1 - Muscular anatomy Flashcards
How many bones are in the human body
206
The functions of the skeleton
- Protection of vital organs
- Support and maintenance of posture
- Providing attachments points for muscles
- Storage and release of minerals (calcium and phosphorus)
- Blood cell production
- Storage and energy
Dynamic tissue
tissue that is constantly changing in response to activity levels
What is Wolffs law
Muscle will adapt to the pressure placed on it
Name the two types of skeleton, their purpose and what bones they include
- Axial skeletion
Purpose: To provide protection
Made up of:
- Skulls
- Sternum
- Ribs
- Vertical column
- Appendicular skeleton
Purpose: To produce movement
Made up of:
- Pectoral girdle (clavicle and scapula)
- Humerus
- Radius
- Ulna
- Carpals / Metacarpals / phalanges
- Pelvic girdle
- Femur
- Patella
- Tibia
- Fibula
- Tarsals / Metatarsals / phalanges
Describe the structure of the vertebrae column and each parts functions
Cervical - Are the smallest and have more movement than the thoracic and lumbar
Thoratic - Are less mobile as the ribs attach to the sides of each vertebra and therefore restrict movement
Lumbar - Are the biggest and strongest as they play a major role in weight bearing and therefore absorb high compression loads
Sarcal - transmit weight from the pelvis to the legs
Coccyx
Types of bones
- Short - Small cubed shaped and are for stability and movement
- Long - Important for movement
- Flat - Provide protection and large surface areas for joints to hold onto
- Irregular - Have specialized shapes for specific functions
The structure of a long bone
- Epiphysis
- Diaphysis
- Epiphysis
- Articular cartilage
- Spongy bone
- Space containing bone marrow
- Compact bone
- Medullary cavity / marrow cavity
- Bone marrow
- Periosteum
- Nutrient foreman
Epiphysis
Are the ends of the bone made from spongy bone
Diaphysis
made up of compact bone and is solid and dense. Found in the outer layer of most bones. Important for protection and support and resists the stress being placed on long bones.
Articular cartilage
covers the end of the bone where they articulate with other bones to form joints. Main function of cartilage is to reduce friction between bones by absorbing shock.
Periosteum
Covers areas that are NOT covered in cartilage, forming outer lining of bone.
Periosteum is important for:
⎫ Growth
⎫ Repair
⎫ Nutrition
⎫ Attachment of ligaments and tendons
Medullary (marrow) cavity
is the space within the diaphysis where the yellow bone marrow is stored.
Nutrient foramen
Small opening in the diaphysis. Blood vessels pass through here, enter the medulla cavity and provide the bone marrow and compact bone with blood and nutrients.
Location of bones using anatomical terminology
1) Inferior - Below or further away from the head
2) Superior - Above or nearer to the head
3) Distal - Further away from where a limb attaches to the body
4) Proximal - Nearer to where the limb attaches to the body
5) Posterior – Behind or nearer to the back
6) Anterior – In front or nearer to the front
7)
Internal – Located inside of further away from the surface
8) External – Located on or near the surface
9) Lateral – Further away from the midline of the body
10) Medial – Closer to the midline of the body
Functions of connective tissue:
- Supporting and binding
- Protecting
- Insulating
- Storing reserve fuel
- Transporting substances around the body
Joint
Where two or more bones articulate with each other
Main function: Increase mobility of the body
Ligament
the connective tissue attaching bone to bone
Tendon
Muscle to bone
Joint stability is determined by…
- Joint movement
- Shape of the bones and whether they interlock or not
- Flexibility of ligaments
- Influence of other soft tissue structures
The different types of joints
1) Fibrous
• Fixed / immovable
2) Cartilaginous
- Semi-movable
- Bones are separated by cartilage
3) Synovial
- Freely movable
- Most important for mobility
- Most common
Label a synovial joint
Articular cartilage Synovial membrane Synovial fluid Bursea Meniscus Ligament Articular capsule
Meniscus
a piece of cartilage that provides a cushion between the femur and tibia. It can be damaged or torn under pressure.
Joint cavity
the space between the bones, contains synovial fluid
Articular cartilage
Smooth white layer that cover articulating surfaces of bones. Reduces friction, adsorbs shock and protects the bones.
