Ch: 21 Circulation Flashcards
What is the difference between an open and closed circulatory system?
Open circulatory systems contain hemolymph or “interstitial fluid”
Closed circulatory systems contain blood
What organisms contain an open circulatory system?
Arthropods and mollusks
What organisms contain an closed circulatory system?
Annelids and vertebrates
What are the most successful organisms in the world?
Arthropods
Arteries carry blood __To/Away__ from the heart.
Arteries carry blood away from the heart
What blood vessels contain the highest amount of resistance?
Arterioles
What blood vessels is the speed of blood the slowest?
Capillaries
makes sense bc thats where the most O2 and nutrients are exchanged
What blood vessels contain the LARGEST cross-sectional area?
Capillaries
more surface area = more nutrient exchange
Capillaries converge into what is called a ______… which merge to form veins.
Venule
Which of the following blood vessels is THICKER, contains MORE smooth muscle, and is more elastic?
A. Arteries
B. Veins
A. Arteries
Arteries have thicker walls and are more elastic than veins bc of blood pressure
Which of the following blood vessels contains valves?
A. Arteries
B. Veins
B. Veins
Valves in the veins prevent backward flow of blood, while pressure from muscle contractions helps to move the blood through veins TOWARD the heart
Which of the following blood vessels has the lowest blood pressure?
A. Arteries
B. Veins
B. Veins
How many heart chambers are in the following organisms?
- Fish
- Reptiles and amphibians
- Mammals and birds
Fish = 2 chambered hearts (two-hearted ale)
Reptiles and amphibians contain 3 chambered hearts EXCEPT crocodiles and alligators (4 chambered)
Mammals and birds = 4 chambered hearts
“A MUST KNOW FOR THE DAT”
Discuss each of the following terms:
- Atria
- Ventricle
Atria = upper chamber
Ventricle = lower chamber
Discuss each of the following terms:
- Superior Vena Cava
- Inferior Vena Cava
Superior vena cava: brings blood low in O2 to right atria from UPPER body
Inferior vena cava: brings blood low in O2 to the right atria from the LOWER body
Discuss each of the following terms:
- Tricuspid valve
- Mitral Valve (bicuspid)
Tricuspid valve: between left atria and right ventricle
Bicuspid valve (mitral): between left atria and left ventricle
What is the Lub-Dup sounds of the heart indicate?
Lub: 1st sound; AV valves close
Dup: 2nd sound; Semilunar valves close
What is the difference between systolic pressure and diastolic pressure?
Systolic = ventricles contract
Diastolic = ventricles relax
***What type of muscle is the cardiac muscle?
***Mononucleated, striated, loads of mitochondria
Which of the following is the pacemaker?
A. SA node
B. AV node
A. SA node
found in right atrium
What is the pathway of the heart’s electrical system?
SA node –> AV node –> Bundle of His and Purkinje fibers
The ventricles contract when impulses reach the His bundles and Purkinje fibers
What are the steps of blood flow through the heart?
- Superior Vena Cava –> Right atrium
- Right atrium –> Tricuspid valve
- Tricuspid valve –> right ventricle
- Right ventricle –> pulmonary artery –> out of heart
- Pulmonary Vein –> left atrium –> Mitral (bicuspid)
- -> left ventricle –> aortic valve –> Aorta –> out of heart
What is the largest artery in the body?
Aorta
Let us trace a drop of blood in the heart circuit:
What are the 5 steps
- Blood from the upper and lower body is low in O2.. high in CO2, is brought to the Right Atria via the Superior and Inferior Vena Cava
- Right Atria to the Right Ventricle through the Tricuspid valve
- From the Right Ventricle, blood is propelled to the Right and Left Pulmonary Arteries, which are low in O2, and taken to the lungs
- Blood is oxygenated within the lung capillaries and transported to the Left Atrium, via the Pulmonary Veins
- Blood now goes from the Left Atrium to the Left Ventricle. Oxygenated blood now leaves the left ventricle thought the Ascending Aorta
***In the lungs O2 and CO2 are exchanged in tiny sacs called _______.
Alveoli
***What is the functional unit of the respiratory system?
Alveoli
***Gas exchange in the lungs via alveoli occurs by _________ diffusion.
Passive
Which of the following blood vessels is high in O2?
A. Pulmonary Artery
B. Pulmonary Vein
B. Pulmonary Vein
(Usually arteries are high in O2… but it is the opposite when it comes to the Pulmonary arteries and veins)
“FOR THE DAT”
The RIGHT side of the heart carries _______ blood.
Deoxygenated
RIGHT = deoxygenated blood
LEFT = Oxygenated blood
