what are the 5 functions of the skeleton?
support, protection, muscle attatchment, mineral storage, blood cell formation,
How do bones and muscles work together in a lever system to allow movement?
bones provide a system of levers on which muscles act to produce movement
What are the principal minerals that are stored in bones and help strengthen bone?
phosphorus and calcium
spongy bone
lightweight, endures force/pressure
bone marrow
red: makes blood cells, yellow: stores fat
compact bone
made of osteon systems, contains haversian canals
periosteum
a tough layer of connective tissue
haversian canal
network of tubes that contain blood vessels and nerves
osteocytes
mature bone cells
osteoclasts
clean up bone (release enzymes that digest bone)
osteoblasts
build bone (help deposit minerals)
yellow marrow
stores fat
red marrow
produces blood cells
ossification
when cartilage is replaced by bone during the process of bone formation
which types of bone cells are involved with ossification?
osteoblsts
ball and socket joint
circular motion, ex. shoulder/hip
hinge joint
back and forth,ex. knee and elbow
pivot
twisting/rotating, ex. neck
what purpose does cartilage serve in joints?
it protects the surfaces of the bones
ligaments connect...
bone to bone
Skeletal muscle: where can it be found? whats its function? is it striated or not? is it voluntary or involuntary?
attatches to bones, responsible for voluntary movement, striated, voluntary
Smooth muscle: where can it be found? whats its function? is it striated or not? is it voluntary or involuntary?
walls of hollow structures. move food through digestive track, control the way blood flows through circulatory system, decreases the size of your pupils in bright light. not striated. involuntary.
Cardiac muscle: where can it be found? whats its function? is it striated or not? is it voluntary or involuntary?
the heart. control heart. striated. involuntary.
myosin filament
a protein in the thick filaments, stationary
actin filament
a protein in the thin filaments, slides
how does a muscle contract?
the thin filaments (actin) in the muscle fiber slide over the thick filaments (myosin)
which filament slides?
actin
which filament remains stationary?
myosin
is there a change in filament length?
no
which molecule supplies the energy for muscle contraction?
ATP
which molecule allows myosin and actin to interact?
calcium
In terms of the contraction and the number of muscle fibers...whats the difference between picking up a piece f paper and picking up a book?
the number of muscle fibers used. heavier = more muscle fibers, lighter = less muscle fibers
If muscles contract and bones don't, how is it when we bend our knee the bones of the lower leg move?
the tendons pull the bones to make them work
what are the different functions of the skin?
protection, regulates body temperature, removes waste products, barrier against infection, prevents injury
how do the skin and the nervous system interact?
contains sensory receptors that transmit to the nervous system
what's the best way to protect skin against UV radiation and aging?
apply sunscreen, wear sunglasses and a hat,
how many bones are in an adult skeleton?
206
ligament
connective tissue that attaches bone to bone
tendon
connective tissue that attaches muscle to bone
joint
anywhere 2 bones meet
which joints are immovable?
joints in the skull
which joints are movable?
ball and socket, hinge, and pivot
how many muscles are in the body?
over 600
what action do muscles make?
contractions (to get shorter)
striated
striped in appearance
voluntary
under conscious control
sarcomere
contracting unit of muscle
what allows the myosin head to attach to actin and pull?
calcium allows them to attach
what is the end result of muscle contraction?
sarcomere unit is temporarily shortened.