Unit 2 Flashcards
what are the 2 types of eyes
camera and compound
the most successful animals have _________ eyes
complex
vertebrae animals have _______ type of eyes
camera
insects have _______ type of eyes
compund
compound eyes have clusters of cell groups called __________
ommatidium
each _________ has its own lens and ______________
ommatidium
photoreceptors
what is the dominant photopigment across species
rhodopsin
the earliest eyes were probably something called
eyespots
what is the white of our eye called, and where it is located
sclera
all the way to the back of the eye
what is the choroid in the eye
provides blood supply
the fibrous layer of the eye is
a. thin and durable
b. thick and durable
b. thick and durable
the fibrous layer of the eye is the ______ layer
a. innermost
b. middle
c. outermost
c. outermost
the posterior segment inside the eye contains a fluid called
vitreous humor
extrinsic muscles in the eye are _________ controlled
a. somatically
b. autonomically
a. somatically
what are the two muscles in the iris
radial and circular
when the circular muscles contract in the iris, the pupil ________
constricts
when the radial muscles contract in the iris, the pupil
dilates
the pupil constricts when in ______ light
bright
the pupil dilates when in ______ light
dim
the pupil movement is _________ controlled
a. somatically
b. autonomically
b. autonomically
the lens precisely changes shape to focus light on the _______
retina
what are lenses made of
crystallins
- some of the most stable proteins in the body
Do lenses have blood supply?
No- avascular
what do suspensory ligaments in the eye do
controls the curvature of the lens
a single neuron and all the muscle fibers it innervates
motor unit
when ciliary muscles contract, the suspensory ligaments _______
relax
the lens becomes more convex (bulged) when ciliary muscles _________ and suspensory ligaments ______
contract
relax
light is refracted 3 times along the eye:
- entering cornea
- entering lens
- leaving lens
what is refraction of light
bending light
majority of refraction comes from the ________
cornea
change in lens curvature allows for
fine focusing
when there is more bulge of the eye, there is more _________ that the eye can do
refraction
pupillary constriction is a ________ stimulation using Ach/NE?
parasympathetic
Ach
pupillary dilation is a ________ stimulation using Ach/NE?
sympathetic
NE
when focusing for close vision, the pupil _______ and the lens _______
constricts
bulges
when focusing for far vision, the pupil ______ and the lens ________
dilates
decreases refraction (less bulge)
convergence of the eyeballs happens when
our eyes move together and point inward when we look at near objects
Light will pass through the ________ before passing through the lens
pupil and cornea
Which of the following structures of the eye is/are not responsible for the refraction and focusing of light?
- Retina
- Lens
- Cornea
- Pupil
1 and 4
what is the blind spot in the eye called
optic disc
developmental outgrowth of the brain
retina
what are the 2 types of photoreceptors
rods and cones
the optic disc ______ photoreceptors
lacks
the ______________ is the site where the optic nerve leaves the eye
optic disc
_____ photoreceptors are used for dim light
rod
are rods or cones more numerous
-which is more sensitive?
