Metabolism, homeostasis, +ve, -ve feedback Flashcards
metabolism
relates to the total of all chemical reactions occurring in an organism
anabolism
relates to the building of larger, more complex substances
catabolism
related to the breaking down of substances to gain energy, produces the raw materials for anabolism and to assist in creating substances to remove waste
homeostasis - state of balance
the condition of a relatively stable internal environment, maintained within narrow limits, in the face of external change
controlled variables include: HR, fluid balance, body temp, BP, CO2, ions/electrolytes, BGL, pH
negative feedback
a reaction in which the system responds to produce change in the opposite direction to the stimulus - ‘maintenance’
positive feedback
a reaction in which the system responds to produce change in the same direction to the stimulus - ‘amplifying’
systems to regulate HR
nervous
cardiovascular
60-100bpm
systems to regulate CO2
nervous
respiratory
systems to regulate fluid balance/blood volume
nervous
urinary
cardiovascular
light yellow
systems to regulate ions/electrolytes
nervous
urinary
cardiovascular
systems to regulate body temperature
nervous endocrine cardiovascular muscular integumentary 37*C
systems to regulate BGL
nervous
endocrine
cardiovascular
4-11mmol/L
systems to regulate Bp
nervous
cardiovascular
urinary
120/80
systems to regulate pH
nervous cardiovascular endocrine respiratory 7.35-7.45
positive feedback loop -> pregnancy
head of baby pushes against cervix;
nerve impulses from cervix transmitted to brain;
brain stimulates pituitary gland to secrete oxytocin;
oxytocin carried in bloodstream to uterus;
oxytocin stimulates uterine contractions and pushes baby towards cervix;
head of baby pushes against cervix -> thus amplifying response
