Cohn Transcript Flashcards

What does "Integrated Human Anatomy and Physiology 1" refer to?

A first-semester course combining the study of human body structure (anatomy) and function (physiology) using an integrated, primarily systemic approach.

What is the one-word definition of anatomy?

Structure.

What aspects define "structure" in anatomy?

Size (volume, mass, density), shape, components, and spatial relationships to other structures.

Give a familiar example of structural analysis using a car.

A steering wheel has a specific size, shape, components (rubber and steel), and connections to other parts—analogous to anatomical structures.

How is a biceps muscle an example of anatomical structure?

It has size, shape, mass, specific components, and defined connections—typical anatomical descriptors.

What is gross anatomy?

The study of structures visible to the naked eye, typically through cadaver dissection.

Why is it called "gross" anatomy?

From the German word "gross" meaning large—refers to large-scale anatomy visible without magnification.

What are the two approaches to studying gross anatomy?

Systemic approach and regional approach.

What is the systemic approach in anatomy?

Studying the body system by system (e.g., nervous, skeletal), often used in integrated courses.

What is the regional approach in anatomy?

Studying body regions (e.g., chest, abdomen) and all systems within that region, used in med/vet schools.

Which systems are covered in this course (319)?

Integumentary, skeletal, muscular, nervous (incl. special senses).

What is the integumentary system?

The skin; largest organ, ~60% body weight, sole organ of this system.

How does the course approach anatomy and physiology?

With a systemic bias but some regionality, especially in labs (e.g., axial skeleton study).

What is histology?

Study of structure at the tissue level using a microscope; focuses on groups of identical cells.

What are tissues?

Groups of similar cells with a shared function and structure.

What are the four basic tissue types?

Epithelial, connective, muscle, nervous.

What defines epithelial tissue?

Covers/lines surfaces; includes skin and organ linings.

What defines connective tissue?

Supports, binds, or separates tissues/organs; most abundant and ubiquitous.

What defines muscle tissue?

Contractile cells that generate force; includes smooth, skeletal, and cardiac muscle.

What defines nervous tissue?

Includes neurons and glial cells; specialized for communication.

What is an example of identifying tissue subtypes?

Squamous epithelial tissue can be recognized by size, shape, staining, and spacing under a microscope.

What is cellular ultrastructure?

Fine structural detail of cells revealed with electron microscopes, e.g., nuclear pores, cristae in mitochondria.

Why was the electron microscope revolutionary?

Allowed visualization of structures up to a million times magnification—far beyond light microscopes.

What is physiology in one word?

Function.

How are anatomy and physiology related?

Structure supports and enables function; function is optimized by proper structure.

Why integrate anatomy and physiology in one course?

To appreciate their interdependence; better understanding through structure-function relationships.

What are some drawbacks of separating anatomy and physiology?

You may learn more detailed anatomy but lose the holistic structure-function integration.

What are the basic levels of biological organization?

Atoms → Molecules → Cells → Tissues → Organs → Organ systems → Organism.

What are the four most abundant elements in the human body?

Carbon, oxygen, hydrogen, nitrogen (COHN).

Why are COHN elements so abundant in the body?

They make up major macromolecules and water, which is ~60% of body weight.

What happens to body water content with age?

Decreases: ~80% at birth, ~60% in young adults, ~50% in older adults.

What macromolecules are built from COHN elements?

DNA, RNA, proteins, carbohydrates, and fats.

What is an atom?

The smallest unit of an element that retains the element’s properties (e.g., a carbon atom).

How is a cell defined?

A collection of molecules enclosed in a lipid membrane capable of carrying out life processes.

What tissue types do epithelial, nervous, and smooth muscle cells represent?

Epithelial = covering/lining, nervous = communication, smooth muscle = movement in hollow organs.

How are tissues organized into organs?

Multiple tissue types combine into macroscopic structures with unique functions.

What defines an organ?

A macroscopic structure made of at least two tissue types with a unique function.

What tissues make up the urinary bladder?

Smooth muscle, epithelial tissue, and connective tissue.

What is the function of the urinary bladder?

Holds and expels urine every 2–4 hours via muscular contractions.

Why is epithelial tissue important in hollow organs?

Lines inner surfaces, forming a barrier and interface with contents.

What roles does connective tissue play in organs like the bladder?

Provides structural support, tensile strength, and holds other tissues in place.

Why is smooth muscle essential in hollow organs?

Contracts to move or expel contents, e.g., urine in the bladder.

How does the bladder’s structure support its function?

Expandable, contractile, and tough—ideal for holding and expelling urine under pressure.

What is another name for the urinary system?

Excretory system.

What organs make up the urinary system?

Kidneys (2), ureters (2), urinary bladder, urethra.

What is the role of the kidneys?

Filter blood, create urine by removing wastes and excess ions/water.

What are ureters?

Smooth muscle-lined tubes transporting urine from kidneys to bladder.

