Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
292 Cards in this Set
- Front
- Back
|
What makes up tissues?
|
A. Cells
B. Many Cells make tissue which makes organs. |
|
|
Cells Perform life skills….
|
Growth
Metabolism Response to Stimuli Contraction Reproduction |
|
|
What are the primary animal tissues?
|
Epithelial Tissue
1. Covers External/Internal Surfaces 2. Body Lining Outside skin |
|
|
Connective Tissue
|
1. Sheets/ Bundle – holding structures
2. Part of skeletal system (ligaments) 3. Forms/ surrounds muscle bundles - |
|
|
Muscular Tissue
|
1. Most common
2. Specialize in contraction |
|
|
Nervous Tissue
|
1. Conduct impulses/receive stimulus from one part of the body to another
2. Neurons = nervous cell 3. Dendrites = connect cell body and conducts impulses toward cell body 4. Axons= send impulses away from the cell body |
|
|
epithelial tissue?
|
Simple(single layered)
Stratified(multilayered) |
|
|
Simple(single layerera
Stratified(multilayered) |
1. Found in blood vessels, ducts of glands, intestines, trachea, upper respiratory.
2. Forms outer skin layer, first part of digestive tract areas subject to stretching, hormonal glands, base of skull, bone marrow. |
|
|
What are the type of connective tissue?
|
Collagenous
Regular tissue Irregular connective tissue Loose Tissue Adipose Cartilage |
|
|
Collagenous –
|
found throughout the body, very strong, arranged in repeating units
|
|
|
Regular tissue –
|
tendons/ligaments
|
|
|
Irregular connective tissue =
|
thick mat running on all directions – tanning leather
|
|
|
Loose Tissue =
|
cushion and flexibility
|
|
|
Adipose –
|
fat cells (white and brown)
|
|
|
Cartilage =
|
firm tissue – not as hard ar bone
|
|
|
Bone – Osteoblasts =
|
bones cells
|
|
|
Blood –
|
sometimes connective – because of origin
|
|
|
RBC –
|
erythrocytes contain hemoglobin (carries oxygen from the lungs to tissue of all animals)
|
|
|
WBC –
|
Leukocytes – fight infection
|
|
|
Plasma
|
fluid part of unclotted blood
|
|
|
Bone – Osteoblasts =
|
bones cells
|
|
|
Blood –
|
sometimes connective – because of origin
|
|
|
RBC –
|
erythrocytes contain hemoglobin (carries oxygen from the lungs to tissue of all animals)
|
|
|
WBC – Leukocytes –
|
fight infection
|
|
|
Serum –
|
remains after clot – lack clotting factors
|
|
|
Plasma –
|
fluid part of unclotted blood
|
|
|
Platelets –
|
clots blood
|
|
|
What are the 3 types of muscular tissue?
|
Striated
Skeletal Smooth |
|
|
C. Smooth-
|
Involuntary = muscle found in intestines and reproductive tract.
|
|
|
B. Striated-
|
Involuntary = cardiac
|
|
|
Skeletal-Voluntary =
|
skeletal muscles
|
|
|
What are the three types of nervous tissue?
|
Sensory
Motor: Association: |
|
|
Sensory:
|
Conducts impulses from skin or sense organs to nerve center.
|
|
|
Motor:
|
Conducts impulses from the nerve centers to muscles or glands.
|
|
|
Association:
|
Form connections between other neurons.
|
|
|
Cavities of the Body
|
Dorsal Cavity
Thoracic Cavity Abdominal Cavity Pelvic |
|
|
Dorsal Cavity –
|
brain and spinal cord
|
|
|
Thoracic Cavity –
|
Thorax – heart and lungs
|
|
|
Abdominal Cavity
|
= kidneys, digestive organs,
|
|
|
Pelvic –
|
end of digestive tract,
|
|
|
Peritoneum –
|
membrane that is in the abdominal cavity and pelvic cavity
|
|
|
CIRCULATORY SYSTEM
|
Carries gases, digested food and other materials to all parts of the body
|
|
|
MAJOR ORGANS
|
Heart
Arteries Veins |
|
|
DIGESTIVE SYSTEM
|
Takes in food, digests food, eliminates undigested wastes
|
|
|
DIGESTIVE SYSTEM
MAJOR ORGANS |
Mouth
Pharynx Esophagus Stomach(s) Small intestine Large intestine Accessory organs |
|
|
RESPIRATORY SYSTEM
|
Takes in air, uses certain gases from the air, expels waste gases.
