Ch. 17 - Cardiovascular Physiology I: The HeartWorksheetSee all chapters
All Chapters
Ch. 1 - Introduction to Physiology
Ch. 2 - Molecules and Molecular Interactions
Ch. 3 - Cells and Tissues
Ch. 4 - Cell Metabolism: Bioenergetics, Enzymes, and Respiration
Ch. 5 - Membrane Dynamics
Ch. 6 - Cell Communication
Ch. 7 - Integumentary System
Ch. 8 - Bone and Cartilage
Ch. 9 - Skeletal System
Ch. 10 - Joints
Ch. 11 - Muscles
Ch. 12 - The Nervous System I: Neurons and Neuronal Networks
Ch. 13 - The Nervous System II: The Central Nervous System
Ch. 14 - The Autonomic Nervous System
Ch. 15 - Sensory Physiology
Ch. 16 - The Endocrine System
Ch. 17 - Cardiovascular Physiology I: The Heart
Ch. 18 - Cardiovascular Physiology II: Blood, Blood Vessels, Circulation, and Exchange
Ch. 19 - The Urinary System
Ch. 20 - Respiratory Physiology
Ch. 21 - Acid-Base Balance-- Controlling Blood pH
Ch. 22 - Introduction to the Immune System
Ch. 23 The Lymphatic System
Ch. 23 - The Digestive System
Ch. 24 - Regulation of Metabolism and Energy Balance
Ch. 25 - Human Sexual Reproduction and Development

Concept #2: Nodal Fiber APs, Funny Channels, Automaticity

Practice: Epinephrine is a hormone (and drug) that binds to β1 adrenergic receptors on nodal fibers. Binding of epinephrine to β1 adrenergic receptors activates an intracellular signaling cascade that increases the conductance of funny channels. Which of the following phases of the nodal fiber action potential is likely to be directly affected by epinephrine?

Practice: Epinephrine is a hormone (and drug) that binds to β1 adrenergic receptors on nodal fibers. Binding of epinephrine to β1 adrenergic receptors activates an intracellular signaling cascade that increases the conductance of funny channels. Which of the following is the likely effect of epinephrine on heart rate?