Biol2220 Final Exam QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY
GRADED A+
Homeostasis - correct answer Maintenance of relatively constant conditions in the internal
environment
Significance of Homeostasis - correct answer Disruption can lead to disease; Body can adapt to
mild stressors; Variables that need to remain constant: composition, temperature, volume
Positive Feedback Loops - correct answer Positive Feedback: the response of system goes in the
same direction as the change
Negative Feedback Loops - correct answer Negative Feedback: [definition not provided]
Cellular Signalling - correct answer Specialised cells → tissues → organs; Communication via
transmitters allows functioning; Involves gap junctions and cell-to-cell interactions
Juxtacrine Signalling - correct answer Direct contact between cells; Gap junctions
Paracrine Signalling - correct answer Short distance, immediate cellular environment; Local
coordination (proliferation and differentiation)
Autocrine Signalling - correct answer Cell signals to self; Self-stimulation (immune system) or
self-identity (development)
Endocrine Signalling - correct answer To distant sites, via hormones in the bloodstream;
Development and physiology
Processes in Cell Signalling - correct answer Paracrine: signal received from presynaptic neuron
on nearby postsynaptic neuron; Autocrine: signal sent + received by presynaptic neuron
Neuroendocrine Signalling - correct answer Neurosecretory neurons release neurohormones
Nervous System Communication - correct answer Wired signals, travel by neural connection
Endocrine System Communication - correct answer Wireless signals, travel via blood stream
(hormones)
Chemical Signals - correct answer Neurotransmitters, growth factors, metabolites, hormones,
ECM components, ions
Receptors - correct answer Bind to initiate a physiological response - transmit through
sequences of molecular switches to signalling pathways
Gap Junctions - correct answer Formed when 2 connexons adjacently come together to form a
narrow pore between cells - allowing small molecules and ions to move from cell to cell
providing metabolic and electrical coupling
Hormones - correct answer Produced in specialised cells/organs, travel via blood
Endocrine Glands - correct answer Have specialised cells, produce hormones
, Biol2220 Final Exam QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY
GRADED A+
Target Organs/Tissues - correct answer Must have specific receptors, circulating hormones will
contact, only some respond
Steroid Hormones - correct answer Derived from lipid cholesterol
Peptide-Protein Hormones - correct answer Long amino chains or short linked chains
Amine Hormones - correct answer Modified amino
Hormone Actions - correct answer Synthesised and released (stored in vesicles/released as
synthesised); Transported in blood (protein (un)bound); Received at cell (intra/extra-cellular);
Elicit cell actions and responses (rapid/slow/sustained/cyclical/pulsatile)
Signal Transduction - correct answer Classical Genomic Signalling: lipophilic - can diffuse across
membrane + interact with receptors inside cell; Non-Genomic Signalling: extracellular receptors
(GPCRs) have been identified - exact contributions not well understood
Types of Receptors - correct answer G-protein coupled; Ion channel; Enzyme-linked; [can be
ligand-gated channels]
G-Proteins and Signal Transduction - correct answer No hormone = GDP is bound to α subunit
of G protein; Hormone attaches to receptor = regulatory components (β & γ) detach from α and
GDP bound to α is exchanged for GPT; Activated α alters function of another membrane protein
usually a channel/enzyme (adenylate cyclase, phospholipase C)
Primary Endocrine Organs - correct answer Pituitary gland, pineal gland, thyroid gland,
parathyroid glands, thymus, pancreas, gonads
Secondary Endocrine Organ - correct answer Secretes hormone + carries out another primary
function e.g. heart, liver, kidneys
Endocrine Hormones - correct answer Tropic hormone: controls secretion of other hormones
e.g. hypothalamus/thyroid; Stimulating hormone: increases hormone secretion; Inhibiting
hormone: decrease hormone secretion
Endocrinology Axes - correct answer Hypothalamus releases trophic hormone → effects release
of another → that one effects release of 3rd → 3rd effects target cells throughout the body
Functional Types of Neurons in CNS - correct answer Neurons: made up of cell body, dendrites
and axon; Sensory (afferent): detect/transduce stimuli arising from outside/inside → CNS;
Motor (efferent): carry efferent signals from CNS to effector to cause a change; Interneurons:
connect neurons to one another in CNS, allow CNS to communicate, form circuits for processing
neural information
Functional Types of Glial Cells in CNS and PNS - correct answer Neuroglia: Functions: physical
support, supply nutrients and o2, electrical insulation, destroy pathogens, information
processing; Types: astrocytes, oligodendrocytes + schwann cells, microglia, ependymal cells
