Option: Communication Flashcards

Question 1

Q

Identify the role of receptors in detecting stimuli

Answer

A

Stimulus: Change in internal/external environment; detected by receptors & response triggered

Receptors: Single cells or concentrated in areas to form sense organs (ear, eye)

Photoreceptor: Sensitive to light energy (UV, visible
light)

Mechanoreceptor: Mechanical energy (tough, pressure, gravity)

Thermoreceptor: Heat and cold

E.g. Tough hot plate; thermoreceptors in skin; detect heat and pain→ withdraw fingers

Coordination needs link between receptors and effectors (muscles/glands)
Link carried out by nervous system

Question 2

Q

Identify data sources, gather and process information from secondary sources to identify the range of senses involved in communication

Answer

A

Communication: Sending and receiving meaningful info

Communicator (sending info) needs to have signalling device. E.g. voice box

Recipient needs structure to detect. E.g. Ears to hear

Sight
Lion: Hairs on mane stand up (larger) when another male in environment

Sound
Lion: Roar to intimidate other male; aggressive warning

Taste
Ants follow pheromone markers (left by others) to find food

Smell
Fish emit odours→ establish rank in social group

Touch
Humans hug and shake hands to greet

Question 3

Q

Explain that the response to stimuli involves:

Answer

A

Stimulus, Receptor, Messenger, Effector, Response

CNS→ triggers response to stimulus (receptors change stimuli into electrochemical signals)

Electrochemical travel along nerves; transmit info to
CNS; processed/interpreted→ response initiated

CNS→ impulses along nerves to effector organs (carry out response)

Question 4

Q

Describe the anatomy and function of the human eye, including the:

CONJUNCTIVA

Answer

A

Thin transparent membrane→ protects front of eye

Question 5

Q

Describe the anatomy and function of the human eye, including the:

CORNEA

Answer

A

Transparent→ light can enter (no blood vessels)

Curvature→ bends/refract incoming light rays to converge & land at back of eyeball

Question 6

Q

Describe the anatomy and function of the human eye, including the:

SCLERA

Answer

A

Outermost layer; non-elastic, tough tissue→ protects inner layers & maintains shape of eye

Site of muscle attachment→ eye movement in socket

Question 7

Q

Describe the anatomy and function of the human eye, including the:

CHOROID

Answer

A

Middle coat; most of blood vessels

Back layer→ black to reduce scattering of light

Question 8

Q

Describe the anatomy and function of the human eye, including the:

RETINA

Answer

A

Thin, delicate→ contains photoreceptors (rods/cones) → responds to light

Question 9

Q

Describe the anatomy and function of the human eye, including the:

IRIS

Answer

A

Coloured part of eye; smooth muscle→ control size of pupil

Question 10

Q

Describe the anatomy and function of the human eye, including the:

LENS

Answer

A

Transparent, biconvex (bulges outwards)→ refracts light rays; directs onto retina (focused image formed)

Elastic; round to flatter surface→ accommodates near and far vision

Question 11

Q

Describe the anatomy and function of the human eye, including the:

AQUEOUS AND VITREOUS HUMOUR

Answer

A

Transparent, watery liquid→ contains dissolved nutrients

Aqueous; Provides nutrients for cornea and lens (that don’t have own supply)

Vitreous; Material fills remainder of eyeball; maintains shape and provide nutrients

Question 12

Q

Describe the anatomy and function of the human eye, including the:

CILIARY BODY

Answer

A

Muscles and ligaments→ adjust curvature of lens

Ciliary muscles relax→ lens flat → distant vision

Muscles contract→ lens round→ near vision

Question 13

Q

Describe the anatomy and function of the human eye, including the:

OPTIC NERVE

Answer

A

Nerves pass through skull→ carry electrochemical signals from retina to brain

Question 14

Q

Use available evidence to suggest reasons for the differences in range of electromagnetic radiation detected by humans and other animals

HUMANS

Answer

A

380-760 nm

All colours in visible light (no UV)

Active during day→ Need to distinguish colours in environment

Question 15

Q

Use available evidence to suggest reasons for the differences in range of electromagnetic radiation detected by humans and other animals

INSECTS (BEES)

Answer

A

300-650 nm

UV range, blue, green (NO RED)

UV patterns on flowers→ attract bees to pollen and nectar

Question 16

Q

Use available evidence to suggest reasons for the differences in range of electromagnetic radiation detected by humans and other animals

VERTEBRATES (BIRD AND SNAKE)

Answer

A

SNAKE
400- 850 nm
Blue, green, red, UV
Relies on infrared→ locate prey in dark burrows