|
|
|
RESPIRATORY SYSTEM
MAJOR ORGANS |
Lungs
Air passages |
|
|
MAJOR ORGANS
EXCRETORY SYSTEM |
Kidney
Bladder |
|
|
EXCRETORY SYSTEM
|
Eliminates wastes produced inside the cells.
|
|
|
NERVOUS SYSTEM
|
Collects information to regulate body functions.
|
|
|
NERVOUS SYSTEM MAJOR ORGANS
|
Brain
Spinal cord Nerves |
|
|
ENDOCRINE SYSTEM
|
Regulation of body chemical substances.
|
|
|
ENDOCRINE SYSTEM MAJOR ORGANS
|
Ductless glands
|
|
|
SKELETAL SYSTEM
|
Body framework, protects vital organs.
|
|
|
SKELETALSYSTEM MAJOR ORGANS
|
Bones
|
|
|
MUSCULAR SYSTEM
|
Allows body movement.
|
|
|
MAJOR ORGANS
MUSCULAR SYSTEM |
Muscles
|
|
|
REPRODUCTIVE SYSTEM
|
Produces sex cells.
|
|
|
REPRODUCTIVE SYSTEM MAJOR ORGANS
|
Ovaries
Testes |
|
|
Osteology –
|
Study of bones that make up the skeletal system
|
|
|
Skeleton
|
is the internal structure or framework of the body that is the basis for the external appearance
|
|
|
Bones are living structures that contain:
|
Blood and lymphatic vessels
Nerves They are subject to disease They undergo repair Adjust to stress, etc. |
|
|
1) Gives rigidity and form to the body
2) Provides protection (internal/vital organs) CNS by skull and vertebral column Heart and lungs by rib cage 3) Aids in locomotion by acting as levers Attachment to muscle 4) Stores minerals (Ca and P) Are deposited and withdrawn as needed 5) Forming the cellular elements of blood A function of the marrow within the cavity of the bone |
Functions of Bone
|
|
|
BONE –
|
composed of
organic framework of fibrous tissues and cells gives resiliency & flexibility reduces the danger of breakage forms the medium through which the bone derives most of its nourishment |
|
|
CARTILAGE
|
is a gristly flexible tissue
the majority of bone develops from cartilage is softer & more flexible & resilient than bone, but is less capable of regeneration once damaged |
|
|
hyaline cartilage -
|
most common
is a translucent, bluish-white substance usually found on the joint surfaces of moveable bones |
|
|
perichondrium -
|
thin membrane covering all cartilage
|
|
|
elastic cartilage & fibrocartilage
|
found in special locations in the body
|
|
|
red marrow
|
found in young animals
is a blood forming organ is soft & well-filled with vessels & cellular elements |
|
|
yellow marrow
|
more fatty & harder
does not perform blood forming functions is capable of reverting to red marrow in times of stress |
|
|
white marrow
|
mainly hard fatty tissue
nonfunctional for blood forming & cannot revert |
|
|
gelatinous marrow
|
found in aged animals
is a degraded semi-fluid form |
|
|
Medullary cavity (marrow cavity) –
|
space surrounded by the cortex of long bone
|
|
|
Older animals =
|
red is replaced by fatty yellow marrow
|
|
|
Young animals =
|
red marrow
|
|
|
Epiphysis –
|
refers to either end of the long bone
|
|
|
Proximal epiphysis =
|
closest to the body
|
|
|
Distal epiphysis =
|
farthest away from the body
|
|
|
Diaphysis –
|
cylindrical shaft of the long bone between the two epiphysis
|
|
|
Metaphysis –
|
the flared area adjacent to the epiphysis generally the widest part of the bone
|
|
|
Epiphyseal cartilage –
|
a layer of hyaline cartilage that separates the diaphysis and epiphysis within the metaphysis of an immature bone
|
|
|
Articular cartilage –
|
a thin layer of cartilage that covers the articular surface of the bone
|
|
|
Periosteum –
|
a fibrous membrane that covers the surface of a bone except where articular cartilage is located
