Circulatory and Respiratory Systems Flashcards
What do insects have in place of blood?
Hemolymph, which bathes their organs rather than traveling in blood vessels.
Plasma
Liquid portion of blood, mostly water, but containing dissolved glucose, hormones, and proteins, 50% of blood.
Red blood cells
- Make up the majority of blood cells, 45% of blood
2. Shaped like disks and filled with hemoglobin, allowing them to transport oxygen.
Hemoglobin
Protein that is made partly of iron and used to transport oxygen. Need sufficient iron to get enough oxygen, or anemia results.
White blood cells
- Fight disease, 5% of blood
2. Phagocytes and lymphocytes (B and T cells).
Phagocytes
Eat pathogens and dead or sick cells.
B cells
Make antibodies
Antibodies
Markers that bind to foreign things and mark them for destruction.
T cells
- Helper T cells help B cells and other T cells to divide and proliferate.
- Killer T cells kill any cell infected by a virus to stop them from reproducing.
How does HIV work?
Infects helper T cells, killing them. T cells help B and T cells to reproduce, so they aren’t able to fight infections and many infections result.
Platelets
- Help blood to clot
2. Help to convert protein fibrinogen into threads (fibrin)
Where are all blood cells made?
The bone marrow
What determines blood type?
Blood type is genetic and determined by membrane proteins that sit on surface of white blood cells. Type Ia is type A protein, Ib is type B protein, ii is no protein.
What happens during blood transfusions if a person’s body doesn’t recognize the blood type?
The new red blood cells will clump up (agglutination) and be destroyed.
Which blood type is the universal recipient?
Type AB- it recognizes type A and type B proteins, and type O has no proteins.
Which blood type is the universal donor?
Type O- it can only receive type O, but anyone can receive it because it has no proteins.
Arteries
- Carry blood away from the heart
- Thick, muscular walls that regulate diameter to regulate blood flow
- High blood pressure due to push from heart
- Branch into arterioles, then capillaries
Capillaries
- Smallest blood volume
- Site of gas exchange between blood and tissues
- Very low blood flow and blood pressure
- Merge into venules, which merge into veins
Veins
- Carry blood to the heart
- Low blood pressure, so skeletal muscles contract to squeeze blood
- Don’t regulate blood flow
- Valves ensure that blood only moves in one direction.
Aorta
Large artery moving blood away from the heart
Vena Cava
Large vein moving blood toward the heart.
How does fluid move into tissues?
Arteries force fluid into tissues, which is mostly lost as not all of it returns to veins.
Lymphatic System
Network of vessels that begins at tissues and ends at veins. Recaptures extra fluid, filters it, and returns it to th blood.
Lymph nodes
Concentrated areas of white blood cells that filters fluid and can destroy anything harmful.
Lymphatic vessels
Similar to veins, with low pressure, valves, and skeletal muscle squeezes fluid (lymph).
Edema
Swelling due to trapped tissue fluid. Remaining in one position can limit muscle contraction and therefore restrict flow of fluid.
Chambers of the heart
- Right atria, right ventricle, left atria, left ventricle
- The right side pumps blood through pulmonary circuit, left through systemic circuit
- Blood enters through atria
Blood pathway through the heart
- Pulmonary circuit takes oxygen poor blood returning from the tissues and pumps it into the lungs.
- Oxygen poor blood enters at the right atrium through the superior and inferior vena cava, going from right atrium to the right ventricle.
- Goes from right ventricle through pulmonary artery to the lungs.
- At the lungs, gas exchange occurs.
- Blood returns to the left atrium through the pulmonary veins and goes to the left ventricle
- Leaves the heart through the aorta to bring blood to the rest of the body.
Atrioventricular valves
The valves between the atria and ventricles. These valves close first. Tricuspid and bicuspid/mitral.
Semilunar valves
Between the ventricles and the arteries. Pulmonary and aortic.
Systole
When the heart contracts.
Diastole
When the heart relaxes.
The Conduction Zone
- Parts of the respiratory system designed for ventilation only.
- Nose, pharynx, larynx, trachea, bronchi, bronchioles
Nose
Air is warmed, filtered, and humidified.
Trachea
- Branches into bronchi and bronchioles
2. Trachea and bronchial tubes are lined with cells with cilia that secrete mucus to trap dirt and move it upward.
Alveoli
Thin walled bubbles of tissue contained in small bronchioles.
How does gas exchange occur?
- Alveoli clusters are surrounded by capillaries, allowing for gas exchange.
- Occurs by passive diffusion, as both gases are lipid soluble and move down concentration gradient.
- Carbon dioxide and water are waste products of respiration and are released when we exhale.
What is the range for blood pH?
7.35-7.45. Must remain constant.
What does too much carbon dioxide do to blood?
Makes the blood acidic. CO2 is hydrophobic and can’t dissolve in plasma, so it’s converted to carbonic acid and bicarbonate, which are hydrophilic.
What happens if the blood gets too acidic?
Respiratory rate speeds up to get rid of the extra carbon dioxide. If the body is too alkaline, rate will decrease. Medulla oblongata adjusts respiratory rate based on CO2 levels.
Inspiration
Chest cavity increases in volume, decreasing air pressure, letting air go into lungs.
Expiration
Diaphragm relaxes, reducing volume and forcing air out.
How do we breathe?
- Muscles in the chest wall expand and contract the lungs.
- The diaphragm curves under the lungs when relaxed and flattens out when it contracts, increasing the size of the chest cavity.
- For forced expiration, abdominal muscles contract.
