Biology Exam - Anatomy

Key Definitions:

• Amino acids: The building blocks of proteins.

• Aorta: The largest artery in the body, carrying oxygenated blood from the left ventricle to the rest of the body.

• Arteries: Blood vessels that carry blood away from the heart.

• Atria: The two upper chambers of the heart that receive blood.

• Atrioventricular node (AV node): A part of the heart's electrical conduction system that delays the electrical signal from the atria to the ventricles.

• Atrioventricular valves: Valves located between the atria and ventricles that prevent backflow of blood.

• Capillaries: Tiny blood vessels that connect arteries and veins, where exchange of nutrients and gases occurs.

• Diastole: The phase of the cardiac cycle when the heart muscle relaxes and the chambers fill with blood.

• Digestive organs & accessory organs: Organs involved in digestion, including the mouth, esophagus, stomach, intestines, liver, pancreas, and gallbladder.

• Fatty acids: The building blocks of lipids (fats).

• Monosaccharides: Simple sugars that are the building blocks of carbohydrates.

• Myocardium: The muscular tissue of the heart.

• Myogenic muscle: Muscle tissue that generates its own contractions (e.g., the heart muscle).

• Oxygenated and deoxygenated blood: Blood that is rich in oxygen (oxygenated) and blood that has had much of its oxygen removed (deoxygenated).

• Pulmonary artery: The artery that carries deoxygenated blood from the right ventricle to the lungs.

• Pulmonary vein: The vein that carries oxygenated blood from the lungs to the left atrium.

• Purkinje fibres: Specialized muscle fibers that conduct electrical impulses through the ventricles, causing them to contract.

• Respiratory organs: Organs involved in gas exchange, including the lungs, trachea, and bronchi.

• Semilunar valves: Valves located at the exits of the ventricles (aortic and pulmonary valves) that prevent backflow of blood.

• Septum: A wall that divides the heart into left and right sides.

• Sinoatrial node (SA node): The heart's natural pacemaker, which generates electrical impulses that initiate heartbeats.

• Systole: The phase of the cardiac cycle when the heart muscle contracts and pumps blood out of the chambers.

• Veins: Blood vessels that carry blood towards the heart.

• Vena cava: The large vein that carries deoxygenated blood from the body to the right atrium.

Ventricles: The two lower chambers of the heart that pump blood out to the lungs or the rest of the body.

Key concepts:

• Digestive System:

  • Macronutrients: Carbohydrates, proteins, fats.

  • Micronutrients: Vitamins, minerals.

  • Organs/Parts: Mouth, esophagus, stomach, small intestine, large intestine, rectum, anus.

  • Accessory Organs: Salivary glands, liver, gallbladder, pancreas.  

  • Enzymes: Biological catalysts that speed up digestion (e.g., amylase, pepsin, lipase).

  • Mechanical Digestion: Physical breakdown of food (e.g., chewing, churning).

  • Chemical Digestion: Breakdown of food by enzymes.

  • Digestion in:

    • Mouth: Salivary amylase breaks down carbohydrates.

    • Stomach: Pepsin breaks down proteins.

    • Small Intestine: Most digestion and absorption occur here with the help of enzymes from the pancreas and bile from the liver.

  • Absorption: Nutrients absorbed in the small intestine, water and some vitamins in the large intestine.

  • Blood Sugar Regulation: Insulin and glucagon regulate blood glucose levels. Diabetes is a disorder of blood sugar regulation.

• Respiratory System:

  • Organs/Parts: Nose, pharynx, larynx, trachea, bronchi, lungs, alveoli.

  • Mechanics of Respiration:

    • Inhalation: Diaphragm contracts, chest cavity expands, air rushes in.

    • Exhalation: Diaphragm relaxes, chest cavity contracts, air is pushed out.

  • Respiratory Disorders: COPD, asthma, bronchitis, etc.

• Circulatory System:

  • Components of Blood: Plasma (liquid part), red blood cells (carry oxygen), white blood cells (immune function), platelets (clotting).

  • Blood Cells:

    • Red Blood Cells: Erythrocytes, carry oxygen using hemoglobin.

    • White Blood Cells: Leukocytes, involved in immune responses.

    • Platelets: Thrombocytes, involved in blood clotting.

  • Clotting: A complex process involving platelets and clotting factors.

  • Blood Types: A, B, AB, O. Determined by antigens on red blood cells.

  • Blood Vessels:

    • Arteries: Carry blood away from the heart.

    • Capillaries: Site of exchange between blood and tissues.

    • Veins: Carry blood toward the heart.

• Heart Structure and Function: Four chambers (two atria, two ventricles), valves (prevent backflow).

• Blood Flow: Deoxygenated blood enters the right atrium, goes to the right ventricle, to the lungs (pulmonary circulation), oxygenated blood returns to the left atrium, goes to the left ventricle, and then to the body (systemic circulation).

• Heart Conduction System: SA node (pacemaker) → AV node → Bundle of His → Purkinje fibers.

• Circulations:

  • Systemic Circulation: Blood flow between the heart and the body.

  • Cardiac Circulation: Blood flow within the heart muscle itself.

  • Pulmonary Circulation: Blood flow between the heart and the lungs.

• Blood Pressure: Force of blood against artery walls. Hypertension (high blood pressure). Substances move into and out of capillaries through diffusion, osmosis, and filtration.

• Cardiovascular Disorders: Heart attacks, strokes, atherosclerosis, etc.