|
|
|
Endosteum –
|
a fibrous membrane that lines the marrow cavity
|
|
|
Osteoblasts -
|
bone producing cells
|
|
|
Osteoclasts -
|
bone destroying cells
|
|
|
Classification of Bone
|
Types Long Short Flat Sesamoid Pneumatic Irregular
|
|
|
Long Bones
|
Consists of a relatively cylindrical shaft (diaphysis) & two extremities/ends (epiphysis
|
|
|
Short Bones
|
Are somewhat cuboid, or approximately equal in all dimensions
|
|
|
Flat Bones
|
Relatively thin and expanded in two dimensions
Consists of two plates of compact bone, lamina externa & lamina interna, separated by a spongy material |
|
|
Flat Bones
Main function |
is for protection of vital organs. Also function to provide large areas for muscle attachment (pelvic bones and scapulae)
|
|
|
Sesamoid Bones
|
Located along tendons to reduce friction, increase leverage, or change the direction (angle) of pull on tendons and muscles
|
|
|
Pneumatic Bones
|
Contain air spaces or sinuses that communicate with the exterior
|
|
|
Irregular Bones
|
Unpaired bones located on the median plane
Include the vertebrae and some of the unpaired bones of the skull Function in protection, support & muscle attachment |
|
|
The Axial Skeleton
|
Includes bones on or attached to the midline of the body
Comprises: Skull Vertebral column Ribs Sternum |
|
|
The Skull
|
Is a group of flat, irregular bones that shapes the head
It protects the brain and supports sense organs |
|
|
Cranial part (brain case) -
|
bones which surround the brain
|
|
|
Facial part –
|
remaining bones that are not part of the cranium
|
|
|
Lower Jaw -
|
Mandible
|
|
|
Upper Jaw” area –
|
Maxilla, Incisive bones
|
|
|
The Vertebral Column
|
Is composed of median (midline) unpaired irregular bones called vertebrae
Forms a column/chain of bones extending from the skull to the tail |
|
|
Common structure of vertebrae include
|
Body
Arch Processes |
|
|
Vertebral column is divided into 5 regions:
|
C cervical (neck region)
T thoracic (chest area) L lumbar (loin area) S sacral (pelvic area) Cd caudal or coccygeal (tail region) |
|
|
The Sternum & Ribs
|
Forms the floor of the bony thorax
Consists of individual bones called sternebrae that tend to fuse with advanced age Gives attachment to the costal cartilages of the ribs as well as forming a place of origin for the pectoral muscles |
|
|
Manubrium
|
(cranial extremity of sternum
|
|
|
Manubrium
Body Xiphoid process |
(cranial extremity of sternum)
(middle portion of sternum) (caudal extremity of sternum) |
|
|
Ribs
|
Form the lateral walls of the bony thorax
Located between the thoracic vertebrae & the sternum |
|
|
The Appendicular Skeleton
|
Is made up of the bones of the limbs
|
|
|
Pectoral limb
|
(thoracic limb or forelimb) girdle
|
|
|
Pelvic limb
|
(hind limb) girdle
|
|
|
Shoulder
|
Scapula
|
|
|
Brachium (arm)
|
Humerus
|
|
|
Antebrachium
|
Radius and ulna
(forearm) |
|
|
Carpus (knee)
|
Carpal bones
|
|
|
Metacarpus
|
Metacarpal bones
|
|
|
Digits
|
Phalanges (proximal middle, distal) Sesamoid bones (proximal and distal)
|
|
|
Pelvis
|
Pelvic bones (ilium, ischium, pubis)
|
|
|
Thigh
|
Femur
|
|
|
True leg
|
Tibia, fibula
|
|
|
Tarsus
|
Tarsal bones
|
|
|
Metatarsus
|
Metatarsal bones
|
|
|
Bone Formation
|
A local area of bone formation is referred to as a center of ossification
|
|
|
Types of Ossification
|
Endochondral (Intracartilaginous)
Intramembranous |
|
|