rods
rods
the _______ only contains cones
macula lutea
_____ are used for high resolution color vision
cones
the process by which light is converted into electrical signals
phototransduction
photoreceptors are turned _____ when there is a lack of light
on
what absorbs light and produces a reaction
chromophores
there is ________ when we see
hyperpolarization
there is ________ when we do not see
depolarization
when light hits rhodopsin what is activated
G-Protein (transducin)
what does transducin turn on in phototransduction
PDE enzyme
when PDE is turned on by transducin, cGMP becomes
GMP
when cGMP becomes GMP, the ion channels
close
at rest (no phototransduction) cGMP allows ion channels to _____, and lets cell ________
open
depolarize
When light rays hit a rod cell in the retina, the rod ____________ because fewer cyclic nucleotide (cGMP gated) ion channels are _______
hyperpolarizes
open
when light hyperpolarizes a photoreceptor, what stops being released
glutamate
when photoreceptors depolarize, what is released
glutamate
glutamate inhibits what
bipolar cells (release neurotransmitters)
______ cells come together in the back of the eye and form the optic nerve
ganglion
ex of a biological clock
circadian rythym
sleep/wake cycle is influenced by
light
what part of the brain regulates the circadian clock
SNC in the hypothalumus
when light hits iPRGCs, it sends an _____________ and instructs the hypothalamus to __________________
AP
not activate pineal gland
when decreasing light, iPRGCs have less AP, which stimulates the ________ to release _____________
pineal gland
melatonin
nearly half of the body’s mass is made of what
muscle
skeletal muscles are striated, meaning they are
striped
skeletal muscles are ________ controlled
a. autonomously
b. somatically
somatically
the three layers of muscle create a structure called a
tendon
what are the 3 layers of muscle
- epimysium
- perimysium
- endomysium
connective tissue surrounding the entire muscle
epimysium
fibrous connective tissue surrounding fasicles
perimysium
groups of muscle fibers
fasicles
connective tissue surrounding each muscle fiber
endomysium
smaller motor units have ______ control
fine
what is within T-tubules
voltage gated ion channels
what does the Sarcoplasmic Reticulum (SR) function in
regulation of intracellular Ca2+ levels
what is the functional unit of a skeletal muscle fiber
sarcomere
what are sarcomeres made up of
thick and thin filaments
- myosin and actin
the thick filament in a sarcomere is
myosin
the thin filament in a sarcomere is
actin
Sarcomere is the region between 2 successive
Z discs
the Z disc anchors _____
thin filaments (actin)
an I band has no overlap between
actin and myosin
the myosin has ______ globular ______
2
heads
the 2 heads for myosin are binding sites for _________ and ________
ATP
actin
tropomyosin are on _______ and they function to
actin
binds to actin and inhibits myosin binding to actin
troponin are where _____ binding occurs and ____
myosin
Ca2+
what is a neuromuscular junction
axon ending with a single muscle fiber
generation of AP in skeletal muscle is caused by changes in charges in ____________
sarcolemma RMP
AP from the neuron reaches the nerve terminal and opens Ca2+ gates. This causes the release of which neurotransmitter across the synaptic cleft
ACh
when ACh diffuses into the muscle sarcolemma, __________ open and AP travels down ________
ligand gates channels
T-Tubule
ionic conditions of resting state are restored by
Na+/K+ pump
the muscle fiber cannot be stimulates during ______________ until what is complete
refractory period
repolarization
the latent period is period of time with/without contraction
without
when T-tubules depolarize, _______ change formation
DHPRs
when DHPRs change formation, this causes ______ to open and allows ______ in the SR to diffuse out
RyRs
Ca2+
_______ allows muscle fibers to contract
Ca2+
what frees the actin filament so it can interact with myosin
Ca2+
at low Ca2+ levels, tropomyosin ________ and muscle fiber is _________
blocks active sites on actin
relaxed
at high Ca2+ levels, _____ moves tropomyosin to allow _______
- muscle is _______
troponin
Ca2+ to bind to troponin
-contracted
________ break and form several times, which moves thin filaments closer to
cross bridges
sarcomere
in a contracted muscle
1. size of sarcomere ________
2. size of I band __________
3. distance between z discs __________
4. A band _________
- decreases
- decreases
- decreases
- stays the same
what causes cross bridge to break apart
ATP
ATP causes myosin and actin to
disengage
cocking of myosin head occurs when _____ is ________
ATP
