BIO 141 PSU EXAM 1 QUESTIONS
WITH CORRECT ANSWERS
Homeostasis - Correct Answers -body's ability to maintain constant environment
regulated by nervous and endocrine system
set point - Correct Answers -range of acceptable values of whatever is being maintained
(i.e. body temp)
feedback loops - Correct Answers -chain of reactions to maintain homeostasis
negative feedback loop - Correct Answers -body senses a change in condition and
negates that change to reverse or change the condition
positive feedback loop - Correct Answers -amplifying cycles in which a change leads to
the change being increase (i.e. oxytocin produced during labor causes more oxytocin to
be produced) and is used to cause rapid change. closely by negative feedback loops
organic molecules - Correct Answers -lipids, carbohydrates, proteins, nucleic acids
leak channels - Correct Answers -do not require energy but cannot diffuse directly
through a membrane
called channel mediated transport
gated channels - Correct Answers -only open at certain times/conditions
carrier mediated - Correct Answers -molecules that is moving binds to membrane
protein and changes its shape to allow molecules to pass through. ATP also must bind
to the protein
form of active transport
carbs - Correct Answers -functions: immediate energy
monomers: glucose and fructose
polymers: starch, celluslose, glycogen
lipids - Correct Answers -triglycerides
phospholipids
steroids
saturated
unsaturated
, triglycerides - Correct Answers -energy storage and insulation (long term)
consists of fatty acids and glycerol
phospholipids - Correct Answers -cell/organelle membranes
made of two fatty acids, a phosphate group, glycerol
fatty acid = hydrophobic
phosphate group = hydrophillic
steroids - Correct Answers -found in membranes and as hormones
derived from cholesterol
saturated fatty acid - Correct Answers -all single bonds (as much H as possible)
in meat and dairy
contributes to heart disease
unsaturated fatty acid - Correct Answers -contain single, double and/or triple bonds
omega fatty acids
Proteins - Correct Answers -polymer of amino acids
sequence of amino acids is primary structure which folds to make protein shape
diverse functions including enzymes and maintain homeostasis
function as hormones that are typically polar and/or anionic
Nucleic Acids - Correct Answers -ATP is the monomer consisting of adenine, a sugar,
and 3 phosphate groups
DNA consists of four nucleotides: adenine, thymine, guanine, cytosine
Gene expression - Correct Answers -DNA ---transcription--> RNA---translation---
>Protein RNA ---replication--->DNA
regulated
Plasma Membrane - Correct Answers -ions cannot diffuse because they have concrete
charge
small polar molecules can diffuse through the membrane
hydrophobic molecules can diffuse easily
Passive Transport - Correct Answers -does not require energy
diffusion requires concentration gradient (high concentration--->low concentration)
Channel Proteins - Correct Answers -form of passive transport
WITH CORRECT ANSWERS
Homeostasis - Correct Answers -body's ability to maintain constant environment
regulated by nervous and endocrine system
set point - Correct Answers -range of acceptable values of whatever is being maintained
(i.e. body temp)
feedback loops - Correct Answers -chain of reactions to maintain homeostasis
negative feedback loop - Correct Answers -body senses a change in condition and
negates that change to reverse or change the condition
positive feedback loop - Correct Answers -amplifying cycles in which a change leads to
the change being increase (i.e. oxytocin produced during labor causes more oxytocin to
be produced) and is used to cause rapid change. closely by negative feedback loops
organic molecules - Correct Answers -lipids, carbohydrates, proteins, nucleic acids
leak channels - Correct Answers -do not require energy but cannot diffuse directly
through a membrane
called channel mediated transport
gated channels - Correct Answers -only open at certain times/conditions
carrier mediated - Correct Answers -molecules that is moving binds to membrane
protein and changes its shape to allow molecules to pass through. ATP also must bind
to the protein
form of active transport
carbs - Correct Answers -functions: immediate energy
monomers: glucose and fructose
polymers: starch, celluslose, glycogen
lipids - Correct Answers -triglycerides
phospholipids
steroids
saturated
unsaturated
, triglycerides - Correct Answers -energy storage and insulation (long term)
consists of fatty acids and glycerol
phospholipids - Correct Answers -cell/organelle membranes
made of two fatty acids, a phosphate group, glycerol
fatty acid = hydrophobic
phosphate group = hydrophillic
steroids - Correct Answers -found in membranes and as hormones
derived from cholesterol
saturated fatty acid - Correct Answers -all single bonds (as much H as possible)
in meat and dairy
contributes to heart disease
unsaturated fatty acid - Correct Answers -contain single, double and/or triple bonds
omega fatty acids
Proteins - Correct Answers -polymer of amino acids
sequence of amino acids is primary structure which folds to make protein shape
diverse functions including enzymes and maintain homeostasis
function as hormones that are typically polar and/or anionic
Nucleic Acids - Correct Answers -ATP is the monomer consisting of adenine, a sugar,
and 3 phosphate groups
DNA consists of four nucleotides: adenine, thymine, guanine, cytosine
Gene expression - Correct Answers -DNA ---transcription--> RNA---translation---
>Protein RNA ---replication--->DNA
regulated
Plasma Membrane - Correct Answers -ions cannot diffuse because they have concrete
charge
small polar molecules can diffuse through the membrane
hydrophobic molecules can diffuse easily
Passive Transport - Correct Answers -does not require energy
diffusion requires concentration gradient (high concentration--->low concentration)
Channel Proteins - Correct Answers -form of passive transport
