Cardiovascular (Blood)

• What is the functions of blood?


  Transportation, regulation, protection.
• What does the blood transport?

  Oxygen, Carbon dioxide, Nutrients and Waste.
• What does the blood regulate?

  pH, Body temperature and Fluid Volume
• What does the blood protect against from?

  Blood loss and infection
• What are the physical characteristics of blood?Fluid connective tissue 

  • More viscous (thicker) than water
  • 38 °C
  • Narrow pH range: 7.35 – 7.45
  • 4 – 6 litres (depending on sex and body size)
• What are the two main components of blood?

  Blood Plasma (55%) and Formed elements (45%)
• Blood Plasma (55%)

  • Liquid extracellular matrix
  • Largely water
  • Plasma proteins  - albumin most numerous    - fibrinogen (essential in blood clotting)
  • Other solutes    - electrolytes (Na+, Ca2+, Mg2+, Cl-, HCO3-)    - nutrients (amino acids, glucose, vitamins, minerals)    - gases (oxygen, carbon dioxide, nitrogen)    - regulatory substances (hormones, enzymes)    - waste products (urea, bilirubin, ammonia)
• 2. Formed Elements (45%)

  • Cells and cell fragments
  • Erythrocytes (red blood cells)
  • Leukocytes (white blood cells)
  • Platelets
• Blood is transported through the vessels to deliver oxygen and nutrients to every cell and to remove the carbon dioxide and waste.
• What is the name for red and white blood cells

  Erythrocytes (Red), Leukocytes (white)
• What is Systolic Blood Pressure?

  Maximum blood pressure during contraction of the ventricles. Pressure of arteries during ventrical
• What is Diastolic blood pressure?

  Minimum blood pressure recorded just prior to the next contraction (relaxation)
• What is the difference between arteries and veins?

  Arteries carry blood away from the heart (rounder). Veins carry blood towards the heart (Collapsed shape).
• What is blood pressure?

  Constriction of arterioles increases resistance, causes a decrease in blood flow to downstream capillaries and a larger decrease in blood pressure.
• Where does oxygen-rich blood go?

  Oxygen-rich blood enters the heart from lungs and goes out to body. Oxygen-poor blood enters heart from body and goes out to lungs.
• Layers of heart wall.

  Pericardium (Protective membrane), Epicardium (Connective tissue), Myocardium (Pump?) and Endocardium (Thin Connective tissue).
• What is Pulmonary Circulation?


  Process of External Respiration. Deoxygenated blood flows into lungs, absorbs oxygen from alveoli and release carbon dioxide to be exhaled.
• What is systemic circulation?

  Internal Respiration. Oxygenated blood flows into capillaries throughout the body allowing oxygen from blood to diffuse into cells and absorb carbon dioxide from tissues.
• What is an ECG?

  Electrocardiogram used in recording of the heart's electrical activity through repeated cardiac cycles
• ECG : P waves

  Electrical depolarisation of the atria
• ECG: QRS Wave


  Depolarisation of ventricles
• ECG: T waves


  Ventricular repolarisation (normally positive)
• How is blood formed?


  By Haemopoiesis, occurs in red bone marrow after birth (highly vascularised connective tissue).
• What is the function of red blood cells in the blood?

  Erythrocytes transfers oxygen and carbon dioxide. Has the role of transportation.
• What are components are there in the Blood Plasma?


  92% of water, 6% protein and 2% solutes. The function of water is to transport waste and regulate fluid levels.
• What other components are there in proteins?

  Albumin regulates, Fibrinogen protects, Antibodies protects too.
• What is the Buffy coat (<1%) made up of?


  Platelets and White blood cells (Leukocytes). There are 150 - 450,000 platelets and it serves as protection (bleeding in vessels). The cell fragments are there for when there is tissue injury, it activates swell in platelets. The white blood cells protect pathogens from getting into the body.
• What is Haemostasis?


  Blood clotting. It's a sequence of responses that stops bleeding.
• What is the first step of Haemostasis?


  Vascular Spasm occurs immediately after vessel damage (lasts mins-hrs). The Tunica Media (smooth muscle) causes Vasoconstriction to narrow the lumen of the vessels, reducing blood loss.
• What's is Platelet Plug Formation (Primary Haemostasis)?

  Hemostasis. Reversible process. Platelets adhere to exposed collagen fragments in the damaged vessel wall. Once platelets adhere they become activated and release chemical mediators to call additional platelets resulting aggregation and Platelet Plug Formation.
• What is Blood Clotting (Coagulation, Secondary Haemostasis)?


  It is an irreversible process. If blood is drawn from body it thickens and forms a gel. The gel eventually separates from liquid (serum). The serum is blood plasma minus the clotting proteins.
• What is the function of the heart valves?


  Blood passes through a valve before leaving each chamber of the heart. Valves present the backward flow of blood.
• Ventricles have thicker walls than atria because they have to do more work. Both atria act as receiving chambers for incoming blood and pump blood directly into ventricles.
• The inferior and superior vena cava drains oxygen poor blood into the right atrium. While the Pulmonary veins drain oxygen rich blood into the left atrium.
• Define Vasodilation


  The widening (increasing diameter) of blood vessels. The smooth muscles from arteries relax.
• Define Vasoconstriction


  Narrowing (decrease diameter, constriction) of blood vessels by small muscles in their walls.
• Constriction


  Making something (like an arteriole) smaller or more narrow
• Resistance


  The opposition to the flow of blood through blood vessels
• Arterioles


  Small blood vessels that are part of the circulatory system
• Blood pressure


  The force exerted by blood on the walls of blood vessels, measured in millimeters of mercury (mmHg)