Chapter 1: Intro to the human body Flashcards
6 levels of structural organization
- Chemical
- Cellular
- Tissue
- Organ
- System
- Organismal
What is the Chemical Level of organization
Atoms (the smallest units of matter) and molecules (2+ atoms joined together)
What is the Cellular Level of organization
Molecules combine to form cells (the basic structural and functional units of an organism that are composed of chemicals)
What is the Tissue Level of organization
Groups of cells and the materials surrounding them that perform a particular fxn
What is the Organ Level of organization
Composed of 2+ different types of tissues and have specific fxns and typically recognizable shapes
What is the System Level of organization
Consists of related organs with a common fxn
What is the Organismal Level of organization
All the parts of the human body functioning together
4 types of tissue
- Epithelial
- Connective
- Muscular
- Nervous
6 basic life processes
- Metabolism = catabolism & anabolism
- Responsiveness = body’s ability to detect and respond to changes
- Movement
- Growth = increase in body size that results from an increase in the size of existing cells, an increase in the # of cells or both
- Differentiation = the development of a cell from an unspecialized to specialized state
- Reproduction = formation of new cells OR production of new individual
Catabolism
Breakdown of complex chemical substances into simpler components
Anabolism
Building of complex chemical substances from smaller, simpler components
Homeostasis
A dynamic condition; the maintenance of relatively stable conditions in the body’s internal environment
Body fluids
Dilute, watery solutions containing dissolved chemicals that are found inside cells and surrounding them
2 types of fluid
- ICF (within cells)
- ECF (surrounds cells)
Interstitial fluid
ECF that fills the narrow spaces between the cells of tissues (e.g., blood plasma, lymph, synovial fluid)
How the cardiovascular system contributes to homeostasis
Transports O2 and nutrients through the body:
- O2 and nutrients diffuse into interstitial fluid via blood capillaries
- O2 and nutrients are taken up by cells and metabolized for energy
- During metabolization, cells produce waste which enter interstitial fluid and move across blood capillary walls into plasma
- Cardiovascular system transports waste to the appropriate organ for elimination to the external environment
2 regulatory systems to control homeostasis
- Nervous system
- Endocrine system
What does the nervous system do
Sends electrical signals (nerve impulses or action potentials) to organs that counteract (quick change)
What does the endocrine system do
Glands secrete messenger molecules called hormones into the blood (slow change)
Feedback systems (loops)
A cycle of events in which the status of a body condition is monitored, evaluated, changed, monitored, reevaluated, etc.
3 basic components of feedback systems
- Receptor
- Control center
- Effector
Receptor (afferent pathway)
body structure that monitors changes in a controlled condition and sends inputs to a control center
Control center (efferent pathway)
Sets the narrow range within which a controlled condition should be maintained, evaluates the input it receives from receptors, and generates output commands when they are needed
Effector
Body structure that receive outputs from the control center and produces a response or effect that changes the controlled condition
Negative feedback
Reverses a change in a controlled condition (regulate conditions that remain stable over long periods, e.g., blood pressure)
Positive feedback
Strengthens or reinforces a change in one of the body’s controlled conditions (reinforce conditions that don’t happen often, e.g., childbirth)
