Human Body Orientation and Chemical Organization Flashcards

Vocabulary study cards covering introductory human anatomy, homeostasis, body cavities, chemical fundamentals, and biological macromolecules based on the lecture material.

Physiology

The discipline that specifically studies how body structures function.

Histology

The microscopic study of tissues and cellular structures.

Structural Levels of Organization

The sequence of structural complexity in the body: Chemical $\rightarrow$ Cellular $\rightarrow$ Tissue $\rightarrow$ Organ $\rightarrow$ Organ System $\rightarrow$ Organismal.

Major Tissue Types

The four major types of tissue in the human body: epithelial, connective, muscular, and nervous.

Metabolism

The sum of all chemical processes that allow the body to use energy.

Skeletal System

The organ system that serves as the body's framework and provides structural support.

Endocrine System

The organ system that produces chemical messengers called hormones to regulate body processes.

Homeostasis

The body's ability to maintain relatively stable internal conditions around a set point.

Negative Feedback Mechanism

A homeostatic control mechanism that maintains stability by reversing the direction of the initial change.

Negative Feedback Loop Components

The three essential components required for negative feedback: Sensor/Receptor, Control Center, and Effector.

Positive Feedback Loop

A physiological control mechanism that amplifies the original stimulus, such as during labor and childbirth.

Anatomical Position

The standard body reference position where the palms of the hands face forward (anteriorly).

Proximal

A directional term meaning closer to the point of attachment.

Midsagittal Plane

A plane running vertically that divides the body into equal right and left halves.

Coronal / Frontal Plane

A body plane that divides the body into anterior (front) and posterior (back) portions.

Posterior / Dorsal Body Cavity

The body cavity formed by the cranial cavity and spinal cavity combined.

Diaphragm

The muscular structure that separates the thoracic cavity from the abdominopelvic cavity.

Mediastinum

The specific region within the thoracic cavity where the heart is located.

Liquid State

The state of matter that has a definite volume but takes the shape of its container.

Chemical Change

A change that transforms substances into new chemical identities, such as digesting food or fermenting grapes into wine.

Potential Energy

Stored energy that has the potential to do work.

Major Elements of the Human Body

The four major chemical elements making up the vast majority of human body mass: Oxygen, Carbon, Hydrogen, and Nitrogen.

Atomic Nucleus Particles

The subatomic particles located inside the nucleus of an atom: protons and neutrons.

Cation

A positively charged ion.

Covalent Bond

A chemical bond formed when atoms share electrons.

Activation Energy

The minimum amount of energy needed to trigger a chemical reaction.

Enzymes

Biological catalysts that speed up chemical reactions by lowering the required activation energy.

Body Water Percentage

Water accounts for up to $70\%$ of an adult human's total body weight.

Solvent and Solute

In a mixture, the dissolving liquid (e.g., water) is the solvent and the dissolved substance (e.g., salt) is the solute.

Acid

A chemical substance that releases hydrogen ions ($H^+$) when dissolved in water.

Arterial Blood pH Range

The normal pH range of human arterial blood, which is $7.35 - 7.45$.

pH Scale Factor

A change of 1 whole unit on the pH scale represents a 10-fold change in hydrogen ion concentration.

Buffers

Chemical compounds that resist drastic changes in pH.

Adenosine Triphosphate (ATP)

A high-energy molecule consisting of a ribose sugar, an adenine base, and three phosphate groups.

Carbohydrates

Organic compounds composed of Carbon, Hydrogen, and Oxygen elements.

Monosaccharides

Single-sugar carbohydrate units, including glucose, fructose, and galactose.

Glycosidic Bond

The covalent bond joining two monosaccharides together.

Glycogen Storage

Carbohydrates stored primarily as glycogen in the human body's liver and skeletal muscles.

Cellulose

An indigestible carbohydrate in humans that functions as dietary fiber.

Phospholipid

A lipid molecule composed of glycerol, a phosphate group, and two fatty acid chains.

Steroids

A class of lipids characterized by four hydrocarbon rings, with cholesterol being a primary example.

Omega-3 Fatty Acids

Fatty acids that improve cardiovascular health by stimulating prostaglandins to reduce blood pressure and inflammation.

Proteins

Polymers consisting of amino acids linked together by peptide bonds.

Keratin and Collagen

Structural proteins found in the skin; keratin is located in the epidermis and collagen in the dermis.

Active Site

The specific region on an enzyme where the substrate binds.

Protein Storage

There is no specialized storage site for excess protein in the human body other than functional tissues.

Thymine

A nitrogenous base found in DNA but absent in RNA.

RNA Characteristics

A nucleic acid that contains the sugar ribose and the base uracil instead of deoxyribose and thymine.

Purines

Nitrogenous bases with a double-ring chemical structure, consisting of Adenine and Guanine.