Human Physiology Exam Module 1: Chapter 1-5

Where does glycolysis take place?

Cytosol

What is the study of the functions of organisms?

Physiology

What is homeostasis?

Maintenance of relatively constant conditions within the body's internal environment.

What does a homeostatic control mechanism do?

The Control Center receives and processes information from receptors about changes in a variable and compares it to the set point.

What type of feedback is commonly used in homeostatic systems?

Negative feedback.

What is the set point?

The normal or desired value of the regulated variable in a homeostatic system.

What are effectors?

Cells, tissues, or organs that respond to neural or chemical signals.

What are the four major cell types?

Neurons, muscle cells, epithelial cells, and connective tissue cells.

What does ICF stand for?

Intracellular Fluid.

What does ECF stand for?

Extracellular Fluid.

What is the function of epithelial cells?

Regulate exchange and found in skin and linings of hollow organs.

What is the role of neurons?

Communicate via electrical and chemical signals.

What is the function of connective tissue?

Provide support for other structures and link them together.

What is the primary function of total body water?

Represents the total volume of water in all compartments of the body.

What does extracellular fluid include?

Fluid found outside the blood called interstitial fluid.

What are the sensors in a homeostatic regulatory mechanism?

Cells or organs that detect changes in the internal environment.

What are the basic cellular functions?

Provide structural support, facilitate growth, enable energy production, and allow transport.

What is the significance of negative feedback in homeostasis?

Response goes in the opposite direction to restore the normal state.

What is positive feedback?

Response goes in the same direction as the change.

What is the role of the integrating center?

Processes sensory information and communicates commands to effectors.

What is a common example of positive feedback?

Aldosterone stimulates the reabsorption of sodium ions.

Where does the linking step of cellular respiration occur?

In the mitochondrial matrix.

What are the stages of cellular respiration?

Glycolysis, Krebs cycle, Oxidative phosphorylation.

What is passive transport?

Movement of molecules down a concentration gradient without energy.

What is active transport?

Movement of molecules up a concentration gradient requiring energy.

What is the process of osmosis?

Specific passive transport of water across a membrane.

What is facilitated diffusion?

Transport proteins assist larger or polar molecules across the membrane.

What are aquaporins?

Water channels facilitating the passage of water across cell membranes.

What distinguishes primary active transport from secondary active transport?

Primary uses ATP directly; secondary utilizes the gradient created by primary.

What is glycolysis?

The breakdown of glucose into pyruvic acid in the cytoplasm.

What is the final product of glycolysis?

2 Pyruvate molecules.

How many ATP are produced in glycolysis?

2 ATP.

Where is glycogen primarily stored in the body?

In muscle and liver cells.

What is the function of mitochondria?

Generate ATP through cellular respiration.

What is the structure of ATP?

A nitrogenous base (adenine), ribose sugar, and three phosphate groups.

What is glycolysis often referred to as?

The splitting of sugar.

What is lipolysis?

The breakdown of triglycerides for energy.

What do NADH and FADH2 do?

Transfer electrons in cellular respiration.

What are desmosomes?

Junctions that hold adjacent cells together.

What are gap junctions?

Membrane channels connecting two cells.

What are tight junctions?

Cell junctions preventing leakage between cells.

What is the basic structure of an extracellular matrix?

Molecules and proteins that provide support and communication between cells.

What influences passive transport rates?

Magnitude of driving force, membrane surface area, and permeability.

What influences active transport?

Concentration of pumps/channels and individual pump/channel rates.

What is the primary difference between endocytosis and exocytosis?

Endocytosis brings substances into the cell, while exocytosis expels them.

What distinguishes paracrines from hormones?

Paracrines act locally, while hormones are released into the bloodstream.

What defines lipophilic vs hydrophilic chemical messengers?

Lipophilic messengers pass through membranes easily; hydrophilic require receptors.

What role do integral membrane proteins play?

They span the lipid bilayer and may function as channels.

What is chemiosmotic coupling?

The process that couples electron transport to ATP synthesis.

What does the Golgi apparatus do?

Modifies, sorts, and packages proteins and lipids for transport.

What is the function of lysosomes?

Break down waste materials and cellular debris.

What does oxidative phosphorylation produce?

ATP through electron transport and chemiosmosis.

How many NADH are produced during glycolysis?

2 NADH.

What is the main purpose of enzymes?

Catalyze biochemical reactions.

What is phosphorylation?

The addition of a phosphate group to a molecule.

What is an example of a glycolytic enzyme?

Hexokinase.

What happens during the Krebs cycle?

Acetyl CoA is broken down producing NADH and FADH2.

What is the final electron acceptor in the electron transport chain?

Oxygen.

What happens during phagocytosis?

The engulfing of large particles by the cell.

What is receptor-mediated endocytosis?

A specific form of endocytosis that involves receptors.

What are eicosanoids?

Modified fatty acids that act as signaling molecules.

What characterizes lipophilic receptors?

Located in the cytoplasm or nucleus of target cells.

What is the role of calcium in signal transduction?

Acts as a second messenger in various signaling pathways.

What are the differences in neurotransmitter and hormone signaling?

Neurotransmitters act quickly; hormones have longer-lasting effects.

What is the role of cell receptors?

Bind chemical messengers to initiate cellular responses.

What describes a ligand-gated channel?

Opens in response to binding of a ligand.

What is the purpose of sodium-potassium pumps?

Maintain membrane potential by moving ions against their gradient.

What is mechano-sensitivity in cell communication?

Cells respond to mechanical stimuli.

What is the primary function of ribosomes?

Site of protein synthesis.

What is the plasma membrane?

The barrier separating a cell's interior from its environment.

What is the function of smooth endoplasmic reticulum?

Lipid synthesis and detoxification processes.

What happens during dehydration synthesis?

Two molecules are joined together releasing a water molecule.

What are three classes of chemical messengers?

Amines, peptides, and steroids.

What defines secondary active transport?

Utilizes the energy from an ion gradient established by primary active transport.

What is the distinguishing function of neurotransmitters?

Transmit signals across synapses in the nervous system.

What is calmodulin?

A calcium-binding messenger protein.

What is creatine phosphate's role in muscle energy?

Quickly regenerates ATP during high-intensity exercise.

How does temperature affect membrane permeability?

Higher temperature increases fluidity, enhancing permeability.

What is ATP synthase?

Enzyme that produces ATP during oxidative phosphorylation.

What characterizes the function of peptide hormones?

Bind to receptors on the plasma membrane of target cells.

What is the significance of the cytoskeleton?

Provides structural support and facilitates movement within cells.

What process occurs in the rough endoplasmic reticulum?

Protein synthesis and folding.

What is signal transduction?

The process by which a cell responds to signals received.