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BIOS 242 Final Exam Study Guide
in
Questions & Answers
1. Describe the organization of life (Cell->tissue->etc…) and describe the
characteristics of each unit.
a. Cell – smallest unit capable of exhibiting all of the characteristics of life
b. Tissue – group of cells with a common structure, function, and origin
i. Epithelial
ii. Muscle
iii. Nervous
iv. Connective
c. Organ – group of 2+ tissue types organized in such a way as to carry out a
particular function
i. Stomach
d. Organ system – group of 2+ organs organized in such a way as to carry
out a particular set of functions
i. Digestive system
e. Organism – sum total of organ system
2. Distinguish between the internal and external environment.
a. External environment – outside the body
b. Internal environment – inside the body but outside of the cell
i. Filled with extra-cellular fluid
1. Plasma
2. Interstitial fluid
3. There is free exchange between plasma and interstitial fluid
because the compositions are almost equal
3. Describe negative and positive feedback systems.
a. Negative feedback system – the response to a change in a controlled
variable is in opposition to the change
i. Go outside in cold body temp decreases shivering body
temp increases
ii. Go outside in heat body temp increase sweating body
temp decreases
iii. Most things maintained homeostatically are done by negative
feedback systems
b. Positive feedback system – the response to a change in a controlled
variable is in the same direction as the change
i. Smooth muscle of uterus contract sends signal to brain to
release hormone oxytocin oxytocin travels to uterus and causes
an increase in contractions sends another signal to brain to
release more oxytocin continues and leads to labor
, 2
4. Describe and discuss the 4 primary tissue types, including where they are
found, their structure, their functions, and their characteristics.
a. Connective tissue
i. Location – bones, blood, tendons, cartilage, and adipose
ii. Structure – contains an extensive ECM (secreted non-living
protein fibers in a carbohydrate soup) that can be fibrous, firm, or
liquid
iii. Function – binds, anchors, supports, and protects other tissues
and organs; transport
iv. Characteristics – contains proteins such as collagen (rigidity) and
elastin (elasticity)
b. Nervous tissue
i. Location – located in central and peripheral nervous systems
ii. Structure –
1. Glial cells – supporter cells that do not generate electricity
2. Neurons – main neural cells that transmit electrical signals
a. Dendrite, cell body, and axon
iii. Function – generates/transmits electrical signals
iv. Characteristics –
1. Spreads electrical signals through the release of
neurotransmitters
2. Electricity gets to end of neuron neurotransmitters are
released neurotransmitters either terminate on a muscle
cell (cause a contraction), on a gland (gland
action/secretion), or jump the synapse to another neuron
c. Muscle tissue
i. Location
1. Skeletal muscle – around bones
2. Smooth muscle – enclose hollow tubes and organs of the
body
3. Cardiac muscle – middle muscle layer of the heart
ii. Structure
1. Skeletal muscle – long; multinucleated; volunteer; cells
known as muscle fibers; striated tissue due to arrangement
of contractile proteins
2. Smooth muscle – no striations; one nucleus; involuntary
3. Cardiac muscle – short; may be branched; one nucleus;
involuntary; striated tissue due to arrangement of contractile
proteins; connected end-to-end by intercalated discs
iii. Function
, 3
1. Skeletal muscle – move bones
2. Smooth muscle – control movement through hollow tubes
and organs of the body it surrounds
3. Cardiac muscle – makes up contracting myocardium of heart
d. Epithelial tissue
i. Location – covering the body (skin) and lining the hollow tubes and
organs
ii. Structure – cells form sheets and are joined together by “tight
junctions”
1. Tight junction – nutrients/wastes cannot pass between cells,
but instead must go through cells and therefore be regulated
iii. Function – form barriers that regulate materials/wastes that
enter/exit cells and organs
1. Eg: lines the small intestine, which breaks down digested
food into absorbable units
iv. Characteristics – all glands are derived from epithelial tissue
1. Exocrine – secrete products into ducts, which eventually
secrete into hollow tubes/organs or to the outside of the
body
a. GI tract lumen is considered “external environment”
2. Endocrine – secrete their products (hormones) directly into
the bloodstream
3. Salivary – secrete saliva into mouth
5. Discuss homeostasis.
a. Homeostasis – the maintenance of a dynamic, steady state of the internal
environment
b. The internal environment must be maintained in such a way as to allow
the survival of the cells within
c. Most homeostatic values hover in a small range around a fixed point
i. Eg: blood vacillates between 7.35-7.45 pH
6. Describe and explain the processes of osmosis/diffusion.
a. Diffusion – movement of molecules from an area of higher concentration
to an area of lower concentration
i. Requires no active energy input, and instead uses the kinetic
energy of moving molecules
ii. Fick’s Laws of Diffusion
1. Concentration gradient – the greater the different between
the concentration of particles, the faster the rate of diffusion
2. Permeability – the higher the permeability of the membrane,
the faster the rate of diffusion
3. Surface area – the more surface area, the faster the rate of
diffusion
4. Molecular weight – the smaller the particle, the faster the
rate of diffusion
BIOS 242 Final Exam Study Guide
in
Questions & Answers
1. Describe the organization of life (Cell->tissue->etc…) and describe the
characteristics of each unit.
