Chapter 50 Flashcards
1
Q
Sensory processes
A
convey information about an animals environment to its brain, muscles and skeletons carry our movements as in structed by brain
2
Q
All stimuli
A
represent forms of energy
3
Q
Sensation involves…
A
converting energy into change in membrane potential of sensory receptors
4
Q
General pathway of simple response pathway
A
- Sensory input
- Integration
- Motor Output
5
Q
(5) Sensory Receptors
A
- Mechanoreceptors
- Chemoreceptors
- Electromagnetic Receptors
- Thermoreceptors
- Pain Receptors
6
Q
Mechanoreceptors
A
sense physical deformation caused by stimuli (pressure, stretch, motion and sound)
7
Q
Mammalian sense of touch relies on
A
Mechanoreceptors that are dendrites of sensory neurons
8
Q
Chemoreceptors
A
transmit info about the total solute concentration of a solution
- specific chemoreceptors respond to individual kinds of molecules.
- When a stimulus molecule binds to a chemoreceptor, it becomes (more or less) permeable to ions
9
Q
Electromagnetic receptors
A
detect e-magnetic energy (light, electricity, magnetism)
-migration patterns reliant on this
10
Q
Thermoreceptors
A
respond to heat/cold
- help regulate body temp by signaling body surface and core temperatures
- mammals have many kinds–specific for a temperature range
11
Q
Nociceptors
A
(Pain Receptors) detect stimuli that reflect harmful conditions.
-respond to excess (heat, pressure, chemicals released from damaged or inflamed tissues)
12
Q
Hearing and perception of body Equilibre.
A
Related in most animals
-both senses; settling particles/moving fluid is detected by mechanoreceptors
13
Q
Statocysts
A
Organ in which mechanoreceptors for most invertebrates to maintain equilibrium
14
Q
Statoliths
A
granules that detect movement in mechanoreceptors in statocysts.
15
Q
Many arthropods sense sounds
A
w/
- body hairs (vibrate)
- localized *ears consisting of tympanic membrane stretched over an internal air chamber
16
Q
Hearing and equilibrium in mammals
A
most terrestrial vertebrates; sensory organs for them closely associated in the ear
17
Q
Cochlea
A
has two large chambers:
- vestibular canal
- tympanic canal
18
Q
Organ of corti
A
contains the mechanoreceptors of the ear
19
Q
Hearing (part 1)
A
- percussion waves in the air vibrate tympanic membrane.
- Three bones of middle ear transmit them to oval window on cochlea
- creates pressure waves in cochlear fluid that travel through vestibular canal.
20
Q
Three bones of middle ear
A
- Malleus
- Incus
- Stapes
21
Q
Hearing (part 2)
A
- pressure waves in canal cause vibrations in basilar membrane. Bending Hair cells
- Hair cells bending depolarize membranes of mechanoreceptors
- send action potentials to the brain via auditory nerve
22
Q
Transduction in cochlea
A
fluid waves dissipate when they strike the round window at the end of the tympanic canal
23
Q
Equilibrium
A
organs of inner ear detect body movement, position and balance:
- Utricle and Saccule
- Three semicircular canals
24
Q
Utricle and Saccule
A
contain granules called otoliths –used to perceive position relative to gravity/linear movement
25
Three semicircular canals
contain fluid, detect angular movement in any direction
| (X, Y, Z) planes
26
Fish/aquatic amphibians hearing+Equilibrium
- only pair of inner ears near brain
| - lateral line system (along both sides of their body)
27
Lateral line system
contains mechanoreceptors that detect+respond to water movement
28
Underlying mechanism for capturing light
is the same for animals, although the diverse set of organs for vision.
