1.2.5 The cardiac cycle and pathway of blood

• The cardiac cycle involves both contraction and relaxation of the heart muscles.

  True
• Systole is the contraction phase of the heart muscles.


  True
• During atrial systole, blood is pushed from the atria into the ventricles.

  True
• The cardiac cycle involves the contraction and relaxation of both the atria and ventricles
• During systole, blood flows into the pulmonary artery and the aorta
• The tricuspid valve is located between the right atrium and right ventricle.


  True
• Heart valves ensure blood flows in one direction through the heart chambers.

  True
• Match each heart valve with its location:

  Tricuspid ↔️ Right atrium and right ventricle

  Mitral ↔️ Left atrium and left ventricle

  Aortic ↔️ Left ventricle and aorta

  Pulmonary ↔️ Right ventricle and pulmonary artery
• The aortic valve prevents backflow from the aorta into the left ventricle.
• Trace the pathway of blood through the heart:

  1️⃣ Blood enters the right atrium

  2️⃣ Blood passes through the tricuspid valve into the right ventricle

  3️⃣ Blood is pumped through the pulmonary valve into the pulmonary artery

  4️⃣ Blood flows to the lungs, picks up oxygen, and returns to the left atrium

  5️⃣ Blood passes through the mitral valve into the left ventricle

  6️⃣ Blood is pumped through the aortic valve into the aorta

  7️⃣ Blood is distributed to the body's capillaries
• Deoxygenated blood from the body first enters the left atrium.

  False
• Match each phase of the cardiac cycle with its description:

  Atrial Systole ↔️ Atria contract, pushing blood into ventricles

  Ventricular Systole ↔️ Ventricles contract, pumping blood into pulmonary artery and aorta

  Atrial Diastole ↔️ Atria relax and fill with blood from veins

  Ventricular Diastole ↔️ Ventricles relax and fill with blood from atria
• Order the phases of the cardiac cycle during systole:

  1️⃣ Atrial Systole

  2️⃣ Ventricular Systole
• The aortic and pulmonary valves open during diastole.

  False
• Heart valves ensure blood flows in one direction through the heart chambers.


  True
• During systole, the aortic and pulmonary valves open to allow blood to flow into the aorta and pulmonary artery
• The mitral valve prevents backflow from the left ventricle to the left atrium.


  True
• Blood enters the right atrium from the veins carrying deoxygenated blood
• What is the function of the right atrium?

  Receives deoxygenated blood
• Arteries have thick, muscular walls to withstand high blood pressure.


  True
• What is the primary function of capillaries in the circulatory system?

  Facilitate gas and nutrient exchange
• The cardiac cycle is the complete sequence of events in one heartbeat
• The two main phases of the cardiac cycle are systole and diastole
• Diastole is the relaxation phase of the heart muscles.
• The cardiac cycle consists of two main phases: systole and diastole
• Systole refers to the contraction of heart muscles.


  True
• Match each heart valve with its function:

  Tricuspid ↔️ Prevents backflow from right ventricle to right atrium

  Mitral (Bicuspid) ↔️ Prevents backflow from left ventricle to left atrium

  Aortic ↔️ Prevents backflow from aorta to left ventricle

  Pulmonary ↔️ Prevents backflow from pulmonary artery to right ventricle
• What are heart valves made of?

  Flap-like structures
• During diastole, the tricuspid and mitral valves allow blood to flow from the atria into the ventricles
• What is the function of the tricuspid valve?

  Prevents backflow from right ventricle
• Heart valves open during systole to allow blood to flow through the heart.


  True
• What blood vessels carry oxygenated blood from the lungs to the left atrium?

  Pulmonary veins
• The cardiac cycle consists of two main phases: systole and diastole
• What happens during atrial systole?

  Blood is pushed into ventricles
• During diastole, the ventricles relax and fill with blood from the atria
• Which valves open during diastole to allow blood flow from the atria to the ventricles?

  Tricuspid and mitral
• Where is the tricuspid valve located in the heart?

  Between right atrium and right ventricle
• Which valve prevents backflow from the aorta into the left ventricle?

  Aortic valve
• Steps in the pathway of blood through the heart

  1️⃣ Blood enters the right atrium from veins

  2️⃣ Blood passes through the tricuspid valve into the right ventricle

  3️⃣ The right ventricle pumps blood through the pulmonary valve into the pulmonary artery

  4️⃣ In the lungs, blood picks up oxygen and returns to the left atrium via the pulmonary veins

  5️⃣ Blood passes through the mitral valve into the left ventricle

  6️⃣ The left ventricle pumps oxygenated blood through the aortic valve into the aorta
• Which valve does blood pass through when moving from the right ventricle to the lungs?

  Pulmonary valve