Chapter 2: Homeostasis Flashcards
Set point/set point range
Normal reading or range of normal
Autopoiesis
Life is self-organizing and self-maintaining
Level of organization smallest - largest
Chemical-organelle-cellular-tissue-organ-system-organism
5 types of cells
Neuron/glandular/RBC’s/muscle/immune
4 types of tissue
Epithelial/connective/muscle/nervous
Define “Form Fits Function”
Understanding The structure of something leads to clues to the function. If we do not understand the function how can we make anything better?
Ectomorph
Thin with little body fat
Endomorph
Heavyset. Accumulations of fat
Mesomorph
Muscular
Integumentary
Separates internal environment from external, providing stability of internal fluid volume.
Skeletal system
Supports and protects internal environment, allowing movement; stores minerals that can be moved into and out of internal fluid
Muscular system
Powers and directs movements; provides heat
Nervous system
Regulates homeostatic mechanisms sensing changes, integrating information, sending signals to effectors
Endocrine system
Homeostatic regulation by secreting signaling hormones that travel through internal environment to effector cells
Cardiovascular system
Maintains internal constancy by transporting nutrients, water, oxygen, hormones, wastes, and other materials and heat within internal environment
Lymphatic system
Maintains constant fluid pressure by draining excess fluid from tissues, cleaning it, and recycling it to bloodstream
Immune system
Defends internal environment against harmful agents
Respiratory system
Maintains stable oxygen and CO2 levels in body by exchanging these gases between external and internal environments; provides vocal communication with others for protection, hunting, etc.
Digestive system
Maintains relatively constant nutrient level by digesting food an absorbing nutrients into internal environment
Urinary system
Maintains constantly low level of waste and regulates pH of internal environment; helps maintain constancy of internal water volume and balance of ions and other substances
Reproductive system
Passes genetic code containing information for forming a body and maintaining homeostasis to offspring
Wallenda method compares homeostasis to what?
Home heating system controlled by a thermostat
Homeostatic control mechanisms
Processes for maintaining or restoring homeostasis
Feedback control loop
Highly complex and integrated communication control system or network
4 components of a feedback loop
1) sensor mechanism 2) integrator or control system 3) effector mechanism 4) Feedback
Afferent movement of a signal
Signal is traveling toward a particular center or point of reference
Efferent movement of a signal
Moving away from a point of reference
Variable
Any state or condition in the body that can change or very
Function of a SENSOR in a control system
Sensory nerve cells or endocrine glands that are able to identify the characteristics or condition being controlled. It can also respond to any changes that may occur from a normal set point range
Function of the INTEGRATOR or control center on a control system
Often a discrete area of the brain that receives input from a homeostatic sensor
What is an EFFECTOR?
Organs such as muscles or glands, that directly influence controlled physiological variables
What do Neg. Feedback loops do?
These control systems are inhibitory. They oppose or “negate” a change by creating a response that is opposite in direction to the initial disturbance. Responsible for maintaining a constant internal environment
What do Positive feedback loops do?
These do not operate to help the body maintain a stable, or homeostatic condition, it can be harmful to survival. These loops are stimulators. They amplify or reinforce the change that is occurring (oxytocin in labor)
Intracellular control
Mechanisms operating at cell level
Intrinsic control
Operating at tissue ad organ level
Extrinsic control
Operates at system and organism levels
