support and movement Flashcards
Are hollow or solid tubes more structurally sound?
hollow
What structures are involved in basic stem morphology?
epidermis, vascular bundle, pith, cortex
What tissue is the pith made of?
parenchyma
What are the cell walls of the pith like?
thin
What tissue is the cortex made of?
collenchyma
What are the walls of the cortex like?
primary wall with some thickening in the corners
What is the vascular bundle surrounded by?
sclerenchyma
What wall surrounds the vascular bundle?
thick secondary cell wall
What is the purpose of the primary root (tap root)?
anchorage and stability
What is the purpose of the lateral roots?
absorption of water and dissolved minerals
What is the hydrostatic skeleton?
capsule of fluid surrounded by two layers of muscle
What are the two layers of muscle in the hydrostatic skeleton?
circular and longitudinal
What do the circular muscles do when they contract?
elongate and narrow the body
What do the longitudinal muscles do when they contract?
shorten and thicken the body
What is an exoskeleton do?
hard outer surface is for protection of the soft tissues
What are some features of the exoskeleton?
strong and light, mineralisation, thin and flexible at joints
What are limitations of the exoskeleton?
can be crushed, does not grow in line with the body
What are the two types of endoskeleton?
cartilaginous and bony
What does the bony endoskeleton do?
support the weight of large animals on land - rigid support against gravity
What are osteons?
cylindrical vascular tubes formed by osteoclast rich tissues
What are the functions of the skeletal system?
provides support, determines the shape of the body, protection of vital organs
What is the skeletal system a mineral store for?
calcium and phosphates
What bone marrow does the skeletal system contain?
red bone marrow
What is the function of short bones?
support and stability - limited movement
What is the function of long bones?
limbs; levels; transmit longitudinal forces
What is the function of flat bones?
protective, muscle attachments
What are the three parts of a long bone?
epiphysis, diaphysis, metaphysis
What is in the medullary cavity?
adipose tissue
What are the two membranes in a long bone?
periosteum and endosteum
What is Wolff’s law?
bones will adapt to the degree of mechanical loading
What are the two components of the bone matrix?
inorganic = 67% and organic = 33%
What makes up the inorganic component?
hydroxyapatite
What makes up the organic component?
collagen and other proteins
How many bones are there in the body?
206
What are the two skeletons?
axial and appendicular
What is part of the axial skeleton?
skull, vertebral column, ribs, sternum
What is part of the axial skeleton?
skull, vertebral column, ribs, sternum
What is part of the appendicular skeleton?
limbs
What are the types of vertebral columns?
cervical (7), thoracic (12), lumbar (5)
What are the types of ribs and how many of each?
7 true, 5 false (2 floating)
What are the types of joint?
cartilaginous and synovial
What are the three principle functions of skeletal muscle?
movement of the body, posture and heat production
What is digastric?
two muscle bellies connected by a tendon
What is 1st class lever system?
muscle attachment to bone relative to joint
What is most common type of level system?
3rd class
What are the components of muscles?
contractile cells and connective tissues
What are the muscle shapes?
circular, parallel, pennate, convergent
What is the function of a tendon?
transfer the force of muscle pull to bone to facilitate joint movement
What are the two specialised regions for attachment to the muscoskeletal system?
myotendinous junction, osteotendinous junction
What is isotonic contraction?
change in the length of the muscle
What are the two types of isotonic contraction?
concentric, eccentric
What is concentric contraction?
muscle gets shorter
What is eccentric contraction?
muscle gets longer
What is isometric contraction?
muscle contracts but stays the same length
What is the role of the cortex in control of movement?
plans voluntary movement
What is the role of the basal ganglia in control of movement?
enhances desired movements and inihibits unwanted movements
What is the role of the thalamus in control of movement?
relays sensory information to cerebral cortex
What is the role of the brain stem in control of movement?
conveys sensory information to cortex and motor informations to motor neurones
What is the role of the cerebellum in control of movement?
coordinates motor output
What happens in the knee jerk reflex?
Stimulate patellar tendon
Activates stretch receptors or muscle spindles within the extensor muscle
Activates sensory nerve
Extensor muscle contracts
Flexor muscle relaxes