Endochondral Ossification
|
Develops from cartilage
|
|
|
Intramembranous Ossification
|
Develops from osteoid tissue within the bone itself
|
|
|
This bone turn over
|
remodeling
|
|
|
Through remodeling bone can:
|
Shrink (atrophy)
Increase in size (hypertrophy) Repair breaks Rearrange its structure in response to stress and strains (to resist stressors) |
|
|
Fracture -
|
a break in the continuity of a bone
|
|
|
Simple fracture
|
The skin over the fracture site is unbroken
|
|
|
Open (Compound) fracture
|
A wound from the exterior contacts the bone at the point of the fracture
|
|
|
Greenstick fracture
|
one side of the bone is broken or splintered & the other side is only bent
|
|
|
Complete fracture
|
the bone is broken entirely across
|
|
|
Physeal fracture
|
at the junction of the epiphysis and diaphysis of a bone
|
|
|
Comminuted fracture
|
One in which the bone was splintered or crushed producing small fragments
|
|
|
Osteomyelitis -
|
inflammation of the bone & bone marrow usually caused by bacteria (staphylococcus or streptococcus)
|
|
|
Bone tumors (Osteoma)
|
(slow growing, not likely to cause death)
Malignant (grow rapidly, metastasize and are often fatal if not treated) |
|
|
Rickets -
|
essentially a disease of young bones that chiefly affects the growing areas of bone
|
|
|
Osteomalacia
|
(adult rickets) - affects the entire bone
lack of vitamin D |
|
|
Osteology –
|
Study of bones that make up the skeletal system
|
|
|
Bones are living structures that contain:
Blood and lymphatic vessels Nerves . |
disease, repair, stress, etc
|
|
|
Functions of Bone
|
Gives rigidity and form to the body
Provides protection Aids in locomotion Stores minerals Forming the cellular elements of blood |
|
|
CARTILAGE
|
gristly flexible tissue
less capable of regeneration once damaged |
|
|
hyaline cartilage -
|
most common
is a translucent, bluish-white substance usually found on the joint surfaces of moveable bones |
|
|
elastic cartilage & fibrocartilage
|
found in special locations in the body
|
|
|
perichondrium -
|
thin membrane covering all cartilage
|
|
|
Compact (dense or cortical) bone –
|
hard layer that covers most bones and forms almost the entire shaft of long bone
|
|
|
Cancellous (spongy) bone –
|
composed of plates (spicules) arranged to form a porous network
|
|
|
Medullary cavity (marrow cavity) –
|
space surrounded by the cortex of long bone
|
|
|
Cell
|
A small microscopic mass of protoplasm bounded externally by a semi-permeable membrane which contains a nucleus
|
|
|
Vital Phenomena, 4 Basic Criteria
|
growth
reproduction irritability or excitability metabolism |
|
|
Hypertrophy –
|
increase in the size of a cell beyond it’s normal size (muscles with exercise)
|
|
|
Hyperplasia –
|
increase in size because of an increase in the number of cells
|
|
|
Atrophy –
|
decrease in size from normal
|
|
|
Aplasia –
|
failure of a tissue or organ to develop
|
|
|
Hypoplasia –
|
incomplete development of an organ
|
|
|
Reproduction
|
The ability to produce more cells or more organisms that are essentially the same as the original
|
|
|
Irritability (excitability)
|
The property of being able to react to a stimulus
|
|
|
Metabolism
|
Refers to physical and biochemical reactions occurring in each cell
|
|
|
Anabolic –
|
reactions that build and maintain cellular components
|
|
|
Catabolic –
|
reactions that breakdown cellular components
|
|
|
Homeostasis –
|