BIRD
460-700 nm
Blue, green, red
Distinguish environment when flying

Question 17

Q

Identify the limited range of wavelengths and the electromagnetic spectrum detected by humans and compare this range with those of other vertebrates and invertebrates

Answer

A

Humans visible wavelength; 380-760nm) → only small part of spectrum (No UV light)

Flying animals detect polarised light→ for navigation in flight

Objects absorb some wavelengths; reflect other→ Colour is light reflected

Question 18

Q

Identify the conditions under which the refraction of light occurs

Answer

A

Refraction: Bending light as it travels from one medium to another (air to water)

Move through dense medium→ slows down and bends towards normal

Pass through biconvex (eye lens) → light rays refracted to focal point (retina on back of eye)

Eye lens→ changes shape; form image of near and far objects

Question 19

Q

Plan, choose equipment or resources and perform a first hand investigation to model the process of accommodation by passing rays of light through convex lenses of different focal lengths

Answer

A

Lightbox; different focal lengths from concave and convex

Convex→ Rays converge

Concave→ Rays diverge

Question 20

Q

Identify the cornea, aqueous humor, lens and vitreous humor as refractive media

Answer

A

Density→ All similar (close to water) → refract light passing through

Refractive power of air→ Lower than power of eye
Light passes from air to refractive surfaces

Greatest degree of refraction in eye occurs at boundary of air and cornea

Question 21

Q

Analyse information from secondary sources to describe changes in the shape of the eye’s lens when focusing on near and far objects

Answer

A

Distant vision→ Flat (muscles relax; pull ligaments taut)

Near vision→ Increased curvature (muscles contract; ligaments slacken) → lens becomes round

Question 22

Q

What are cataracts?

Answer

A

Clouding of lens; obstructs path of light into eye→ blurred vision; looking through ‘veil’

Due to ageing or injury to eye

When proteins build up in lens; new and old cells compacted into centre

Question 23

Q

Technology for cataracts and implications for society

Answer

A

TECH
Phacoemulsification: Probe inserted (tiny incision) cataract broken into pieces; suctioned out

Lens implant; permanent into eye→ focuses light on retina

Extracapsular extraction: Large incision; removes centre in one piece; (NEEDS STITCHES)

IMPLICATIONS FOR SOCIETY
Millions have vision restored; ends avoidable blindness→ return to daily activities

Increases life expectancy; gives more independence (patients and caregivers return to work)

Question 24

Q

Compare the change in refractive power of the lens from rest to maximum accommodation AND

Identify accomodation as the focusing on objects at different distances, describe its achievement through the change in curvature of the lens and explain its importance

Answer

A

Change in curvature of lens→ accommodation

Increased lens curvature→ Thick lens; decrease focal length (increase refraction)

Decreased curvature→ thin lens; increases focal length (decrease refraction)

Low refractive power at rest→ distant objects (thin/flat lens)

High refractive power at max accomodation→ Near objects (round lens)

Question 25

Q

What is Myopia?

Answer

A

Shortsightedness

Distant objects unclear→ Near objects well

Distant objects fall in front of retina (not on it) → Light rays bent incorrectly→ Blurred vision

When eyeball too LONG for lens or cornea too CURVED

Question 26

Q

What is Hyperopia?

Answer

A

Long sightedness

Close up objects unclear→ Distant objects well

Image falls behind retina (not on it) → Light rays diverge → blurred vision

When eyeball is too rounded or lens too FLAT to alter light

Question 27

Q

Technologies to correct Myopia

Answer

A

Orthokeratology; Special lenses at night→ reshape cornea while asleep; in morning temporarily retains new shape

Contact lenses or glasses
Myopia→ CONCAVE (Thicker outwards, thinner inwards) Bends light outwards to diverge before meets eye (extends focal length)

Laser surgery to change cornea curvature
PRK→ Outer cornea surface removed; laser shapes cornea

LASIK→ Cut and lift flap of cornea and reshape

Question 28

Q

Technologies to correct Hyperopia

Answer

A

Orthokeratology; Special lenses at night→ reshape cornea while asleep; in morning temporarily retains new shape

Contact lenses or glasses
Hyperopia→ CONVEX (Thinner outwards, thicker inwards) Bends light inwards to converge before meets eye (shortens focal length)

Laser surgery to change cornea curvature
PRK→ Outer cornea surface removed; laser shapes cornea

LASIK→ Cut and lift flap of cornea and reshape

Question 29

Q

Explain how the production of two different images of a view can result in depth perception

