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4 tissue types in the body:
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4 tissue types in the body:Epithelial - covers the surface of the body
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4 tissue types in the body:Epithelial - covers the surface of the body
Connective - tough and flexible protein fibers, acts likean organic glue
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4 tissue types in the body:Epithelial - covers the surface of the body
Connective - tough and flexible protein fibers, acts likean organic glue
Muscle - Interacts with hairs to respond to stimuli suchas cold and fright
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4 tissue types in the body:Epithelial - covers the surface of the body
Connective - tough and flexible protein fibers, acts likean organic glue
Muscle - Interacts with hairs to respond to stimuli suchas cold and fright
Nervous - Allows us to detect external stimuli (pain,
pressure etc)
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2 layers:
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2 layers:Epidermis
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2 layers:Epidermis
Dermis
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Exterior portion
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Exterior portion25 - 30 layers of dead
flattened cells
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Exterior portion25 - 30 layers of dead
flattened cellsContains keratin: protects and
gives elasticity
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Exterior portion25 - 30 layers of dead
flattened cellsContains keratin: protects and
gives elasticity
Interior portion
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Exterior portion25 - 30 layers of dead
flattened cellsContains keratin: protects and
gives elasticity
Interior portionLiving cells that replace
the dead cells
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Exterior portion25 - 30 layers of dead
flattened cellsContains keratin: protects and
gives elasticity
Interior portionLiving cells that replace
the dead cellsSome contain melanin - colors
the skin. Protects cells fromdamage
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Exterior portion25 - 30 layers of dead
flattened cellsContains keratin: protects and
gives elasticity
Interior portionLiving cells that replace
the dead cellsSome contain melanin - colors
the skin. Protects cells fromdamage
Takes about 28 days
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Thicker than theEpidermis
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Thicker than theEpidermisThickness varied in different parts
of the body
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Thicker than theEpidermisThickness varied in different parts
of the body
Contains blood vessels,nerves, nerve endings,
hair follicles, sweatglands and oil glands.
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Thicker than theEpidermisThickness varied in different parts
of the body
Contains blood vessels,nerves, nerve endings,
hair follicles, sweatglands and oil glands.
Oil glands
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Thicker than theEpidermisThickness varied in different parts
of the body
Contains blood vessels,nerves, nerve endings,
hair follicles, sweatglands and oil glands.
Oil glandsPrevents hair from drying out.
Keeps skin soft. Inhibits bacteria
growth
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Hair follicles
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Hair folliclesNarrow cavities out of which
hair grows
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Hair folliclesNarrow cavities out of which
hair grows
Sweat Glands
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Hair folliclesNarrow cavities out of which
hair grows
Sweat GlandsAverage human looses 900mL
of sweat/day
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Regulates internal bodytemperature
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Regulates internal bodytemperature
Sweat is released in response to
elevated body temperature
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Regulates internal bodytemperature
Sweat is released in response to
elevated body temperature
As sweat evaporates, the body
cools
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Regulates internal bodytemperature
Sweat is released in response to
elevated body temperature
As sweat evaporates, the body
cools
Functions as a sense
organ
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Regulates internal bodytemperature
Sweat is released in response to
elevated body temperature
As sweat evaporates, the body
cools
Functions as a sense
organNerve cells receive stimuli from
outside and relays information
on the inside
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Produces vitamins
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Produces vitaminsVitamin D - when exposed to light.
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Produces vitaminsVitamin D - when exposed to light.
Helps the blood absorb Calcium
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Produces vitaminsVitamin D - when exposed to light.
Helps the blood absorb Calcium
Protects the underlying tissues
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Produces vitaminsVitamin D - when exposed to light.
