Organ Systems Flashcards
Describe the blood flow in circulatory system
Double Circulation
- Blood drains from superior vena cava (from head and arms) or inferior vena cava (from lower trunk and legs) into the right atrium
- Right ventricle pumps deoxygenated blood out to the lungs via pulmonary artery
- Returns from the lungs to the left atrium through pulmonary vein
- Leaves heart through the aorta
Are arteries and veins oxygen-rich or oxygen poor?
What is the only vein and artery that is opposite of the other veins and arteries?
Also describe where they go
Artery- Oxygen rich away from heart
Vein- Oxygen poor blood back to heart
Pulmonary Artery- Oxygen poor blood to lungs from heart
Pulmonary Vein- Oxygen rich blood from lungs to heart
Describe the Two Parts of the Cardiac Cycle
Diastole- Heart is relaxed, blood flow from vein to heart chamber
* Blood pressure decrease
Systole- Heart muscle contracts, blood flow from atrium to ventricles and is pumped into arteries
* Blood pressure increase
Which blood vessel has the highest or lowest blood pressure?
Which blood vessel has the fastest slowest velocity?
Order blood vessel from thickest to thinnest walls
Arteries
- Have elastic fibers that recoil after stretching
- Thickest walls, highest blood pressure and velocity
Veins
- Have thinner walls compared to arteries
- Lower blood pressure and velocity
- One way valves permit blood to flow only toward heart
Capillaries
- Thin walls
- Exchange gas and fluid with interstitial fluid
- Also exchanges materials between blood and tissue cells
Blood pressure
- Depends on cardiac output and resistance of vessels
- Pressure is highest in arteries
- Blood velocity is slowest in capillaries
Hypertension
Cardiac output
Heart rate
Heart valves
Hypertension (high blood pressure) is a serious cardiovascular problem that in most cases can be controlled
Cardiac output: volume of blood that each ventricle pumps per minute (heart rate x stroke volume)
Heart rate is the number of heart beats per minute
Heart valves prevent backflow of blood
Sinoatrial and Atrioventricular nodes
Sinoatrial node “natural pacemaker”
→ Generates electrical impulses in atria and sets rate of heart contractions
Atrioventricular node
→ Relays signals to ventricles and trigger ventricular contractions
What do electrocardiograms do?
Detects electrical impulses in heart
Can provide data about heart health
Heart Diseases
Cardiovascular disease
Heart attack
Stroke
Atherosclerosis
Cardiovascular disease- Disorders of the heart and blood vessels
Heart attack
-Damage or death of cardiac muscle tissue
-Usually results from blocked coronary artery
Stroke
-Death of brain tissue due to lack of O2
-Results from rupture or blockage of arteries in the head
Atherosclerosis
-Fatty deposits called plaques develop in inner wall of arteries
-Narrows the passages which blood can flow
Blood cell types
Plasma
Leukocytes
Erythrocytes
Platelet
Plasma
-Contain various inorganic ions, proteins, nutrients, wastes, gases, and hormones
Red blood cells (erythrocytes)
-Transports O2 bound to hemoglobin
White blood cells (leukocytes)
-Fight infections
-Some are phagocytes which engulf and digest bacteria
Platelets
-Cell fragments that are involved in blood clotting
Anemia
Leukemia
What hormone stimulates RBC production?
Anemia- A condition in which the blood doesn’t have enough healthy red blood cells
- Caused by low amounts of hemoglobin or low number of red blood cells
- Causes fatigue due to lack of oxygen in tissues
Leukemia- cancer of leukocytes
The hormone erythropoietin (EPO) stimulates bone marrow to produce more red blood cells
What blood cell type clots blood?
Describe the process
Blood contains self-healing materials that activate when blood vessels are injured
Platelets adhere to connective tissue in damaged vessels and help convert fibrinogen to fibrin, forming a clot to plug the leak
What happens when a stem cell divides?
One daughter cell remains a stem cell
The other one can take a specialized function
Immunity Types
Active
Passive
Natural
Artificial
Active- Body is creating agent that is going to fight the disease
Passive- Body is not actively creating agent to fight disease
Natural- Created by body without medical intervention
Artificial- There is medical intervention involved
Define
Pathogens
Antigen
Antibody
Pathogens: agents that cause disease
Antigen: Any molecule that elicits an adaptive immune response
Antibody: Immune protein that attaches to antigen to counter its effects
Innate and Adaptive Immunity
Describe Herd Immunity
Innate immunity
○ Immunity that is there all the time
○ Innate means inborn
○ Non-specific
Adaptive Immunity
○ Acquired immunity
○ Activated after exposure to specific pathogens
○ Triggered by infections and vaccines
Herd immunity- When most people in a population are vaccinated, a disease cannot spread
Steps of immune response
- Innate external barrier (ex. Skin or acidic environment)
* If external barriers are breached*
| - Innate internal defenses (ex. Inflammatory response, killer cells, phagocytic cells)
If innate responses don’t clear infection
| - Adaptive responses (ex. Lymphocytes)
○ Defense against pathogens in fluids (humoral)
○ Defense against pathogens inside body cells (cell-mediated)
Lympathic System
Lymphatic vessels
Lymph nodes
Lymph
Lymphatic vessels: Vessels which collect fluid from body tissue and return it as lymph to blood
Lymph nodes: little round organs packaged with macrophages and lymphocytes
Lymph: similar to interstitial fluid that surrounds body cells but contain less oxygen and fewer nutrients
Interstitial Fluid
Interstitial fluid is the fluid that bathes body cells and is constantly renewed by the blood.
Two main functions of lympathic system
- Return tissue fluid back to circulatory system
- To fight infection
Two main lymphatic ducts
Right lymphatic duct
Thoracic Duct
Right lymphatic duct- Drains right side of body
Thoracic Duct- Drains left side of body
Lymphocyte and the two main types
B Lymphocyte
T Lymphocyte
Lymphocyte- Type of white blood cell part of immune system that originates from stem cells in bone marrow
- B Lymphocyte or B Cells: Involved with humoral immune response (action against free-floating antigens in body fluids)
- Produces antibodies to bind on antigen - T Lymphocytes or T cells: Involved with cell-mediated immune response (action against infected cells)
- Wipes out infected or cancerous cells
Both the humoral and cell-mediated immune responses are initiated when lymphocytes recognize antigens
Epitope
Antigen-binding site
Epitope: Site on antigen that antibodies and antigen receptors bind to
Antigen-binding site: Specific region on antigen receptor on antibody that recognizes an epitope
Clonal selection
Clonal selection
-The humoral and cell-mediated immune responses defend against a wide variety of antigens through a process known as clonal selection
-When an antigen enters the body, it activates only a subset of lymphocytes that have receptors specific for the antigen
-The selected cells multiply into clones of short-lived effector cells(plasma cells) specialized for defending against that antigen and into memory cells, which confer long-term immunity
What do antibodies do specifcally?
-Antibodies mark a pathogen by combining with it to form an antigen-antibody complex
-Antibodies have antigen-binding sites that bind to specific antigens
-Antibodies assist innate responses in eliminating the invader
Autoimmune disorders
Immunodeficiency disorders
Autoimmune disorders- the immune system target self-molecules
Immunodeficiency disorders- immune components are lacking and frequent infections occur