Synovial membrane
Lines the capsule that secretes synovial fluid. Lubricates joint cavity, reduces friction and provides nutrients to cartilage.
Bursae
Small fluid sacs found where two structures rub against each other. Provide lubrication.
The types of synovial joints
- Gliding joints
- Least amount of movement
- Glide back and forth or slide to slide
- Found between tarsal and carpal bones - Hinge joints
- Bend or straighten in ONE direction
- Bones usually fit into each other, convex and concave
- Found in the knee or elbow - Pivot joint
- One bone forms a ring and the other rolls around it.
- Found in the radius and ulna - Condyloid joint
- Oval or egg shaped convex surface fits into a reciprocally shaped concave surface
- Radius and carpal bones - Saddle joint
- Saddle shaped bone fits against another bone shaped like the legs of the rider.
- Between carpals and metacarpals - Ball and socket joint
- Sphere shaped head of one bone fits into a rounded cavity on the other bone.
- Shoulder joint
Characteristics of general muscle tissue
Contractibility – able to contract
Extensibility – able to extent or stretch Elasticity – Resumes normal shape after being stretched Atrophy – Reduction in size of cell Hypertrophy – Increase and growth in cell Controlled by nerve stimuli and fed by capillaries
Types of muscle
1) Skeletal muscle • Voluntary control • Strained appearance (alternating dark and light bands) • Tendons that attach mostly to bones • Main function: to move the skeleton
2) Cardiac muscle
• Involuntary control
• Strained appearance
3) Smooth muscle
• Involuntary control
• Not strained appearance
• Lines walls of blood vessels and organs
Voluntary control
Have to think about it then the muscle does it
Involuntary control
No conscious thought needed for the muscle to do it
Striated
appearance of light and dark stripes.
Functions of muscles:
- When skeletal muscles contract they exert force on tendons which then pull on the bones causing movement
- Muscles can move substances within the body. Muscles pump blood to all the tissues / food / help blood return to the heart.
- Stabilize and maintain body positions.
- Generate 85% of body heat.
Skeletal muscle annotated
- Epimysium
- Perimysium
- Endomysium
- Muscle fibre
- Myofibril
- Sacromere
- Actin
- Myosin
Myofibril
A basic rod like unit of a muscle cell. They are made from repeated sections of sarcomeres which appear striated
Sarcomere
Basic contractile unit of a muscle fiber. It is made from two main proteins – action and myosin- they are responsible for muscular contraction
Label a sarcomere
- I band
- H zone
- Actin
- A band
- M line
- Myosin
- Z line
Fascia
Type of connective tissue located in or around bones and muscles, Made up of fibrous tissue, adipose (fatty) tissue and fluid
There are three layers of fascia in each skeletal muscle:
Epimysium - outer layer that covers the entire muscle
Perimysium - surrounds bundles of muscle fibers
Endomysium - layer of fascia that surrounds the individual muscle fibers.
What happens to the muscles when they exercise
Increased activity = hypertrophy due to increased number of myofibrils
When someone doesn’t exercise the number of myofibrils decrease and it will waste away or atrophy.
Hypertrophy - Increase in muscular size due to exercise
Why muscles preform well
♣ Muscles have a good blood and nerve supply unlike ligaments and tendons.
♣ Rich network of capillaries which provide muscles with oxygen, nutrients, calcium and remove waste. This means muscles are good at repairing damage.
- Nerves that bring the impulses from the CNS to the muscles are called motor neurons.
- The neurons release neurotransmitters into the blood to stimulate muscle contraction+ force.
Origin
Attachment of a muscle tendon to a stationary bone. Doesn’t move during contraction
Insertion
Attachment of muscle tendon to a movable bone. Moves during contraction.
Name and label muscles in the anterior
- deltoid
- Pectorials
- iliopsoas
- sartorius
- quadriceps
- femoris (rectus femoris, vastus intermedialis, vastus medialis, vastus lateralis)
- tibialis anterior
- abdominus rectus
- external obliques
- biceps brachii
Name and label muscles in the anterior
- trapezius
- triceps brachii
latissimus dorsi - gluteus maximus
- hamstrings ( biceps femoris, semitendinosus, semimembranosus)
- gastrocnemius
- soleus
- erector spinae