-suggests a common evolutionary origin
29
Light detectors all contain
photoreceptors (cells that contain light-absorbing pigment molecules
30
Light-Detecting organ
(most invertebrates have one)
- simplest is that of planarians
- pair of ocelli (called eyespots) located near head
31
Ocelli
allows planarians to move away from light to seek shaded locations
32
Compound eyes
(insects and crustaceans)
consist of many light detectors (called ommatidia)
-effective at detecting movement
-insects have excellent colour vision and can see in UV range
33
Single lens eyes
(some jellies, polychaetes, spiders, many molluscs)
*eyes of all vertebrates have a single lens
camera-like principle:
-iris changes diameter of pupul (control amount of light entering)
34
Vertebrate visual system
- eye detects colour and light
| - brain assembles info and perceives image
35
Rhodopsin
where transduction of visual information to NS begins. when light induces conversion:
Cis-retinal to trans-retinal
36
Vertebrates that see colour well
- most fish
- amphibians and reptiles, birds
- humans and primates (not many other mammals)
37
Two types of photoreceptors in human retina
- Rods (vision at low light levels)
| - Cones (active at higher light levels, colour vision)
38
Noctornal mammals
usually high proportion of rods in retina
39
processing of visual info
done by brain
40
Fovea
the center of the visual field
- no rods
- high density of cones
41
Focusing: Near vision
(accommodation)
- cilliary muscles contract, pulling border of choroid toward lens
- suspensory ligaments relax
- lens becomes thicker+rounder, thus focusing on nearby objects
42
Focusing: Distance vision
- cilliary muscles relax
- border of choroid moves away from lens
- suspensory ligaments pull against lens
- lens becomes flatter+focusing on distant objects
43
In terrestrial animals: Gustation
(taste) is dependent on the detection of tastant chemicals
44
In terrestrial animals: Olfaction
(smell) is dependent on the detection of odorant molecules
45
Aquatic mammals (olfaction and gustation)
there is no distinction between the two
46
Taste receptors of insects
in sensory hairs located on:
- feet
- mouth parts
47
Taste in mammals
receptor cells for taste are modified epithelial cells, organized into taste buds
48
Five taste perceptions
1. Sweet
2. Sour
3. Salty (researchers havent identified the receptors for it yet)
4. Bitter
5. Umami (elicited by glutamate
49
Papillae
projections on most taste buds; detect the five types of taste
50
Taste receptors are of three types:
1. G protein-coupled receptors (GPCRs)
2. Thermoreceptor proteins (TRP)
3. Sodium channels
51
1. GPCRs
sensations of
- sweet
- umami
- bitter
52
2. TRP
Capsaicin and sour
53
3. Sodium channel
receptor for salty
54
Olfactory receptor cells
neurons that line the upper portion of nasal cavity
55
Binding of odorant molecules to receptors
triggers a signal transduction pathway; sending action potentials to the brain
56
Interaction of senses
although receptors/brain pathways for taste and smell are independent, they interact
57
Vertebrate skeletal muscle
-
- muscle cell contra
- moves bones and the body, characterized by a hierarchy of units that get smaller and smaller
58
muscle activity
is a response to input from NS
59
muscle cell contraction relies on...
- interaction between thin filaments (mainly actin) and motor protein (myosin)
- reaction is dependent on ATP
60
Skeletal muscle
consists of bundle of long fibers
- each a single cell
- running parallel to length of the muscle
* AKA: Striated muscle
61
Myofibrils
bundled together longitudinally to create unit of each muscle fiber.
62
Myofibrils composition
composed of two kinds of myofilaments:
- Thin Filaments (two strands of both actin and regulatory protein)
- Thick filaments (staggered arrays of myosin)
63
Striated muscle
(skeletal muscle)
| has a regular arrangement of myofilaments creating pattern of light & dark bands
64
Functional unit of a muscle
Sarcomere
| -bordered by Z lines (where filaments attach)
65
Sliding-Filament model (part 1)
according to this model:
- Thin and thick filaments slide past one another (longitudinally)
- powered by myosin molecules
66
Sliding of filaments
Relies on interaction between:
- "head" of myosin binds to actin filament
- forms cross-bridge, pulls thin filament toward center of sarcomere
67
Muscle contraction requires
- repeated cycles of binding and release
| - sustained muscle contraction dependent ATP generated by Glycolysis aerobic respiration.
68
Stimulus learing to contraction of a muscle fibre
is an action potential in a motor neuron that makes a synapse with a muscle fibre
69
Regulation of skeletal muscle contraction
synaptic terminal of the motor neuron releases acetylcholine.
- depolarizes the muscle; causing it to produce action potential
- AP travel to interior of muscle fiber along Transverse (T) tubules
70
Sarcoplasmic Reticulum (SR)
releases Ca 2+ ions in respinse to AP along T tubules.
-Ca2+ binds to troponin complex on thin filaments, exposing myosin-binding sites allowing the cross bridge cycle to proceed
71
Muscle cell relaxes
when motor neuron input stops
- transport proteins in SR pump Ca2+ out of cytosol
- regulatory proteins bound to thin filaments shift back to myosin-binding sites
72
Cardiac muscle
- found only in heart
- consist of striated cells electrically connected by intercalated disks
- can generate AP's without neural input
73
Smooth Muscle
- found mainly in walls of hollow organs (digestive tract)
- Contractions are relatively slow, may be initiated by the muscles themselves, or my stimulation from neurons in Autonomic NS
74
Skeletal muscles attached in
Antagonistic pairs
| -actions of which are coordinated by the nervous system
75
Skeletal system
- provides rigid structure to which muscles attach
| - support, protection and movement
76
Three main types of skeletons
1. Hydrostatic skeletons (lack hard parts)
2. Exoskeletons (external hard parks)
3. Endoskeletons (internal hard parts)
77
Hydrostatic skeleton
(cnidarians, flatworms, nematodes, annelids)
- fluid held under pressure in closed compartment
- some use this for peristalsis
78
Exoskeletons
(most molluscs, arthropods)
- Hard encasement deposited on surface of animal
- Arthropods have jointed exoskeleton called a cuticle.
79
cuticle
strong and flexible made of (polysaccharide) chitin
80
Endoskeleton
hard, internal skeleton buried in soft tissue
81
Weight of a body increases
with the cube of its dimensions
82
strength of body increases
with the square of its dimensions
83
Mammals and birds, position of
legs relative to the body very important indicator of how much weight its legs can bear.
84
Locomotion
active travel from place to place
| -energy expended to overcome friction and gravity
