Unit 1 - Foundation Flashcards
levels of organization
chemical/molecular
cellular
tissue
chemical/molecular
atoms and molecules ( O, C, H, N, Ca, K, Na, Fe)
cellular
smallest level carrying out life functions
survival needed for all other levels
tissue
groups of cells with similar structure and function
four types - muscular, epithelial, connective and nervous
tissue types
- muscular
- nervous
- epithelial
- connective
Muscular tissue
generating force and movement
Nervous tissue
initiate and transmit electrical signals
Epithelial tissue
exchange material between cell and environment
sheets of tissue and secreting glands
Connective tissue
connects, support and anchors
Levels or organization
organ (combine 2 or more tissues)
System (collection of organs with similar function)
Organism (system interact with each other, human body
Environment of cell
cells in balance: fluid inside=fluid internal environment ICF external environment (cells not in contact with each other, ECF, plasma=fluid portion of blood, interstitial fluid)
Homeostasis
regulate internal conditions (need stable conditions within narrow limits, survive only within range
Process of maintaining this stability, maintained by negative and positive feedback system
Homeostatic control systems two types
Intrinsic controls
Extrinisic controls
Extrinsic controls
control outside organ
actions of nervous system (AP) and endocrine system(hormones)
intrinsic controls
local controls inside organ (food in stomach)
Components of homeostatic control system
- Sensor (receptor) cells detect deviation
- control centre (integrator) brain receives information and compares with normal set point, messages sent to muscles, glands or both
- Effector - muscle or gland responds to brain signals to restore homeostasis, feedback signals to sensor
Negative feedback
response in opposire direction of deviation, removes deviation, restores homeostasis
Positive feedback
response in same direction of deviation, reinforces deviation, uterine contractions become increasingly stronger until birth
Feedforward
anticipates change
occurs when a change is desired over time (digestive tract) insulin secreted to promote absorption of nutrients
Solutions
Mixture (2 or more atoms/molecules physically linked)
Solution ( chemical bonding solute [ substance dissolve in solvent] solvent [dissolving liquid]
Solutions and Electrolytes
solutes dissolve in liquids (electrolytes, charged ions in water - conduct electricity)
solubility, ease of dissolving
Hydrophobic
insoluble in water, repelled by water molecules
Hydrophilic
water soluble
Chemical reactions
breaking or forming chemical bonds
catalyst (enzymes) increases rate of reaction
Cations and anions
atoms may become ions lose electron (+) gain electron (-)