a. Cell – smallest unit capable of exhibiting all of the characteristics of life
b. Tissue – group of cells with a common structure, function, and origin
i. Epithelial
ii. Muscle
iii. Nervous
iv. Connective
c. Organ – group of 2+ tissue types organized in such a way as to carry out a
particular function
i. Stomach
d. Organ system – group of 2+ organs organized in such a way as to carry
out a particular set of functions
i. Digestive system
e. Organism – sum total of organ system
2. Distinguish between the internal and external environment.
a. External environment – outside the body
b. Internal environment – inside the body but outside of the cell
i. Filled with extra-cellular fluid
1. Plasma
2. Interstitial fluid
3. There is free exchange between plasma and interstitial fluid
because the compositions are almost equal
3. Describe negative and positive feedback systems.
a. Negative feedback system – the response to a change in a controlled
variable is in opposition to the change
i. Go outside in cold body temp decreases shivering body
temp increases
ii. Go outside in heat body temp increase sweating body
temp decreases
iii. Most things maintained homeostatically are done by negative
feedback systems
b. Positive feedback system – the response to a change in a controlled
variable is in the same direction as the change
i. Smooth muscle of uterus contract sends signal to brain to
release hormone oxytocin oxytocin travels to uterus and causes
an increase in contractions sends another signal to brain to
release more oxytocin continues and leads to labor
, 2
4. Describe and discuss the 4 primary tissue types, including where they are
found, their structure, their functions, and their characteristics.
a. Connective tissue
i. Location – bones, blood, tendons, cartilage, and adipose
ii. Structure – contains an extensive ECM (secreted non-living
protein fibers in a carbohydrate soup) that can be fibrous, firm, or
liquid
iii. Function – binds, anchors, supports, and protects other tissues
and organs; transport
iv. Characteristics – contains proteins such as collagen (rigidity) and
elastin (elasticity)
b. Nervous tissue
i. Location – located in central and peripheral nervous systems
ii. Structure –
1. Glial cells – supporter cells that do not generate electricity
2. Neurons – main neural cells that transmit electrical signals
a. Dendrite, cell body, and axon
iii. Function – generates/transmits electrical signals
iv. Characteristics –
1. Spreads electrical signals through the release of
neurotransmitters
2. Electricity gets to end of neuron neurotransmitters are
released neurotransmitters either terminate on a muscle
cell (cause a contraction), on a gland (gland
action/secretion), or jump the synapse to another neuron
c. Muscle tissue
i. Location
1. Skeletal muscle – around bones
2. Smooth muscle – enclose hollow tubes and organs of the
body
3. Cardiac muscle – middle muscle layer of the heart
ii. Structure
1. Skeletal muscle – long; multinucleated; volunteer; cells
known as muscle fibers; striated tissue due to arrangement
of contractile proteins
2. Smooth muscle – no striations; one nucleus; involuntary
3. Cardiac muscle – short; may be branched; one nucleus;
involuntary; striated tissue due to arrangement of contractile
proteins; connected end-to-end by intercalated discs
iii. Function
, 3
1. Skeletal muscle – move bones
2. Smooth muscle – control movement through hollow tubes
and organs of the body it surrounds
3. Cardiac muscle – makes up contracting myocardium of heart
d. Epithelial tissue
i. Location – covering the body (skin) and lining the hollow tubes and
organs
ii. Structure – cells form sheets and are joined together by “tight
junctions”
1. Tight junction – nutrients/wastes cannot pass between cells,
but instead must go through cells and therefore be regulated
iii. Function – form barriers that regulate materials/wastes that
enter/exit cells and organs
1. Eg: lines the small intestine, which breaks down digested
food into absorbable units
iv. Characteristics – all glands are derived from epithelial tissue
1. Exocrine – secrete products into ducts, which eventually
secrete into hollow tubes/organs or to the outside of the
body
a. GI tract lumen is considered “external environment”
2. Endocrine – secrete their products (hormones) directly into
the bloodstream
3. Salivary – secrete saliva into mouth
5. Discuss homeostasis.
a. Homeostasis – the maintenance of a dynamic, steady state of the internal
environment
b. The internal environment must be maintained in such a way as to allow
the survival of the cells within
c. Most homeostatic values hover in a small range around a fixed point
i. Eg: blood vacillates between 7.35-7.45 pH
6. Describe and explain the processes of osmosis/diffusion.
a. Diffusion – movement of molecules from an area of higher concentration
to an area of lower concentration
i. Requires no active energy input, and instead uses the kinetic
energy of moving molecules
ii. Fick’s Laws of Diffusion
1. Concentration gradient – the greater the different between
the concentration of particles, the faster the rate of diffusion
2. Permeability – the higher the permeability of the membrane,
the faster the rate of diffusion
3. Surface area – the more surface area, the faster the rate of
diffusion
4. Molecular weight – the smaller the particle, the faster the
rate of diffusion