GRADED A+
Homeostasis - correct answer Maintenance of relatively constant conditions in the internal
environment
Significance of Homeostasis - correct answer Disruption can lead to disease; Body can adapt to
mild stressors; Variables that need to remain constant: composition, temperature, volume
Positive Feedback Loops - correct answer Positive Feedback: the response of system goes in the
same direction as the change
Negative Feedback Loops - correct answer Negative Feedback: [definition not provided]
Cellular Signalling - correct answer Specialised cells → tissues → organs; Communication via
transmitters allows functioning; Involves gap junctions and cell-to-cell interactions
Juxtacrine Signalling - correct answer Direct contact between cells; Gap junctions
Paracrine Signalling - correct answer Short distance, immediate cellular environment; Local
coordination (proliferation and differentiation)
Autocrine Signalling - correct answer Cell signals to self; Self-stimulation (immune system) or
self-identity (development)
Endocrine Signalling - correct answer To distant sites, via hormones in the bloodstream;
Development and physiology
Processes in Cell Signalling - correct answer Paracrine: signal received from presynaptic neuron
on nearby postsynaptic neuron; Autocrine: signal sent + received by presynaptic neuron
Neuroendocrine Signalling - correct answer Neurosecretory neurons release neurohormones
Nervous System Communication - correct answer Wired signals, travel by neural connection
Endocrine System Communication - correct answer Wireless signals, travel via blood stream
(hormones)
Chemical Signals - correct answer Neurotransmitters, growth factors, metabolites, hormones,
ECM components, ions
Receptors - correct answer Bind to initiate a physiological response - transmit through
sequences of molecular switches to signalling pathways
Gap Junctions - correct answer Formed when 2 connexons adjacently come together to form a
narrow pore between cells - allowing small molecules and ions to move from cell to cell
providing metabolic and electrical coupling
Hormones - correct answer Produced in specialised cells/organs, travel via blood
Endocrine Glands - correct answer Have specialised cells, produce hormones
, Biol2220 Final Exam QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY
GRADED A+
Target Organs/Tissues - correct answer Must have specific receptors, circulating hormones will
contact, only some respond
Steroid Hormones - correct answer Derived from lipid cholesterol
Peptide-Protein Hormones - correct answer Long amino chains or short linked chains
Amine Hormones - correct answer Modified amino
Hormone Actions - correct answer Synthesised and released (stored in vesicles/released as
synthesised); Transported in blood (protein (un)bound); Received at cell (intra/extra-cellular);
Elicit cell actions and responses (rapid/slow/sustained/cyclical/pulsatile)
Signal Transduction - correct answer Classical Genomic Signalling: lipophilic - can diffuse across
membrane + interact with receptors inside cell; Non-Genomic Signalling: extracellular receptors
(GPCRs) have been identified - exact contributions not well understood
Types of Receptors - correct answer G-protein coupled; Ion channel; Enzyme-linked; [can be
ligand-gated channels]
G-Proteins and Signal Transduction - correct answer No hormone = GDP is bound to α subunit
of G protein; Hormone attaches to receptor = regulatory components (β & γ) detach from α and
GDP bound to α is exchanged for GPT; Activated α alters function of another membrane protein
usually a channel/enzyme (adenylate cyclase, phospholipase C)
Primary Endocrine Organs - correct answer Pituitary gland, pineal gland, thyroid gland,
parathyroid glands, thymus, pancreas, gonads
Secondary Endocrine Organ - correct answer Secretes hormone + carries out another primary
function e.g. heart, liver, kidneys
Endocrine Hormones - correct answer Tropic hormone: controls secretion of other hormones
e.g. hypothalamus/thyroid; Stimulating hormone: increases hormone secretion; Inhibiting
hormone: decrease hormone secretion
Endocrinology Axes - correct answer Hypothalamus releases trophic hormone → effects release
of another → that one effects release of 3rd → 3rd effects target cells throughout the body
Functional Types of Neurons in CNS - correct answer Neurons: made up of cell body, dendrites
and axon; Sensory (afferent): detect/transduce stimuli arising from outside/inside → CNS;
Motor (efferent): carry efferent signals from CNS to effector to cause a change; Interneurons:
connect neurons to one another in CNS, allow CNS to communicate, form circuits for processing
neural information
Functional Types of Glial Cells in CNS and PNS - correct answer Neuroglia: Functions: physical
support, supply nutrients and o2, electrical insulation, destroy pathogens, information
processing; Types: astrocytes, oligodendrocytes + schwann cells, microglia, ependymal cells