Answer

A

Depth perception: Ability to determine distances between objects & see in 3D

2 eyes at different positions; View from each eye slightly different

Images fused together in brain→ one 3D image produced

Brain calculates depth from slight differences in 2 images

Question 30

Q

Identify photoreceptor cells as those containing light sensitive pigments and explain that these cells convert light images into electrochemical signals that the brain can interpret

Answer

A

Light focuses on retina→ Photosensitive pigments in rods and cones absorb light→ generate electrochemical impulse→ Sent to brain via optic nerve

Rods and cones→ contain light sensitive pigments→ convert light to electrochemical signals

Acuity→ ability to see clear and precise image
Low visual acuity when high retinal convergence (more rods to one bipolar neuron)

High visual acuity when less convergence (less rods to one bipolar neuron)

Question 31

Q

RODS

Answer

A

Effective in low light (night vision)

Evenly distributed throughout retina

Sensitive to all wavelengths

One type of pigment (rhodopsin)

Poor visual acuity (Coarse detail)

Black and white

120 million cells

More sensitive to low light

Peripheral and vision vision

Question 32

Q

CONES

Answer

A

Bright light (day vision)

Concentrated in fovea

Sensitive to 3 wavelengths

3 types of pigment (iodopsin)

High visual acuity (Fine detail)

Colour

6-7 million cells

Less sensitive to low light

Central and detailed vision

Question 33

Q

Process and analyse information from secondary sources to compare and describe the nature and functioning of photoreceptor cells in mammals, insects and in one other animal

Planaria (Aquatic Flatworm)

Answer

A

Description of eye structure
Simple eyespots (resemble eyes) → can’t produce images; just tell light from dark
No lens to focus images

Refractive surface
No lens→ single layer of photosensitive cells respond to light

Photoreceptor cells
Little photoreceptor cells

Visual acuity
No image produced→ few photoreceptor cells

Image formed
No image→ just used to tell light from dark (for direction)

Role of photoreceptor cells
Determine direction/intensity of light

Response time
Flatworms move away from light source quickly after detection

Question 34

Q

Process and analyse information from secondary sources to compare and describe the nature and functioning of photoreceptor cells in mammals, insects and in one other animal

Insect (Bee)

Answer

A

Description of eye structure
Compound eyes (8000 light detecting units→ ommatidium)
Each ommatidium→ own lens to focus light onto photoreceptors

Refractive surface
Light passes through lens of ommatidium and cornea refracts incoming rays

Photoreceptor cells
16,000 light sensitive retinal cells

Visual acuity
Better than simple planaria but not as good as humans
Clearer images produced (Judge distances & see flowers when flying)

Image formed
Clearer than simple eyes but blurred in comparison to mammals

Role of photoreceptor cells
Detect movements in large FOV
Identify flower patterns from UV light

Response time
Quicker than mammals→ need to see clearly at speeds even when flying

Question 35

Q

Process and analyse information from secondary sources to compare and describe the nature and functioning of photoreceptor cells in mammals, insects and in one other animal

Mammal (Human)

Answer

A

Description of eye structure
Lens→ Behind pupil and iris (focuses light)
Retina→ Converts light into electrical impulses → carried to brain via optic nerve

Refractive surface
80% occurs in cornea (from air to eye)
Many refractive surfaces (cornea, aqueous/vitreous humor, lens)

Photoreceptor cells
6-7 million rods and cones

Visual acuity
Clear and precise in day (cones) → High acuity
Unclear at night (rods) → Low acuity

Image formed
Clear and inverted

Role of photoreceptor cells
Rods→ Peripheral and night vision
Cones→ Central and detailed colour vision
Detect light/movement

Response time
Rods→ Slow response, long integration time
Cones→ fast response, short integration time

Question 36

Q

Describe the differences in distribution, structure and function of the photoreceptor cells in the human eye

RODS

Answer

A

Distribution:
Evenly distributed across most of retina (absent from fovea)

Structure:
Elongated cells→ outer segment is long and narrow
Contains visual pigments→ stacked in layers of flattened membranes

Pigments:
Only Rhodopsin

Function:
Responsible for most of peripheral vision (detects movement)
Night vision; detect light and shadow contrasts
Sensitive to light so can operate in semi-darkness

Colour and wavelength of light to which cell is sensitive:
See in shades of black, white and grey

Question 37

Q

Describe the differences in distribution, structure and function of the photoreceptor cells in the human eye

CONES

Answer

A

Distribution:
Most concentrated in fovea

Structure:
Elongated cells→Outer segment is short and conical.
Broader than rods
Contains visual pigments→ stacked in layers of flattened membranes