hydrolyzed (ATP-> ADP+P)
every time cross bridge disengages, need a new _____ to have another _________
ATP
contraction
tension is the highest in the ____________ period
contraction
what are some ways muscle relaxes
- stimulation of nerves stops
- muscle fiber repolarizes (closes Ca2+ gate in SR)
- troponin tropomyosin complex recreated
- no more ATP
muscle contraction causes shortening
concentric
muscle contraction causes lengthening
eccentric
there is no shortening of the muscle, but tension increases
isometric
how do we increase the strength of contractions? (2)
- activation of more motor units
- increases muscle fiber size
- repeated stimulation
what is max stimulation called
tetanus
what is twitch summation
muscle fiber is restimulated before it has completely relaxed
- 2nd twitch added to 1st twitch
creatine phosphate is stored in
muscle fibers
where is creatine phosphate cleared out
kidney
does creatine phosphate use oxygen
no
aerobic respiration occurs when ______ is present
oxygen
aerobic respiration is fueled by ________ stores and ________ delivered by blood
glycogen
fatty acids
used for endurance activities
aerobic respiration
aerobic respiration is faster/slower because
slower
requires delivery of O2 and glucose through blood
uses no oxygen
anaerobic
in anaerobic respiration, ______ is converted to ________
pyruvic acid
lactic acid
anaerobic respiration produces ______ ATP but occurs ________
fewer
quicker
used for intense, quick activity
anaerobic
too much lactic acid buildup causes
muscle fatigue
slow to contract but are most resistant to fatigue
slow oxidative (type 1)
fast to contract but less resistant to fatigue
fast oxidative (type 2a)
fast to contract but are not resistant to fatigue
fast oxidative (type 2b)
there is rich blood supply in this type of muscle fiber, making it a darker meat
slow oxidative (type 1)
which muscle type is better equipped for aerobic respiration
slow oxidative (type 1)
this type of muscle fiber relies mostly on anaerobic respiration
fast glycolytic(type 2b)
excess post exercise oxygen consumption (EPOC) refers to
replenishing extra O2 and getting body to pre-exercise state
muscle fatigue results from a deficit of _______ (not depletion)
ATP
DHPR receptors change shape and cause ______ to open
Ryrs
crush bones to release Ca2+
osteoclasts
bone is the hardest ____________ tissue in the body
connective
the axial skeleton includes
skull, rib cage, vertebrae
the appendicular skeleton includes
bones of upper and lower limbs and girdles
forms the bone matrix (builds bone)
osteoblasts
maintains bone tissue (adult bone tissue)
osteocytes
bone stem cells
osteogenic cells
_________ gives bone its flexibility
collagen
_______ gives bone its rigidity
inorganic ions (ca2+)
what is the center shaft of the long bone called
diaphysis
what are the ends of the long bone called
epiphysis
the ______________ is the remnant of the epiphyseal plate
epiphyseal line
what are the 2 kinds of bone marrow
red and yellow
this marrow allows for more endurance
yellow (fat production)
what are the types of bone (2)
compact
spongy
____________ are at the ends of bone and are used for shock absorption
spongy bone
the walls of bone are made of ____________
compact bone
runs through the center of the compact bone and allows passage of blood vessels and nerves
central canal
lie at right angles and connect blood & nerve supply of the periosteum to the central canal
perforating canals
what is the structural unit of compact bone
osteon
osteons are made of _______ tubes of bone matrix known as ___________
concentric
lamellae
_____________ are stress sensors and signal to osteoblasts and osteoclasts to repair the bone
osteocytes
____________ ossification occurs in flat bones of the skull and the clavicles
intramembranous
endochondral ossification means
within cartilage
calcium balance in the body is hormonal ________ feedback
negative
which ions/minerals are important for bone health
Ca2+, Vit D, Vit K, Magnesium
what is the difference between red and yellow blood marrow
red- produces RBC
yellow- fat storage
osteons are made of concentric circles called
lamalla
how does exercise impact bones
gravity and stress placed on bones cause them to be stronger (osteoblast stimulation)
blood cell formation in red bone marrow
hematopoiesis
red blood cell formation is called
erythropoiesis
too few RBC causes tissue
hypoxia
too many RBC increases ______________
blood viscosity
hypoxia means
inadequate O2 supply
direct stimulus for erythropoiesis
EPO- hormone erythropoitein
when there is too little O2 in the blood, what happens
EPO is released to produce more RBC