the tendency of living thing to attempt to maintain a state of relative stability
|
|
|
Absorption –
|
the process of taking dissolved materials or water through the cell membrane into the cell, occurs via diffusion, osmosis, endocytosis,
|
|
|
Secretion –
|
process of taking material produced by the cell and sending outside the cell, occurs via exocytosis
|
|
|
conductivity
|
transmission of stimuli to other cells by direct or indirect contact
|
|
|
contractility
|
critical property of muscle cells
|
|
|
organization
|
grouping of cells and tissues into organs and parts
and the integration of these parts into a functioning body |
|
|
intracellular fluid
|
Most body water is found within the cells
|
|
|
extracellular fluid
|
The remaining fluid is found outside the cells
|
|
|
Peptide
Polypeptide Protein |
less than 50 AA long
50 to 100 AA long over 100 AA long |
|
|
PROTEIN
Classified two ways structural: |
includes collagens (connective tissue), elastins (abdominal tunic), & keratins (hair, wool, horns)
|
|
|
PROTEIN
Classified two ways: reactive |
includes enzymes, protein hormones, histones, contractile proteins in muscle
|
|
|
Simple proteins –
|
only contain AA (e.g., albumins, globulins, histones
|
|
|
Conjugated proteins –
|
simple proteins combined with another component which is not a protein or an AA.
|
|
|
PROTEIN
Functions |
serve as structural elements
all enzymes are proteins makes up many hormones carriers, especially in the blood immunity -- antibodies transmission of genetic information |
|
|
Cellular Chemical Composition LIPIDS (Fatty Substances
|
Non-polar, Water insoluble (hydrophobic)
|
|
|
Lipids are found in:
|
vitamins (A, D, E and K)
hormones serve to store energy as body fat |
|
|
Four primary chemical types of lipids
|
Fatty Acids
Triglycerides Phospholipids Steroids |
|
|
Fatty Acids
|
Saturated
Unsaturated |
|
|
Triglycerides –
|
consists of a glycerol molecule with fatty acids attached
|
|
|
Phospholipids –
|
similar to triglycerides except a hydrophilic phosphate group has replaced one of the hydrophobic fatty acid groups
|
|
|
Steroids –
|
lipids in which the carbon atoms are connected in a ring
|
|
|
Monosaccharide
|
(simple sugars) contain three to seven carbon atoms
|
|
|
Disaccharide –
|
2 simple sugars combined
Sucrose (table sugar = glucose + fructose) |
|
|
Polysaccharide –
|
multiple glucose molecules linked together (e.g., Glycogen)
|
|
|
Electrolytes –
|
any molecular substance that in solution dissociates into its electrically charges components, called ions
|
|
|
5 Basic Components of the Cell
|
Cell membrane
Cytoplasm Nuclear membrane/envelope Nucleus Intracellular organelles |
|
|
CELL (PLASMA) MEMBRANE
|
Forms the outermost limits of the cell & separates it from other cells
|
|
|
Integral proteins
|
are firmly inserted into the cell membrane and may completely cross
|
|
|
Peripheral proteins
|
are mainly on the cytosolic surface of the membrane
They are often bound to integral proteins |
|
|
Transmembrane proteins
|
extend through the membrane (is a type of integral protein)
|
|
|
CELLULAR ORGANELLES GOLGI APPARATUS
|
Appears as a stack of flattened membranous sacs near the nucleus
|
|
|
ENDOPLASMIC RETICULUM
|
Membranous network found throughout the cytoplasm of the cell, in the form of tubules
|
|
|
MITOCHONDRIA
|
Powerhouse’ of the cell--supplies energy
|
|
|
MITOCHONDRIA
|
Formation of ATP for energy usage by any cellular activity that requires energy