Helps the blood absorb Calcium
Protects the underlying tissues
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Repair stages (inresponse to injury):
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Repair stages (inresponse to injury):
Blood flows to the wound untila clot forms
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Repair stages (inresponse to injury):
Blood flows to the wound untila clot forms
Scab develops (barrierbetween bacteria andunderlying tissues
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Repair stages (inresponse to injury):
Blood flows to the wound untila clot forms
Scab develops (barrierbetween bacteria andunderlying tissues
New skin cells repair thewound from beneath
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The Structure of the Skeletal System
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The Structure of the Skeletal SystemThe Formation of the Skeletal System
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The Structure of the Skeletal SystemThe Formation of the Skeletal System
The Function of the Skeletal System
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The Structure of the Skeletal SystemThe Formation of the Skeletal System
The Function of the Skeletal System
Bone injury and disease
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The adult human skeletoncontains approximately206 bones
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The adult human skeletoncontains approximately206 bones
2 main parts:
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The adult human skeletoncontains approximately206 bones
2 main parts:The Axial Skeleton:
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The adult human skeletoncontains approximately206 bones
2 main parts:The Axial Skeleton:
The skull and the bones thatsupport it (vertebral column,
ribs, sternum)
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The adult human skeletoncontains approximately206 bones
2 main parts:The Axial Skeleton:
The skull and the bones thatsupport it (vertebral column,
ribs, sternum)
The Appendicular Skeleton
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The adult human skeletoncontains approximately206 bones
2 main parts:The Axial Skeleton:
The skull and the bones thatsupport it (vertebral column,
ribs, sternum)
The Appendicular SkeletonBones of the arms and legs and
structures associated with them
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Where two or more bonesmeet
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Where two or more bonesmeet
Usually facilitate movement
of bones in relation to oneanother (not the joints ofthe skull)
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Where two or more bonesmeet
Usually facilitate movement
of bones in relation to oneanother (not the joints ofthe skull)
Held together and enclosedby ligaments
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Where two or more bonesmeet
Usually facilitate movement
of bones in relation to oneanother (not the joints ofthe skull)
Held together and enclosedby ligaments
Tough band of connective tissue
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Two types of bone tissue
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Two types of bone tissueCompact bone: layer of hard
bone that surrounds every
bone
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Two types of bone tissueCompact bone: layer of hard
bone that surrounds every
bone
Composed of osteon systems
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Two types of bone tissueCompact bone: layer of hard
bone that surrounds every
bone
Composed of osteon systemsOsteocytes: living bone cells.
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Two types of bone tissueCompact bone: layer of hard
bone that surrounds every
bone
Composed of osteon systemsOsteocytes: living bone cells.
Receive O2 and nutrients from small
blood vessels within osteonsystem
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Two types of bone tissueCompact bone: layer of hard
bone that surrounds every
bone
Composed of osteon systemsOsteocytes: living bone cells.
Receive O2 and nutrients from small
blood vessels within osteonsystem
Nerves conduct impulses to andfrom each cell
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Two types of bone tissueCompact bone: layer of hard
bone that surrounds every
bone
Composed of osteon systemsOsteocytes: living bone cells.
Receive O2 and nutrients from small
blood vessels within osteonsystem
Nerves conduct impulses to andfrom each cell
Spongy bone: less dense bone,filled with holes and spaces
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In embryo, the vertebrateskeleton is made ofcartilage
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In embryo, the vertebrateskeleton is made ofcartilage
By week 9, bone begins
to replace the cartilage
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In embryo, the vertebrateskeleton is made ofcartilage
By week 9, bone begins
to replace the cartilageBlood vessels penetrate
the cartilage and the
cells becomeosteoblasts (potentialbone cells)
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Osteoblasts secrete theprotein collagenDeposits minerals (i.e. calcium) in
the bloodstream
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Osteoblasts secrete theprotein collagenDeposits minerals (i.e. calcium) in
the bloodstream
Calcium salts and otherions cause theosteoblasts to hardenand become osteocytes
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Growth in Length:
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Growth in Length:Occurs at the ends of bones in cartilage plates
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Growth in Length:Occurs at the ends of bones in cartilage plates
Growth in Diameter (thickness)
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Growth in Length:Occurs at the ends of bones in cartilage plates
Growth in Diameter (thickness)
Occurs at the outer surface of the bone
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Growth in Length:Occurs at the ends of bones in cartilage plates
Growth in Diameter (thickness)
Occurs at the outer surface of the boneAccelerated by Sex hormones during
teen years.
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Provides framework for the tissues in ourbodies
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Provides framework for the tissues in ourbodies
Protects internal organs
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Provides framework for the tissues in ourbodies
Protects internal organs
Produce Blood cells
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Provides framework for the tissues in ourbodies
Protects internal organs
Produce Blood cellsRed marrow: produces red blood cells, white blood cells
and cell fragments for clotting
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Provides framework for the tissues in ourbodies
Protects internal organs
Produce Blood cellsRed marrow: produces red blood cells, white blood cells
and cell fragments for clotting
Yellow marrow: Stores fat
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Provides framework for the tissues in ourbodies
Protects internal organs
Produce Blood cellsRed marrow: produces red blood cells, white blood cells
and cell fragments for clotting
Yellow marrow: Stores fat
Stores minerals, including calcium andphosphates
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Provides framework for the tissues in ourbodies
Protects internal organs
Produce Blood cellsRed marrow: produces red blood cells, white blood cells
and cell fragments for clotting
Yellow marrow: Stores fat
Stores minerals, including calcium andphosphates
Needed to form strong, healthy bones.
