraction followed by relaxation then the cycle repeated)
  • Has the character of conductivity as each cardiac muscle fiber is divided into many branches and lies beside the branches of other fibers
  • Hearts receive nutrient and O2 to supply myocardium via coronary arteries (Right and left) from the sinuses behind two of the cusps of the aortic valve at the root of the aorta, and they are patent throughout the cardiac cycle
• Chambers of the heart

  • Divided by vertical septa into two halves, the right and left atria and right and left ventricles
  • The right atrium lies anterior to the left atrium and the right ventricle lies anterior to the left ventricle
• Valves of the heart

  • There are valves between each atrium and corresponding ventricle, allowing blood to pass from atrium to ventricle only and prevent the opposite direction except when there is abnormal dilatation or valve damage
  • The opening between left atrium and left ventricle is called the left atrio-ventricular opening, and the valve between them is called the bicuspid valve (mitral valve)
  • The opening between right atrium and right ventricle is called the right atrio-ventricular opening, and the valve between them is called the Tricuspid
  • Between left ventricle and the aorta there is a valve called the Aortic valve (tricuspid), it lies at the sternal end of 2nd right rib
  • Between right ventricle and pulmonary arteries there is a valve called the pulmonary valve (tricuspid), it lies at the sternal end of left 2nd inter costal space
  • The blood from each lung through two pulmonary veins go to the left atrium (these blood is oxidized), there is no valve between these veins and left atrium
  • The blood in the right side of the heart is deoxidized while that in the left side is oxidized
• The heart as a pump

  • Each ventricle pumps about 70 cm3 in each cardiac beat, this volume is called stroke volume
  • The heart is beating about 70 times per minute (heart rate)
  • Cardiac output, which is the volume of blood pumped by each ventricle within one minute, is equal to heart rate multiplying by stroke volume
  • At rest each ventricle pumps about 70x70 =4900 cm3 in each minute (about 5 liters of blood/minute)
  • The whole blood is circulated once every minute, while really some blood may circulate faster or slower than that
  • In exercise the heart rate and stroke volume increase and as a result the cardiac output will be increased
• Heart nutrition


  • The heart receives its own supply of blood from a network of arteries, called the coronary arteries
• Electrocardiogram (ECG)


  • The heart beat spread associate with change in electrical voltage, which can be recorded from a place away from the heart and this record
  • The changes of the voltage is very low but it was magnified and record by a machine called electrocardiograph which record all the changes during cardiac cycle (waves), and complexes so p-wave related to atrial contraction followed by a complexes (QRST) which consist of many waves which related to ventricular contraction
• Normal ECG


  • QRS wave is result of reaching heart beat pulse to different part of ventricle in different time, Q-wave not always present while T-wave result from relaxation of parts of heart before others
  • If any of ventricle not give complete voltage, these will be seen in S-T segment and occur in coronary arteries insufficiency as in ischemic heart disease, myocardial infarction and coronary thrombosis, and this segment will be elevated in anterior coronary thrombosis and suppressed in posterior coronary thrombosis
• Ischemic heart disease


  • Anterior coronary thrombosis
  • Posterior coronary thrombosis
• Heart Sounds


  • The main normal heart sounds are the first heart sound (S1) and the second heart sound (S2)
  • The third heart sound (S3) can be normal, at times, but may be pathologic
  • A S4 heart sound is almost always pathologic
• Murmur


  • A murmur is due to turbulence of blood flow and can, at times, encompass all of systole or diastole
  • Types of murmurs include: Systolic murmur - occurs during a heart muscle contraction, Diastolic murmur - occurs during heart muscle relaxation between beats, Continuous murmur - occurs throughout the cardiac cycle
• Cell


  The structural and functional unit of life. The human body is composed of trillion cells.