What is the urethra?

Short tube carrying urine from bladder to the outside of the body.

How are organ systems interdependent?

If one organ or tissue fails, it can disable the whole system and eventually affect the entire body.

What is an example of system failure leading to fatality?

Kidney failure can be fatal without treatment.

What makes the brain an organ?

It's a macroscopic structure made of nervous and connective tissue with a unique function.

What cells make up nervous tissue besides neurons?

Glial cells (neuroglia).

What system is the brain part of?

The nervous system (along with spinal cord and peripheral nerves).

What is the stomach's role in the digestive system?

Stores food temporarily, begins digestion, passes contents to the small intestine.

Why is the stomach classified as a hollow organ?

It's expandable and lined with smooth muscle and epithelial tissue.

What tissues make up the stomach wall?

Epithelial, smooth muscle, and connective tissue—like the bladder.

What distinguishes one organ from another if both are hollow?

Their unique function: bladder stores urine; stomach stores/digests food.

What defines an organ system?

A group of anatomically/physiologically linked organs working for a shared function.

Why are systems considered mutually dependent?

Each system relies on others; failure in one affects overall function and health.

What is the final outcome of all systems working together properly?

A healthy, functioning human organism.

What is the overall concept linking anatomy and physiology?

Structure determines function; their integration is key to understanding biology.

What is homeostasis?

The maintenance of physiological variables within narrow limits despite internal or external environmental changes.

Why is homeostasis essential?

To prevent dysfunction or death due to deviation of physiological variables from optimal ranges.

What is a common example of a tightly regulated physiological variable?

Body temperature, normally ~98.6°F.

How does the body maintain 98.6°F in cold environments?

Through internal control mechanisms that resist temperature drops.

What happens when body temperature rises just 1–2°F?

You begin to feel unwell; fever symptoms occur around 100°F–102°F.

At what body temperature does death become likely?

Around 106°F if sustained.

What is the normal blood pH?

Approximately 7.4.

What pH range is incompatible with life?

Below 6.8 or above 7.8.

How does the body maintain stable blood glucose levels after consuming sugar?

Insulin is released to regulate glucose levels and maintain homeostasis.

What happens to blood glucose in healthy individuals during fasting?

It remains stable due to hormonal regulation (e.g., glucagon).

How are blood gases regulated during breath-holding?

Rising CO₂ and falling O₂ levels trigger brain responses that force breathing.

Why is voluntary breath-holding limited?

Brain centers force breathing due to rising CO₂ levels and loss of homeostasis.

What is another critical homeostatic variable besides temperature, pH, glucose, and gases?

Blood pressure.

What are electrolytes?

Ions dissolved in body fluids that play critical roles in physiological function.

What percentage of the body is water in young adults?

About 60%.

What is an ion?

An atom or molecule with more or fewer electrons than protons, resulting in a charge.

What is a cation?

A positively charged ion (fewer electrons than protons).

What is an anion?

A negatively charged ion (more electrons than protons).

What is a divalent cation?

A cation with a +2 charge (e.g., Ca²⁺).

What is a monovalent cation?

A cation with a +1 charge (e.g., Na⁺, K⁺).

What is a monovalent anion?

An anion with a -1 charge (e.g., Cl⁻).

What are examples of molecular ions?

Phosphate (PO₄³⁻) and bicarbonate (HCO₃⁻).

What is the hydronium ion and its notation?

H₃O⁺, often abbreviated as H⁺ in physiology.

Why is bicarbonate ion (HCO₃⁻) important?

It is a major blood buffer that helps resist pH changes.

What is the carbonic acid equilibrium reaction in blood?

H₂CO₃ ⇌ H⁺ + HCO₃⁻

What is a buffer?

A substance that helps resist changes in pH in a solution.

How are electrolyte concentrations maintained differently inside vs outside cells?

Some ions are homeostatically maintained at vastly different intra‑ vs extracellular levels.

What is the intracellular:extracellular ratio of potassium?

~35 times more concentrated inside cells.

What is the intracellular:extracellular ratio of sodium?

~15 times more concentrated outside cells.

What is the main mechanism for maintaining physiological variables?

Negative feedback.

Which two systems are responsible for most control functions?

Nervous system and endocrine system.

What is the primary function of the endocrine system?

Secretes hormones to regulate physiological processes.

What is a variable in homeostasis?

The physiological parameter being regulated (e.g., temperature).

What is the set point?

The target or ideal value for a homeostatic variable (e.g., 98.6°F for body temp).

What is the signal (stimulus) in negative feedback?

The difference between the current value and the set point.

Are signals considered positive or negative in this model?

Always positive; only the direction (up/down) is tracked.

What is the ideal signal value?

Zero—indicating the variable equals the set point.

What is the correction mechanism in negative feedback?

A response that pushes the variable in the opposite direction of deviation to return to set point.

Why is it called "negative" feedback?

Because the system counteracts the direction of the deviation.