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Osteoporosis
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OsteoporosisLoss of bone volume
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OsteoporosisLoss of bone volume
Bones become more porous andbrittle
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OsteoporosisLoss of bone volume
Bones become more porous andbrittle
Broken bones
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OsteoporosisLoss of bone volume
Bones become more porous andbrittle
Broken bonesShown by X-ray images
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OsteoporosisLoss of bone volume
Bones become more porous andbrittle
Broken bonesShown by X-ray images
Bones are moved back into
position and immobilized sothe bone can regrow
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21
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The Structure of the Skeletal System
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The Structure of the Skeletal SystemThe Formation of the Skeletal System
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The Structure of the Skeletal SystemThe Formation of the Skeletal System
The Function of the Skeletal System
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The Structure of the Skeletal SystemThe Formation of the Skeletal System
The Function of the Skeletal System
Bone injury and disease
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The 3 Types of Muscles
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The 3 Types of MusclesHow Muscles Work
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The 3 Types of MusclesHow Muscles Work
Muscles during Exercise
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Smooth muscle
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
Found ONLY in the heart
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
Found ONLY in the heart
Interconnected to form a network to help
muscle cells contract efficiently
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
Found ONLY in the heart
Interconnected to form a network to help
muscle cells contract efficiently
Adapted to generate and conduct electricalimpulses
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
Found ONLY in the heart
Interconnected to form a network to help
muscle cells contract efficiently
Adapted to generate and conduct electricalimpulses
Skeletal muscle
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
Found ONLY in the heart
Interconnected to form a network to help
muscle cells contract efficiently
Adapted to generate and conduct electricalimpulses
Skeletal muscle
Attached to and moves bones
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Smooth muscle
Found in the walls of internal organs (i.e.organs of the digestive tract) and blood
vessels
Also called involuntary muscle (not underconscious control)
Cardiac muscle
Found ONLY in the heart
Interconnected to form a network to help
muscle cells contract efficiently
Adapted to generate and conduct electricalimpulses
Skeletal muscle
Attached to and moves bones
Also called voluntary muscle (under
conscious control)
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The majority of
skeletal
muscles workin opposing
pairs
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Muscle tissue is made up of musclefibers (long fused muscle cells)
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Muscle tissue is made up of musclefibers (long fused muscle cells)Each fiber is made up of myofibrils (2 kinds):
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Muscle tissue is made up of musclefibers (long fused muscle cells)Each fiber is made up of myofibrils (2 kinds):
Thick filament (myosin)
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Muscle tissue is made up of musclefibers (long fused muscle cells)Each fiber is made up of myofibrils (2 kinds):
Thick filament (myosin)
Thin filament (actin)
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Muscle tissue is made up of musclefibers (long fused muscle cells)Each fiber is made up of myofibrils (2 kinds):
Thick filament (myosin)
Thin filament (actin)
Appears striated (striped)
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Sarcomeres: functional unit of contraction
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Sarcomeres: functional unit of contraction
Muscles contract according to the sliding
filament theory
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Sarcomeres: functional unit of contraction
Muscles contract according to the sliding
filament theory
Myosin heads pull against the actin filaments and
actin filaments slide toward one another
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Sarcomeres: functional unit of contraction
Muscles contract according to the sliding
filament theory
Myosin heads pull against the actin filaments and
actin filaments slide toward one anotherSarcomere shortens
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Image by: David Richfield
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The number of muscle cells are fixed attime of birth
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The number of muscle cells are fixed attime of birth
Working out makes you stronger, but you
don
t get more muscle
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The number of muscle cells are fixed attime of birth
Working out makes you stronger, but you
don
t get more muscleMuscle fibers increase in diameter in
response to regular exercise
Muscle contraction required ATP
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During exercise, muscles use oxygen
(aerobic respiration)
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During exercise, muscles use oxygen
(aerobic respiration)
This eventually shifts to anaerobic
respiration and lactic acid is produced
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During exercise, muscles use oxygen
(aerobic respiration)
This eventually shifts to anaerobic
respiration and lactic acid is produced
Lactic acid builds up. As you catch your
breath, more oxygen is delivered and
lactic acid is broken down
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During exercise, muscles use oxygen
(aerobic respiration)
This eventually shifts to anaerobic
respiration and lactic acid is produced
Lactic acid builds up. As you catch your
breath, more oxygen is delivered and
lactic acid is broken down
Regular exercise results in improved
performance of muscles
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The 3 Types of Muscles
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The 3 Types of Muscles
How Muscles Work
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The 3 Types of Muscles
How Muscles Work
Muscles during Exercise