Pigments:
Cones contain iodopsins (3 different types; one in each type of cone cell)

Function:
Responsible for colour vision- (each iodopsin is sensitive to primary colours)
Function best in daytime vision

Colour and wavelength of light to which the cell is sensitive
See in red, blue and green and other colours (combo of different cones)

Question 38

Q

Process and analyse information from secondary sources to describe and analyse the use of colour for communication in animals and relate this to the occurrence of colour vision in animals

Answer

A

Colour→ Warning to rivals, displays for mate attraction,
E.g. Male Peacocks feathers→ mate attraction and sign of being threatened

Food recognition→ Bird-pollinated flowers often red (sensitive to red)

Monarch butterfly→ yellow/black markings→ indicate poisonous

Birds→ Don’t use odour for territories or mates→ color is important

Question 39

Q

Outline the role of rhodopsin in rods

Answer

A

Rhodopsin (visual pigment) → protein molecule (opsin) + retinal (light absorbing part)

Main function→ To absorb light

Light strikes rhodopsin→ light energy absorbed→ rhodopsin changes from resting to excited state

Retinal becomes activated→ splits into free retinal part and protein opsin part

Activated pigment→ causes change in electrical impulse→ triggers release of neurotransmitter

Neurotransmitter stimulates bipolar cell→ generates cell impulse

Bipolar cell→ transmits electrochemical signal to ganglion cells→ carry signal to brain

Rhodopsin (temporarily bleached in presence of light) regenerated for reuse → recombine by enzymes

Question 40

Q

Identify that there are three types of cones, each containing a separate pigment sensitive to either blue, red or green light

Answer

A

Cone pigment→ iodopsin (3 different types→ each sensitive to 1 primary colour of light)

See in colour→ red, green, blue cone impulses sent to brain, interprets signals as colour perception

All colours seen are combination of colours

Overlap in light range absorbed by 3 cone pigments (particularly red and green) → In absence of red cones, green will detect red light

Question 41

Q

Identify that there are three types of cones, each containing a separate pigment sensitive to either blue, red or green light

Blue

Answer

A

Cone stimulated by light colour
Blue

Colour detected by cone
Blue

Pigment present
Opsin Blue

Wavelength of light cone sensitive to (nm)
Approx 380-510

Peak wavelength Sensitivity (nm)
455

Question 42

Q

Identify that there are three types of cones, each containing a separate pigment sensitive to either blue, red or green light

RED

Answer

A

Cone stimulated by light colour
Red

Colour detected by cone
Red

Pigment present
Opsin Red

Wavelength of light cone sensitive to (nm)
Approx 485-640

Peak wavelength Sensitivity (nm)
625

Question 43

Q

Identify that there are three types of cones, each containing a separate pigment sensitive to either blue, red or green light

GREEN

Answer

A

Cone stimulated by light colour
Green

Colour detected by cone
Green

Pigment present
Opsin Green

Wavelength of light cone sensitive to (nm)
Approx 440-600

Peak wavelength Sensitivity (nm)
530

Question 44

Q

Explain that colour blindness in humans results from the lack of one or more of the colour sensitive pigments in the cones

Answer

A

Most CB→ see clearly but not fully able to see red, blue, green light

Most common; red/green→ Mix up all colours that have some red and green in colour. E.g. Confuse blue and
purple (can’t see red element of purple)

Red/green deficiencies→ murky green world→ red, brown, orange easily confused

Red/green→ from inheritance of defective allele of colour vision gene (carried on X-chromosome)

Question 45

Q

Explain why sound is a useful and versatile form of communication

Answer

A

Sound bends around objects and travels around corners→ don’t need to be visible to communicate

Travels through solids/liquids/gases

Used in dark environment and at night (E.g. Bats)

Provide directional info

On off rapid advantage

Advantage for communication of long distances→ E.g. Humpback whales; sounds produced at certain depths→ can be heard 100’s km away

Question 46

Q

Plan and perform a first hand investigation to gather data to identify the relationship between wavelengths, frequency and pitch of a sound

Answer

A

Equipment:
Cathode ray Oscilloscope (CRO), Audio oscillator/amplifier, speaker, tuning fork, sound boxes

Select wave output on audio oscillator and connect directly to CRO. Change wavelength and observe image produced

Conclusion:
Wavelength increases and pitch increases but frequency does not

If frequency decreases, amplitude stays the same

Question 47

Q

Explain that sound is produced by vibrating objects and that the frequency of sound is the same as the frequency of the vibration of the source of the sound

Answer

A

When vibrates rapidly enough for molecule movements to send compression wave through medium

Wave only travels through medium containing particles that can be compressed or spread

Frequency: Number of waves which pass a given point in 1 sec (determines pitch)

Amplitude; Max distance a particle moves away from original position (determines volume)

Wavelength: Distance between centres of 2 adjacent compressions or refractions

High freq vibrations→ high pitched sounds, short wavelengths

Low freq vibrations→ low pitched sounds, long wavelengths

Question 48

Q

What is Frequency?