________ stimulus is low blood Ca2+
PTH
when PTH is released into the bloodstream, what are its effects on
1. bone
2. kidney
3. small intestine
- bone: osteoclast activity increases (more Ca2+ in blood)
- kidney: reabsorbs Ca2+ and activates Vit D
- small intestine: increased absorption of Ca2+ bc of Vit D
____________ stimulus is high blood Ca2+
calcitonin
when calcitonin is released into the bloodstream, what are its effects on
1. bone
2. kidney
3. small intestine
- bone: increased osteoblast activity (use more Ca2+ in bone to take away from blood)
- kidney: Ca2+ is secreted to the urine, and vit D is not activated
- small intestine: Ca2+ is not absorbed (bc no vit D)
PTH and calcitonin are released from
parathyroid and thyroid gland
when ion channels are kept open bc of cGMP, releases _________ that inhibits bipolar cells from firing AP
glutamate
glutamate causes bipolar cells to
not fire AP
in endochondral ossification, ______ in diaphysis calcifies and dies
cartilage
in endochondral ossification, when cartilage calcifies and dies, this opens up a cavity that is invaded by the
periosteal bud
the periosteal bud in endochondral ossification creates
primary ossification center
vit D is made by the sun hitting skin and precursor 1 is stored in the _________. When PTH comes, vit D in the kidney acitvates
liver
why do animals need to breathe?
intake O2 for cellular respiration (that makes ATP)
whole body respiratory surface animal limitations
size of the animal (has to be small)
external gill respiratory surface animals requires
constant flow of water moving past the gills
external gills are in _________ contact with water
direct
internal gills must have water ___________
brought into them
gill respiratory surfaces actively brings water into them and ______________- gills
pushes it across gills
in gill respiratory surfaces, water flow goes ____________ of blood flow to maximize concentration gradient
opposite
diffusion is greatest when the ___________ is greatest
concentration gradient
why is the trachea not a closed ring
so esophagus can travel food down it
the larynx is where _________________________ to the ___________
air travels down to the trachea
what is the conducting zone in respiration
brings in o2 and removes co2
- includes structures such as nasal cavity, larynx,
what is the respiratory zone in respiration
the actual site of gas exchange (alveoli, bronchioles)
alveolar sacs contain clusters of __________
alveoli
high surface area sites for gas exchange
alveoli
the gas exchange in respiration with blood happens in the _____________ that lays on top of _____________
capillary bed
alveoli
alveoli and capillary walls are ________ to allow for what
thin
- easy to diffuse gas across by simple diffusion
cuboidal alveolar cells secrete ______________ that do what?
surfactants
- reduces attraction of water to each other to keep alveoli open
if we did not have _________, alveoli would not stay open and collapse
surfactants
respiratory distress syndrome (RDS) in infants is caused by
lack of surfactants
process of breathing- movement of air into and out of the lungs
pulmonary ventilation
O2 and CO2 exchange between lungs and blood
external respiration
O2 and CO2 exchange between systemic blood vessels and tissues
internal respiration
pressure exerted by air surrounding the body
atmospheric pressure
pressure always wants to go form
hight to low
what ensures that lungs remain inflated
intrapleural pressure
air goes ______ the lungs when negative respiratory pressure (less than Patm)
into
air goes ______ the lungs when positive respiratory pressure (more than Patm)
out of
you breathe in bc intrapulmonary pressure is ____________
negative
what kind of pressure is always negative
intrapleural
each lung is contained in a
pleural sac
in the pleural sac, one layer is connected to the lungs, and the other is ______________ to __________________
suctioned to the thoracic wall
pulmonary ventilation involves
internal and external expiration
what is thr relationship between pressure and volume
when pressure increases, volume decreases and vice versa (indirect)
inspiration (gas flow into the lungs) is a _____________ process
a. active
b. passive
a. active
during inspiration, which inspiratory muscles contract
diaphragm and external intercostals
in inspiration, the thoracic volume _________ which leads to lungs expanding, and pressure ____________
increases, drops (decreases)
when thoracic cavity volume increases in inspiration, lung volume ______________ and lung pressure __________________
increases, decreases
external intercostals contract in what direction
- diaphragm?
