Living Systems and Biological Organization Vocabulary

50 vocabulary flashcards covering living systems, biological organization, homeostasis, feedback mechanisms, biomolecules, and membrane structures based on lecture notes.

Metabolism

All chemical processes that occur within a living system.

Catabolism

Chemical processes that break down large molecules into small molecules, providing energy for cellular processes.

Anabolism

Chemical processes that build small molecules into large molecules to bulk up.

Responsiveness

The ability of a living system to detect and respond to changes in its environment.

Growth

An increase in size or number of cells, or the amount of material between cells.

Differentiation

Cell specialization to perform a specific function.

Reproduction

The formation of new cells.

Chemical level

The level of biological organization consisting of non-living atoms and molecules.

Cellular level

The structural level of biological organization consisting of living cells.

Tissue level

A level of biological organization consisting of a group of living cells and materials around them working together.

Organ level

A structural level composed of groups of tissues organized into a structure with a specific function.

Organ System level

A collection of organs with a common function.

Organismic level

The highest level of biological organization, representing a living individual.

Dehydration

Fluid loss from the body.

Anhidrosis

A condition that inhibits sweat, requiring water to be sprayed on the body to allow fluid to leave.

Homeostasis

The condition in which the body's internal environment remains relatively constant within physiological limits.

Stimulus

A change in the controlled condition of the internal environment.

Receptor

A sensor in a feedback loop that detects and responds to changes in controlled conditions.

Control Center

The decision-making component of a feedback loop.

Effector

The component of a feedback loop that receives output and tells or makes the response happen.

Negative feedback loop

A feedback mechanism where the original stimulus is reversed, used for systems requiring frequent adjustment.

Positive feedback loop

A feedback mechanism where the original stimulus is intensified.

Steady state

A condition of homeostasis where a relatively constant state is maintained over time using energy.

Equilibrium

A state characterized by constant change without using energy.

Set point

The stable mean of a controlled condition maintained by feedback loops.

Oxytocin

A hormone produced by the pituitary gland (referred to as the love hormone) that causes increased uterine contractions.

Enzyme

A biological catalyst that increases reaction rate by lowering activation energy.

Activation energy

The energy barrier for a chemical reaction, which enzymes lower by bringing substrates together in the correct orientation and reducing collision randomness.

Solvent

The dissolving liquid in an aqueous solution, such as water, which makes up $60\%$ of the human body.

Solute

Substances dissolved within a solvent.

Intracellular fluid (ICF)

All fluid located within cells.

Extracellular fluid (ECF)

All fluid located outside of cells.

Interstitial fluid (ISF)

Extracellular fluid occupying the spaces between cells.

Plasma (intravascular fluid)

The liquid portion of blood.

Nonpolar covalent bond

A chemical bond characterized by equal sharing of electrons between atoms.

Polar covalent bond

A chemical bond characterized by unequal sharing of electrons, resulting in partial positive and negative charges.

Hydrophilic molecules

Water-loving polar molecules that can dissolve in water.

Hydrophobic molecules

Water-fearing nonpolar molecules that cannot dissolve in water.

Amphipathic molecules

Molecules that contain both hydrophilic (polar) and hydrophobic (nonpolar) regions.

Emulsify

To mix two liquids together that usually do not mix.

Carbohydrates

Biomolecules that function as a primary energy source, provide energy storage, and make extracellular matrix structures.

Lipids

Biomolecules that store energy, provide structure/support, and make hormones.

Proteins

Biomolecules responsible for cell functions and structures, as well as muscle contraction.

Nucleic acid

Biomolecules responsible for heredity, protein structure, and high energy phosphates like ATP.

Adenosine triphosphate (ATP)

A high-energy molecule consisting of adenine, ribose, and 3 phosphate groups that releases energy upon hydrolysis.

Cholesterol

A lipid embedded within the phospholipid bilayer that regulates membrane stability and fluidity.

Integral membrane proteins

Amphipathic proteins embedded within the phospholipid bilayer whose non-polar regions interact with non-polar fatty acid tails.

Peripheral membrane proteins

Non-amphipathic membrane proteins located on the surface that interact with polar heads of lipids and are easily removed.

Micelle

A single layer structure of surfactant or membrane with a hydrophobic core.

Liposome

A double-layered membrane structure with an aqueous core, hydrophobic middle, and hydrophilic surface.