Lesson 8: Skeletal, Nervous + Muscular Systems Flashcards
What are the 4 types of bones?
Long, short, flat and irregular.
What is a long bone?
Long bones are longer than their width.
What is an example of a long bone?
Femur / tibia
What is a short bone?
Short bones are similar sizes in length and width.
What is an example of a short bone?
Carpals / tarpals
What is a flat bone?
Flat bones are thin and usually curved.
What is an example of a flat bone?
Ribs / sternum
What is an irregular bone?
Irregular bones are ones that don’t fit into the categories of long / short or flat bones.
What is an example of an irregular bone?
Hips / vertebrae
Why are cortical bones essential?
They provide strength as they are the tendon attachment sites for muscles as well as for organ protection.
What is the structure of a cortical bone similar to?
Honeycomb
What do trabecular bones provide a large surface for?
Mineral exchange.
What do trabecular bones do alongside providing large surface area for mineral exchange?
Maintain skeletal strength and integrity.
What is the structure of trabecular bones like?
Spongey
What are areas that contain a lot of trabecular bones more prone to?
Osteoporosis
What are epiphyses?
The two ends of diaphysis.
What is the diaphysis in a bone?
The ‘shaft’ or middle part that forms the bone.
What is the medullary cavity in a bone?
The hollow bit inside diaphysis that is also called the yellow bone marrow cavity.
What is the endosteum in a bone?
The thin connective tissue layer.
What is the periosteum in a bone?
The dense connective tissue that is supplied with nerves and blood cells.
What are the diaphysis and outer layers of epiphyses composed of?
Cortical bone
What are the central regions of epiphyses composed of?
Trabecular bone
Some long bones contain red marrow, what is this essential for?
The manufacturing and maturation of red blood cells, white blood cells and platelets.
What is the epiphyseal cartilage?
The ‘growth plate’ that seperate the diaphysis and epiphysis in children/young adults to allow for bone growth.
What is proprioception?
Proprioception is the sense of knowing where the body is in relation to various segments and the external environment.
How does proprioception work?
Sensory information is gathered via receptors in the skin, inner ears, in/around joints and muscles.
What do the cutaneous receptors send sensory information (for proprioception) about?
The cutaneous receptors are skin receptors. They gather information regarding pressure, touch and movement of skin hairs.
What do joint receptors send information (for proprioception) about?
They send information regarding positions, velocity and accelerations occuring at joints.
Where are the joint receptors located?
In the joint capsules and surrounding ligaments.
What do pressure receptors send information (for proprioception) about?
They add further information regarding pressure changes that is important for postural adjustments and normal gait.
What are Pacinian Corpuscles?
Receptors deep in the skin and joint capsules that are sensitive to pressure.
What are Meissner’s Corpuscles?
Receptors located in the superficial layers of the skin that respond to light touch.
What external forces are placed on a muscle fiber in order for it to lengthen?
Gravity, momentum, antagonistic muscle contraction and force applied via someone else.
What should the sarcomere do when stretching effectively (and without injury)?
The sarcomere should lengthen to a point where it overlaps filaments with at least X1 Cross-Bridge between the actin and myosin.
What does aging inevitably cause a decrease in (muscle wise)?
Muscle function, strength, endurance, agility and flexibility.
How would the effects of aging worsen?
If the individual is inactive, has a disease or is injured.
Why does muscle essentially decline with age?
This is due to atrophy AKA the wasting away of muscle.
What does muscle atrophy cause/do?
Muscle atrophy causes decreases in muscle size and number of fibers as well as the water component. The muscle fibers are replaced with collagen which causes the muscles to essentially stiffen up and decrease mobility.
What does resistance training enhance in tendons and ligaments?
Tensile strength of tendons and ligaments.
What does stretching maintain for tendons/ligaments and muscles? And what does it allow for joints?
Maintains suppleness/flexibility and allows full ROM at joints.
Why are women generally more flexible than men?
Men and women have both anatomical and physiological differences that give women more room for flexibility.
Examples are wider hips in women, heavier and rougher pelvic bones in men, women having shorter legs.
Why might a fractured elbow have reduced functionality?
A fractured elbow will have excess calcium in the joint space which will cause the reduction in movement.
How might skin affect a joint’s movement?
If there has been a recent injury or surgery where there is a laceration/tear/incision then the skin tissue will become inelastic and incapable of stretching at the joint.
Why does a higher intramuscular temperature affect the effectiveness of stretching a muscle? (3)
By increasing the intramuscular temperature:
- The muscle’s collagen ability will enhance
- Elastin components within musculotendinous units will deform
- The Golgi-tendon Organ’s will reflexively relax through autogenic inhibition.
What is the optimal temperaute for a muscle to achieve effective stretching?
103 degree F (39 degree C)
What does cooling down post-exercises all the body to do? (5)
- Cool down core temperature
- Muscular relaxation
- Promote removal of waste products via blood
- Reduce muscular pain/soreness
- Adjust cardiovascular system back to normal
When is muscle temperatures at their highest?
Immediatly post-exercise.
What are some physiological functions that exhibit circadian rhythms and max/min functions at specific times throughout the day? (6)
Blood Pressure Body Temperature Heart Rate Hormone Levels Alertness Responsiveness Oscillate (Movement Back/Forth)
Why could height differ throughout the day?
The vertbral column/spine may become shorter during the day due to fluctuating fluid levels surrounding its intervertebral disks. In day time, the spine is vertical and therefore subject to dynamic muscular forces, gravitional forces of body weight and hydrostatic pressure. This causes the vertebrae’s surroundings to narrow as fluid is squeezed out of the disks.
Since the spine is horizontal at night, the disks can reabsorb fluids from the surrounding areas and renew it’s usual body length.
What implications does the increased hydration and subsequent swelling (of disks) upon waking have on the spine?
- Increased stiffness during lumbar flexion (bending forward.)
- Lumbar disks/ligaments having greater risk of injury.
- Lower ROM in the AM compared to later on.
Why should a programme focused on increasing flexibility be performed later in the day?
There is more risk of injury in the morning due to the temporary swelling (of increased disk hydration) from sleeping as well as limited ROM.
What is the epiphyseal line?
When growing is complete and the epiphyseal cartilage is replaced by a bone aka the epiphyseal line.
What is the periosteum?
A dense connective tissue layer that covers the outer surface of the bone.
What is remodelling?
The continual reshaping/rebuilding of the skeleton in response to internal/external signals from specialized bone cells.
What can remodelling do?
It can either build bone (osteoblasts) or break it down (osteoclasts.)
What are the reasons for remodelling?
- To repair damage to the skeleton that can results from repeated stress.
- To prevent accumulation of old bone.
- To remove calcium/phosphorus from the bones when these minerals are deficient in diet.
What does Wolff’s law indicate?
That changes in bone structure coincide with changes in bone function. For example, when the skeleton is subject to stressful forces, it responds by laying down more bone tissue, thus increasing the bone density.
What happens when you experience prolonged amounts of bed rest?
Your bones lose minerals and density.
What are the most important functions of the axial skeleton? (3)
- Protect the Central Nervous System
- Provide main axial body support
- Protect the organs of the thorax