Answer

A

Number of waves which pass a given point in 1 sec (determines pitch)

Question 49

Q

What is amplitude?

Answer

A

Max distance a particle moves away from original position (determines volume)

Question 50

Q

What is wavelength?

Answer

A

Distance between centres of 2 adjacent compressions or refractions

Question 51

Q

Gather and process information from secondary sources to outline and compare some of the structures used by animals other than humans to produce sound

INSECTS, FISH, MAMMALS, BIRDS

Answer

A

INSECTS
Crickets→ Produce sound by lifting wing 45° and rub front wing cover over rough other wing (Mating)

Grasshoppers→ Scrape row of pegs on back legs along hard edges of front legs

FISH
Catfish→ Vibrates bone on swim bladder→ noise similar to giant aerator bubbler on fish tank (when alarmed or travelling in shoal)

BIRDS
Use organ (syrinx) at base of trachea where bronchi branch off→ songs produced by forcing air through membranes of syrinx

Some birds mute (E.g. Pelicans, vultures)

MAMMALS
Easter horseshoe bat→ Uses nose→ emits high pitched echolocation and use area around nose to detect sound

Dolphin→ Larynx doesn’t have vocal cords→ whistles, clicks through tissue in nose→ sound from air movement in trachea and release of air in blowhole

Question 52

Q

Main functions of larynx

Answer

A

Larynx (voice box) in throat where pharynx divides respiratory and digestive tract

Main functions:
Provide open airway (when breathing)

Provide mechanism for sound production

Ensure closed air channel during swallowing→ prevents food entering trachea

Question 53

Q

Structure of larynx

Answer

A

9 cartilages joined by membranes→ form box→ holds vocal cords

Upper opening→ glottis→ covered by epiglottis (uppermost cartilage)

Epiglottis→ flexible→ tips forwards during swallowing→ prevents food entry

Thyroid cartilage→ 2 bands form Adam’s apple when joint
3 pairs smaller cartilages→ for, lateral and posterior walls (arytemoid most important→ anchor vocal cords)

Muscles connect cartilages to head or alter position, tension, shape of vocal cords

Interior→ mucous coated lining (cilia push substances towards pharynx)
Under lining→ vocal ligaments (join cartilages and draw lining up to form true cords)
True vocal cords→ vibrate and produce sound (as air passes between them)

Above true cords→ more mucous folds (false vocal cords) don’t help sound; but lubricate true vocal cords and snap shut if liquids → prevents entry to breathing passages if drinking

Question 54

Q

Phonation:

Answer

A

Process of producing intelligible sounds/speech

3 stages: production of airflow and sound and articulation of voice

Question 55

Q

Articulation of the voice

Answer

A

Vibration of vocal cords→ only produces buzzing sound

Quality of voice→ determined by other structures above larynx (pharynx and sinuses)

Sinuses→ air filled cavities lined with mucous membrane

Change in voice when person has blocked nose, sore throat

In speech→ sounds must be ‘shaped’ into vowels/consonants by tongue, cheek, lips

Question 56

Q

Production of Sound

Answer

A

Rapid opening and closing of glottis→ sets up vibration pattern (produces sound)

From release of air in lungs and vibration of vocal cords

Length of vocal cords and size of glottis→ controlled by vagus nerve→ function is contraction/relaxation of muscles→ moves attached ligaments and cartilage

Volume of voice→ controlled by strength of airflow (greater airflow; strong vibration, louder sound)

Question 57

Q

Production of airflow

Answer

A

Air expelled from lungs automatically as breathe/speak

Force of air must be great enough to push open vocal cords (by relaxing diaphragm so pressure in chest is higher than outside body)

Air forced out → to equalise air pressure inside and outside

Question 58

Q

Outline and compare the detection of vibrations by insects, fish and mammals

INSECTS

Answer

A

Receive sound and vibrations at same frequency of sound detected

Bristles on insect cuticle and antennae→ respond to low freq vibrations

Crickets→ tympanum (drum) on leg below knee→ enclosed by eardrum; nerve fibres pick up vibrations

Butterflies/moths→ Have tympani at base of wings

Pair of membranes in tympana; connected to auditory organ by short tendon at base of abdomen