|
|
|
Mitochondria
|
have their own DNA and RNA for reproduction purposes
|
|
|
LYSOSOMES
|
Membrane bound vesicles containing digestive enzymes (hydrolytic enzymes)
breakdown molecules by enzymatic action, reducing their size & composition |
|
|
NUCLEAR MEMBRANE/ENVELOPE
|
Forms a boundary around the nucleus and separates it from the cytoplasm
|
|
|
NUCLEUS
|
Contains the genetic material of the cell encoded in molecules of DNA
Usually located centrally within the cell |
|
|
NUCLEUS
Primary functions |
Regulate protein synthesis
Regulate the biological activities of the cell Ensure the passage of genetic material to subsequent generations of cells/organisms |
|
|
muscular system is the most prominent and extensive anatomical feature of the body
Divided into three major types depending on their cellular structure |
skeletal
smooth cardiac |
|
|
The bulk of the muscle in the body is
|
skeletal
|
|
|
Skeletal Muscle
|
The muscle cells (fibers) of skeletal muscle are grouped into distinct organs of variable size called muscles
|
|
|
Skeletal Muscle
|
attached to bones of the skeleton /voluntary control
A.k.a. striated muscle |
|
|
A.k.a. striated muscle
|
microscopic fibers appear striped due to the orderly arrangement of contractile proteins
|
|
|
Smooth Muscle
|
Involuntary or unstriated muscle
no microscopic striations visible |
|
|
Smooth Muscle
Systems with autonomic function |
The digestive tract, urogenital tract, Blood vessels
|
|
|
Smooth Muscle
Contraction is an intrinsic property of the fibers themselves |
Contraction does not require stimulation by a nerve
However contractility is regulated and coordinated by the ANS |
|
|
Cardiac Muscle
|
visible striations
It is a type of striated muscle |
|
|
Cardiac Muscle
|
Actions is like smooth muscle, cardiac muscle contracts intrinsically (not under voluntary control)
|
|
|
Cardiac Muscle
Restricted to the heart – constitutes most of the thickness of the wall |
constitutes most of the thickness of the wall
|
|
|
Cariac Muscle
|
Rhythmic contractions are responsible for circulation of blood
|
|
|
Functions of the muscular system
|
are all based on contraction (shortening) of muscle fibers
|
|
|
Examples of smooth muscle contract to:
|
Mix and propel food along the GI tract
Control blood distribution in the body Adjust the diameter of the pupil and lens In skin – causes hair to stand up |
|
|
Example of Skeletal Muscle:
locomotion by contracting muscles and moving joints respiration move air in and out of lungs heat production by shivering |
locomotion by contracting muscles and moving joints
respiration move air in and out of lungs heat production by shivering |
|
|
Skeletal muscles permit locomotion by:
Contracting to change positions of bones Maintaining joint angles against the pull of gravity Gravity = movement ex: flexion of head |
Contracting to change positions of bones
Maintaining joint angles against the pull of gravity Gravity = movement ex: flexion of head |
|
|
Skeletal muscles are involved in heat production through shivering
Shivering - brief repetitive contractions of skeletal muscle throughout the body |
brief repetitive contractions of skeletal muscle throughout the body
|
|
|
Muscle fibers (cells) are arranged in bundles surrounded by fibrous connective tissue
|
Endomysium
Perimysium Epimysium |
|
|
How are muscles classified?
|
By control: Voluntary-animal controls/all striated.