up and out
- down
expiration is considered a ________ process
a. active
b. passive
b. passive
in expiration, the inspiratory muscles ___________
relax
in expiration, thoracic cavity volume _______________, and lungs volume ____________ and lungs pressure _______________
decreases
decreases, increases
air flows out of lungs down its pressure gradient until
Ppul=Patm
- Ppul = pulmonary pressure
what is external respiration
exchange of O2 and CO2 across respiratory membranes
what is the rate of diffusion influenced by (3)
- thickness of membrane
- surface area of membrane
- partial pressure gradients
external respiration is exchange between ______________ and ________________
alveoli and capillary wall
the thicker the membrane, the _______ the rate of diffusion
lower
IN EXTERNAL:
pressure of CO2 in the lungs is higher in the __________ than the alveoli
- meaning the CO2 will move to the __________
blood
- alveoli
IN EXTERNAL:
the pressure of O2 in the lungs is higher in alveoli than in ___________,
- meaning O2 will move into _______________
blood
blood
in external respiration,
1. O2 goes to the ________
2. CO2 goes to the ____________
- alveoli–> blood
- blood into alveoli
internal respiration includes exchange between _____________ and _______________
capillaries and body tissue
internal respiration partial pressure and diffusion gradients is __________ to external respiration
opposite
in INTERNAL respiration, pressure of tissue O2 is __________ than bloods
- meaning O2 goes ______________
lower
from blood to tissue cell
in INTERNAL respiration, pressure of tissue CO2 is __________ than bloods
- meaning CO2 goes ______________
higher
from tissue cell to blood
n INTERNAL respiration
1. CO2 goes
2. O2 goes
- tissue–> blood
- blood–> tissue
the O2 going into tissue cells in internal respiration does what
- where what is the byproduct that leaves
fuels cellular respiration
-CO2
The end blood leaving external is the ___________ blood of internal
incoming
how is O2 transported throughout the body
hemoglobin on RBC
RBCs lack a _________, which makes more space for _______________
nucleus
hemoglobin
hemoglobin- O2 combination
oxyhemoglobin
hemoglobin that has released O2
deoxyhemoglobin
when O2 binds to hemoglobin, the affinity for O2 _______________
increases
when O2 releases from hemoglobin, the affinity for O2 _______________
decreases
hemoglobin when bound to O2 has a _____________ shape
specific
a fully saturated hemoglobin carries _________ O2
4
what.3 forms is CO2 transported in blood
- bound to globin of hemoglobin
- transported as bicarbonate ions (HCO3-) in plasma
- dissolved in plasma
when CO2 goes into RBC, it combines with __________ and makes carbonic acid, which dissociates into _________ and ____________
H2O
H+ and HCO3- (bicarbonate ion)
primary control center for respiration
medulla
the rise of _______ and _________ in blood helps indicate to hemoglobin to release O2
H+ and CO2
internal respiration (body cells) amount of O2 transported by hb affected by _______ and ___________
- called _______ effect
PCO2 and pH
Bohr (b-body)
the __________ effect helps the lungs release carbon dioxide from carboxyhemoglobin
Haldane
haldane effect involves oxygentaed blood in the lungs which increases _______ of _______________
removal
CO2
haldane effect relates to _________ respiration
external
increase in temperature ________ Hb affinity for O2 because of change of shape
decreases
The S shaped nature of the oxygen-hb dissociation curve allows for _____ to be released for exercise without big change in __________
a lot of O2
- O2 pressure
peripheral chemoreceptors are in
neck region
central chemoreceptors are only sensitive to __________ in the ________________
CO2 in cerebrospinal fluid
peripheral chemoreceptors are sensitive to
blood PO2, PCO2, and H+
when CO2 in the blood is high,
1. H+ is ________
- high
rise in body temp. __________ respiratory rate
increases
intrapulmonary pressure in the pressure in the __________
alveoli