Question 59

Q

Outline and compare the detection of vibrations by insects, fish and mammals

FISH

Answer

A

Hearing abilities vary between species

All fish→ Lateral line, pronounced pair of sensory organs, pair of sensory canals→ run each side of animal

Surrounding water; pressure waves→ distort sensory cells in canals→ Send message to nerves

Some fish→ sound waves by inner ear (with sensory chamber→ contains ear stone and lined with hair cells)

Auditory nerves→ detect differences in vibrations between hair cells and ear stones

Question 60

Q

Outline and compare the detection of vibrations by insects, fish and mammals

MAMMALS

Answer

A

Ear→ detect vibrations of air particles within ecosystems

Killer whale→ receive sound by lower jawbones (fat filled cavity extends back to ear-bone complex)

Sound waves received and conducted by jaw (thin, hollow bone), middle ear, inner ear and auditory nerve→ brain

Dolphins→ close ear canals when diving→ detect vibrations through head and some frequency through

Question 61

Q

Gather process and analyse information from secondary sources on the structure of a mammalian ear to relate structures to functions

PINNA/AURICLE

Answer

A

Structure:
Outer ear (with auditory canal and outer eardrum)
Either side of head (cartilage) → Low blood supply

Function:
Helps localise sound waves coming to ears

Glands in cartilage→ produce earwax (traps dust→ prevents reaching eardrum)

Relate structure to function:
Either side of head→ localise sound waves
Glands produce earwax→ protect ear

Question 62

Q

Gather process and analyse information from secondary sources on the structure of a mammalian ear to relate structures to functions

TYMPANIC MEMBRANE/EARDRUM

Answer

A

Structure: 
Taunt membrane (3 layers) → continuous with auditory canal

Function:
Airborne sound waves→ vibrations in tight membranes

Membrane grows continuously→ allows self repair after damage

Relate structure to function:
Taunt membrane→ wave vibration; response to sound

Question 63

Q

Gather process and analyse information from secondary sources on the structure of a mammalian ear to relate structures to functions

OSSICLES (BONES)

Answer

A

Structure:
3 small bones (middle ear)
Malleus; (Hammer) → lies towards side of head; ‘handle’ attached to inner layer of eardrum

Incus; (Anvil) → Attached to hammer; long process attached to stapes

Stapes; (Stirrup) → Footplate rests on oval window

Function:
When eardrum vibrates→ malleus vibrates→ passes vibrations to incus

Incoming sound given boost→ (long process of incus shorter than long process of malleus)

As incus vibrates→ footplate of stapes→ vibrating area of eardrum larger than vibrating area of stapes

Relate structure to function:
Bones vibrate and pass onto next→ sound travel

Question 64

Q

Gather process and analyse information from secondary sources on the structure of a mammalian ear to relate structures to functions

OVAL WINDOW

Answer

A

Structure:
Membrane between middle and inner ear (cover opening in cochlea case)

Function:
Separates middle ear from inner ear fluid (holds it in cochlea)

As stapes vibrates→ window vibrates→ sends waves through fluid

Relate structure to function:
Membrane separates middle ear and inner ear fluid, holds fluid in for vibrations

Answer 65

A

Structure:
Membrane; base of lower canal of cochlea

Function:
Allows release of hydraulic pressure of fluid; caused by vibrations of stapes in oval window

Relate structure to function:
Membrane allowing for release of pressure from fluid by vibrations

Answer 66

A

Structure:
3 canals filled with fluid; separated by 2 membranes

Upper canal; begins at oval window→ filled with fluid (perilymph)

Lower canal; base of cochlea→ continuous with upper canal and ends at round window

Middle canal→ contains endolymph→ separated from upper canal (Reissner’s membrane) and lower canal (Basilar membrane)

Function:
Vibration wave patterns from stapes→ set up vibration in membranes and perilymph/endolymph

Middle canal→ Holds organ of corti

Relate structure to function:
3 canals→ vibrational waves travel to membrane→ travel through cochlea

Answer 67

A

Structure:
Tectorial membrane→ covers inner and outer hair cells (outer hair→ muscle like filament. Inner hair→ Nerve fibre attached)

Basilar membrane→ Separates middle and lowest canal→ ribbon like structure; broader end towards oval window

Pillars of Corti→ Cells bind tunnel and run entire cochlear length

Function:
Sense organ of hearing→ changes mechanical energy to electrochemical energy

Sends messages to brain (vibration frequency, intensity, duration of sound)

Tectorial membrane→holds cilia of outer hair cells

Basilar membrane→ changes position in response to wave causing cilia movement

Produce sensation of hearing
High frequencies coded at end of basilar membrane (near oval window)
Low frequencies at narrow end