B. By appearance: Smooth or striated C. Function |
|
|
How are muscles named?
|
A. Action
B. Attachments C. Shape D. Position E. Direction F. Function G. Kind |
|
|
How are muscles arranged?
|
Sheets
Bundles - Spindle shaped - legs Feather – internal organs, reproductive organs in a female |
|
|
Why do muscle fibers vary in length and size?
|
A. Length of muscle they are apart of.
B. Males generally have longer fibers. C. Animals on full feed have larger fibers than animals on restricted feeds. D. Exercise can increase muscles in volume. |
|
|
Parallel arrangement of muscle fibers
Can be arranged in: |
parallel sheets
bands |
|
|
parallel sheets -
|
the abdominal muscles
|
|
|
bands -
|
sartorius muscle on the medial side of the thigh
|
|
|
Fusiform arrangement of muscle fibers
|
Spindle shaped
Tapered at both ends |
|
|
Penniform (feather-like) arrangement
|
In this arrangement a tendon represents the quill and the muscle fibers attaching to the tendon at an angle represent the vane of the feather
|
|
|
Three types of penniform arrangements
|
Unipennate
Bipennate Multipennate |
|
|
Unipennate
|
fibers come from only one side
|
|
|
Bipennate
|
fibers come from both sides
|
|
|
Multipennate
|
fibers come from three or more sides
|
|
|
Fleshy attachment
|
Appears to arise directly from the bone
It is actually attached to the bone (periosteum) by very short tendons |
|
|
Tendon attachment
|
Fibrous bands of collagen connecting muscle to bone
Composed of dense connective tissue in parallel bundles Most tendons are cords or bands that attach spindle-shaped or pennate muscles to bone |
|
|
Aponeuroses -
|
flat sheets of tendons
|
|
|
Origin –
|
less moveable attachment (usually proximal)
|
|
|
Insertion –
|
more moveable attachment (usually distal)
|
|
|
Flexor –
|
is a muscle on the side of the limb toward which the joint bends – decreases angle of 2 bones
|
|
|
Extensor –
|
muscle on the opposite side of the flexor – increases angle of 2 bones
|
|
|
Adductor -
|
muscles that tend to pull the limb toward the median plane
|
|
|
Abductor -
|
muscles that tend to move the limb away from the median plane
|
|
|
Sphincter muscles –
|
are muscles that surround an opening (striated or smooth)
|
|
|
Striated: e.g., orbicularis oculi -
|
striated muscle in the eyelids - its contraction closes the eyelids
|
|
|
Smooth: e.g., pyloric sphincter –
|
smooth muscle that surrounds the opening between the stomach and the small intestine that controls the passage of food
|
|
|
Classification of muscles according to the part each plays in movement or action
|
Agonist
Antagonist |
|
|
Agonist
|
Prime movers
The muscles directly responsible for producing the desired action |
|
|
Antagonist
|
The muscles that oppose the desired action
Have an action directly opposite that of the agonist |
|
|
If the desired action is extension of the elbow
Agonist – Antagonist – |
triceps brachii (extensor of the elbow)
biceps brachii (flexion the elbow) |
|
|
If the desired action is flexion of the elbow (instead of extension)
Agonist – Antagonist - |
biceps brachii
triceps brachii |
|
|
Synovial Structures
|
Joint Capsules
Bursa (Bursae) Synovial Sheaths |
|
|
Bursa –
|
synovial sac between two structures that rub against each other
Gives protection in little spaces Inflammation = bursitis (capped hock, capped elbow) Poll evil and fistulous withers |
|
|
Synovial sheath –
|
gives protection for longer distances between bones
Inflammation = wind puffs and thoroughpin |
|
|
Thoracic limb
|
Act on the shoulder, elbow, carpus, digits
|
|
|
Pelvic limb
|
Act on the hip, stifle, hock (tarsus), digit
|
|
|
Head
|
Act on mastication, facial expression
|
|
|
Trunk and neck
|
Vertebral column, abdominal function, respiration
|
|
|
Abdominal Muscles
|
Support the organs of the digestive and reproductive systems, also used in regurgitation and forced expiration
|
|
|
The front limb:
Trapezius: |
head to lumbar vertebrae
|
|
|
The front limb:
Serratus Ventralis |
fan shaped muscle from cervical vertebrae to scapula.
