Exam 3 Bio Flashcards
how many bones in the body
206
what is bones primary purpose
structure and protection
what is the difference between compact and spongy bones
spongy - very porous
compact - hard and non-porous
what are the three types of cartilages and characteristics
- hyaline - commonest, trachea
- fibrous - discs between vertebrae
- elastic - flexible, ear lobe
what are the five joints
- ball and socket into concave sic - hip and shoulder
- hinge - spool-shaped - elbow, knee
- pivot - rotation movement atlas - axis
- fibrous - between skull bones (suture)
- cartilaginous - between vertebral disc
what does ossification mean
gradual hardening of bones
is bone a living tissue
yes, it is constantly growing
can you tell the sex and approximate age from skeletal remains
yes
sex by the pelvic bones will be wider for women
age by shape and tissue
what is the purpose of the atlas and the axis
atlas rotates on axis
What are the functions and characteristics of the skin?
Functions: senses, waterproof, protection
Characteristics: weighs about 6 pounds, elastic, waterproof
is the skin a non-selective or selective excretory organ?
non-selective
how does the skin aid in body temperature?
Vasoconstriction: cold shrink
Vasodilation: heat spread/stretch
know the characteristics of the epidermis and dermis
epidermis: outer layer, five layers, keratinization(flattening cells)
dermis: inner layer, vessels, glands and nerves, fingerprints
What are melanocytes?
cells in pigmentation
what are chromatophores
holds color or dye (tattoos)
which layer of skin does mitosis occur?
epidermis
what is keratinization?
the flattening and drying of cells closer to the outer layer of the skin
what is the role of eliedin in the keratinization process
to be a protective skin oil
what does ‘epidermal derivative’ mean as it relates to nails and hair
they continue to grow
what is the difference between determinant and indeterminant hair?
determinant: grows to certain length then stops(body hair)
indeterminant: grows indefinitely (hair on head)
what are the three types of nerve endings and what do they sense?
- Bare/naked - sense pain, and temperature
- Meisserners corpuscles - deep touch
- Pacinian corpuscles - pressure receptors
What is the difference between first, second and third degree burns?
- First degree: epidermis only, death if over 2/3 of body
- second degree: into but not through the dermis
- Third degree: epidermis and dermis destroyed, into underlying tissue
what are the two dangers burn victims face?
- loss of water - plasma protein
- bacteria infection and loss of blood circulation
What is the difference between somatic and autonomic nerve tracts?
Somatic: away from skin, receives signals from skin and passes them to CNS
Autonomic: to skin, from CNS to the skin
What is the difference between Holocrine and Apocrine Glands?
Holocrine: They bud, burst, and are destroyed. secrete oil
Apocrine: Release sweat and lactation and do not get destroyed
what is the difference between synergism and antagonism?
antagonism: generally has two muscles that work in opposition to one another. (flexor and extensor)(straightening arm)
synergism: small muscles that modify the movement of larger muscles(picking up a pebble)
Characteristics of Skeletal, smooth, and cardiac muscle.
Skeletal: attached to the bone, voluntary, conscious control
Smooth: involuntary, no conscious awareness, makes up hollow organs, lining of blood vessels
Cardiac: muscle of the heart
What are some differences between smooth and skeletal muscle?
Skeletal: contracts in response to stimuli from the EXTERNAL environment, single innervation, rapid contractions
Smooth: contracts in response to stimuli from the INTERNAL environment, double innervation, slow and drawn out contractions
what is ‘tone’ and how does the stretch affect smooth muscle
tone: smooth muscle is always in a state of partial contraction.
it increases its contractions in response to stretch
what is the role of acetylcholine
it is a neurotransmitter that changes the membrane of the muscles so they are permeable to sodium
what is the role of sodium ions
in the depolarization process they go into the muscle and they reduce the difference to 0
what is the role of cholinesterase
it destroys Ach to restore polarity
what is the difference between the absolute refractory period and the relative refractory period?
Absolute: no additional stimulation and can produce a twitch
Relative: strong stimulus will initiate another contraction
why is it impossible to fatigue smooth muscle?
cant fatigue them because they have a very long refractory period
how do curare, an ACH imitator, and a cholinesterase blocker affect the myoneural junction
they both act as blockers. curare inactivates Ach so no impulse is generated.
what is the role of Ca++ in the sarcomere?
the role of Ca++ in sarcomere is to provide anaerobic energy
what is the role of Ca++ in the t tube
the t tube gets impulses and the after they relax they pull in Ca++
what role does Ca++ have with ATP
the ATP is needed to pull Ca++ back to muscle stays contracted
to what percentage of relaxed length can a skeletal muscle maximally contract?
70% of its length
what is the muscle spindle (golgi tendon structure)? and what is its purpose?
it is used to prevent muscles from tearing loose. it comes from the CNS (baby learning to walk and dropping down the first few times is that)