Relate structure to function:
Middle canal→ convert to electrochemical energy; send messages to brain→ sensation of hearing

Answer 68

A

Structure:
Leads from cochlea and organ of balance→ correct perception centre of brain

Function:
Transmits neural energy from cochlea to brain

Answer 69

A

HUMANS
Range of detected sounds (hZ) → 20-20,000

Reasons:
Basilar membrane flexibility→ limits freq range of human hearing
Evolution→ less reliance on hearing for survival
Humans→ 3D vision→ eliminates need for echolocation

DOLPHINS
Range of detected sounds (hZ) → 150-150,000

Reasons:
Dolphins can’t rely on sight all the time
High freq clicking sound→ shorter wave; used in dark waters→ locate food
Low freq sounds travel further in water→ whistles to communicate

BATS
Range of detected sounds (hZ) → 1.0- 120,000

Reasons:
Active in dawn/dusk and night→ dark→ rely on echolocation for navigation/prey
Higher freq→ more detailed messages about surroundings

Answer 70

A

HA
All ages→ some residual hearing
Success→ depends on how individual processes sound (differs for each person)

CI
Severe to profound hearing loss
No minimum age; (Youngest; 5 months. Oldest: 91 years)

Answer 71

A

HA:
Artificial device; battery operated
(5 parts) Digital sound processor, converter, amplifier, microphone, earphone

Amplifies vibrations→ physically stimulates cochlea nerves

CI:
Artificial device; battery operated
(3 parts): Headset (microphone and coil) Speech processor and the implant

Electronically stimulates cochlea nerves

Answer 72

A

HA:
Miniaturized; sits inside curve of pinna and ear canal
Worn externally

CI:
Speech processor and microphone worn externally

Implant (receiver package and electron array) surgically placed inside skull and inner ear as cochlea

Answer 73

A

HA:
Sound waves picked up by microphone→ magnified by amplifier

Channeled into auditory canal by earphone→ then normal pathway to eardrum, ossicles, cochlea, auditory nerve

CI:
Sound waves; picked up by microphone→ converted to electrical code (speech processor) → transmitted to implant

Transfers signal to electrical pulses→ stimulate cochlea nerve
Electrochemical messages to brain; decoded

Answer 74

A

HA:
Middle ear; damaged eardrum or ossicles
People with residual hearing
Sensorineural and conductive hearing loss; bypasses middle ear

CI:
Inner ear; damaged hair cells in cochlea
Bypasses eardrum, middle ear, cochlea
For totally deaf→ no benefit from hearing aids

Answer 75

A

HA:
No surgery, no side effects
Inexpensive

Programmable, background noise amplified
Distance limited to less than 3m

Doesn’t work if damage to inner ear, or auditory nerve

Used at any age
Wearer may still depend on lip reading

CI:
Requires surgery, side effects
Expensive with ongoing costs

Programming needs to be adjusted for on phone, dining with friends etc
Background noise amplified

Distance limited; effective over 15m
Deaf when not wearing

Works best before age of 5 years; harder to teach older people to interpret sounds
Wearer may still depend on lip reading

Answer 76

A

Middle ear opens in the Eustachian tube→ leads to pharynx, equalises pressure on either side of eardrum

Tube usually closed and flattened by swallowing.

Yawning opens it for sufficient time to equalise pressure between middle ear and external environment

Answer 77

A

Sound energy→ wave through air into auditory canal to outer eardrum

Kinetic energy→ vibrations from eardrum→ ossicles→ oval window
Stapes vibrate oval window→ pressure in perilymph (upper canal)

Residents membrane moves→ kinetic energy to endolymph

Vibrates basilar membrane→ stimulates hair cells in organ of Corti (send messages on nerves)

Kinetic energy now converted to electrochemical energy as info is transmitted→ nerve impulses from bakes to auditory nerve to brain

Sound emitted→ vibrating air enters outer ear [SOUND ENERGY]

Eardrum vibrates at same frequency → ossicles vibrate→ fluids in inner ear vibrate, then membranes→ tension on hair cells in organ of Corti [KINETIC ENERGY]

Neurons transfer nerve impulses to brain→ interpreted
as sound [ELECTRO- CHEMICAL ENERGY]

Answer 78

A

Organ of Corti→ On top of basilar membrane (made of supporting cells and 15,500 hearing receptor cells- cochlea hair cells)