|
|
|
The front limb:
Brachiocephalicus |
main extensor of the shoulder
|
|
|
The front limb:
Latissimus dorsi: |
flexor of the shoulder
|
|
|
The front limb:
Pectorals: |
primary muscle in the brisket
|
|
|
The front limb:
Biceps: |
flexor of the elbow
|
|
|
The front limb:
Triceps: |
extensor of the elbow
|
|
|
Hamstring muscles
|
main extensors of the hip(I.e. the biceps, femurs, ect.)
|
|
|
Longissumus dorsi
|
extend along either side of the vertebrae, responsible for extension and lateral flexion of the spinal column.(The may even twist the spinal column.I.e. bucking bull)
|
|
|
sternocephalicus
|
is a flexor of the head.
|
|
|
Abdominal muscles, they aid in…..
|
1. Defecation
2. Urination 3. Parturition 4. Regurgitation 5. Respiration |
|
|
Skeletal Muscle Fiber
|
actually a long, multinucleated cell with visible striations
|
|
|
Sarcolemma
|
is the outer cell membrane
connects the muscle fiber to the tendinous part of the muscle/tendon |
|
|
Nuclei
|
are numerous
located beneath the sarcolemma |
|
|
Slow twitch fibers (type I fibers)
|
Contract slowly but can contract for long periods
Mainly found in muscles which perform sustained & continuous work (antigravity muscles |
|
|
Fast twitch fibers (type II fibers)
|
Contraction is fast
Mainly found in muscles which perform quick “bursts”, but intermittent movement |
|
|
Slow and Fast twitch fibers stain differently
|
Slow – light
Fast - dark |
|
|
The difference in color for fast & slow meat is related to
|
Their relative density
The number of mitochondria in the muscle cytoplasm (sarcoplasm) |
|
|
Excitation
|
Skeletal muscle contraction is triggered by the generation of an action potential (AP) on the sarcolemma
|
|
|
An AP is initiated
|
by firing of a motor neuron whose axon terminates at the neuromuscular junction
|
|
|
end-plate potential
|
Local depolarization of the sarcolemma at the neuromuscular junction
|
|
|
Acetylcholinesterase (enzyme) quickly degrades
|
Ach, so Ach has only a momentary effect
|
|
|
Myofibril is made up of:
|
myosin (thick) filaments
actin (thin) filaments |
|
|
Myofibril
filaments form bands |
I – band
A - band |
|
|
I-band
|
are light colored
contains only actin (thin) filaments |
|
|
A-band
|
dark colored
where actin and myosin (thin and thick filaments) overlap |
|
|
Tetanus =
|
stimulation of contraction is so rapid that the muscle turns into a consistent state of contraction.
|
|
|
Fatigue =
|
can be one fiber or entire fibers muscle – decrease in the availability of ATP – lead to lactic acid build up because the Ph is reduced/ Pain soreness of muscle
|
|
|
A dense line (called a Z line)
|
bisects each I band
|
|
|
sarcomere
|
The segment of myofibril between each Z line
|
|
|
Sarcomere
|
is the fundamental unit of contraction of striated muscle
|
|
|
Relaxation
|
Contraction continues as long as there are Ca ions present in the sarcoplasm
|
|
|
Contraction of Smooth Muscle
|
Innervation is automatic
|
|
|
Contraction of Smooth Muscle
Will respond to either: |
norepinephrine (released by the sympathetic nerves)
acetylcholine (released by the parasympathetic nerves) |
|
|
Cardiac Muscle
Force and rate of contraction are regulated by |
the autonomic nervous system
certain reflexes & hormones exogenous chemicals concentration of sodium, potassium, & calcium ions in the blood plasma & interstitial fluid |
|
|
Sino-atrial (S-A)
|
node
‘pacemaker’ of the heart is where contraction impulses for a normal heartbeat originate inherent capability to contract rhythmically |
|
|
Hypertrophy
|
is an increase in cell size
occurs when the heart has excessive work to do in man, called athlete’s heart can be caused by living in high altitude |