Not replaced as they die. One row of inner hair cells and 3 outer rows

Fibres of cochlea nerve coiled around bases of hair cells

Activation of hair cells at points of high vibration of basilar membrane

Hair cells at base (oval window) stimulated by high pitch sound. At narrow end of cochlea (apex) need low pitched sound

Inner hair cells responsible for sending most of auditory messages to brain

Answer 79

A

Noise coming from right→ reaches right ear first

To reach left ear→ must travel around head or through
head

Head absorbs high frequencies easier than low→ causes sound shadow cast over ear furthest away from sound source

Sound shadow enables humans to determine direction of the sound

Answer 80

A

No neurons exactly alike, but all have three parts: Cell body, dendrites (extension that conduct nerve impulses to cell body) and axon (extension that conducts impulses away from cell body)

Nerve fibres transmit info rapidly along entire length, pass onto successive neurons

Dendrites, axons → fluid filled tubes, surrounded by fatty insulating layer (myelin sheath)
Myelin sheath: built as layers, supported by Schwann cells on outside

Cell body of neuron→ usually in brain or spinal cord→ axons/densities extend towards organ

Ion channels function in action potential→ concentrated in node regions of axons

Action potential jumps from node to node→ skips insulated region in membrane between node

If impulse travels from sensory organ to CNS→ dendron called sensory fibre

If impulse passes from CNS to muscle or gland→ axon called motor fibre

Answer 81

A

Sensory neurons→ Transmit impulses from sense organs to other neurons in CNS

Motor neurons→ Transmit impulses from CNS to muscles and glands

Connector neurons→ Connect sensory and motor, (usually in brain/spinal cord)

Answer 82

A

Cell body is central structure with neuritis (long, thin structures) radiating outwards from it

Neurone→ term for processes connecting nerve cells together to form network of nervous tissue

Can be either receiving (dendrites) or transmitting (axon) nerve impulses

Answer 83

A

Nerves transmit signals along neuronal membranes and by chemicals from one neuron to next

Answer 84

A

Body is electrically neutral (same number of positive and negative charges)

Potential difference: Voltage measured between 2 points; exists across every cell plasma membrane

Side of membrane exposed to cytoplasm (negative)

Side exposed to extracellular fluid (positive)

Differences on either side → cellular voltage (resting potential→ -70mV) indicates inside if membrane is negative (polarised)

Occurs due to neurons containing ions (charged particles)

Membranes selectively permeable to Na+ and Cl- (due to ion channels)

When ion channel pores open→ ions move from one side of membrane to other

Each channel→ allows only a specific type of ion to diffuse through it

Answer 85

A

Changes in neurone environment→ can affect permeability of plasma membrane to ions→ changes membrane potential

Cell membrane potential can change in response to stimulation→ A positive shift in membrane potential from -70mV to -40mV→ called depolarisation

If depolarization strong enough→ flow causes ions to generate nerve impulse (action potential)

Action potentials→ transmitted from neurone to neurone across synapses (small gaps between end of axon and dendrites) → movement in 1 direction only

At synapse→ neurotransmitters diffuse across gap from one neurone membrane of receiving neurone→ causes electrical response

Answer 86

A

Sheep dissection; label pins onto the regions. Then dissect the brain in half and identify grey matter

Answer 87

A

Mass of wrinkled tissue(makes up 90% of brain)

Responsible for complex thoughts, senses, muscle control, memory, thinking

Answer 88

A

“Stem” of brain

Controls activities not requiring conscious thought (Breathing, heartbeat)

Answer 89

A

“Base” of brain

Controls complex muscle movements (cycling, running, walking)

Answer 90

A

Threshold: Amount of positive charge in membrane potential required before action potential produced

Depolarisation: Must reach a threshold at least 15 mV more positive than resting potential (-70mV) → No action potential produced if depolarisation below this level

Each stimulus produces either full action potential, or none at all

Each one is separate event→ a cell can’t produce another until previous is complete

Answer 91

A

Split into 2 hemispheres (left and right) → divided into 5 lobes

Each hemisphere receives impulses and exerts control over opposite body side

Under tough protective covering, surface drawn into folds→ triples surface area

Most of activities occur on outer surface (in layer of grey matter)

Activities: 3 categories: Motor (movement) sensory (senses) and associative (reason and logic)

Answer 92

A

Optic nerve→ sensory vision nerve, pass through skull via opening in eye socket

Nerves from each eye→ partly cross over to form optic cross: provide each visual cortex with same image, (but each eye receives image at slightly different angles)

Visual cortex in occipital lobe of each cerebral hemisphere

Auditory nerves→ from cochlea and vestibule in inner ear→ merge to form one nerve (vestibulocochlear)

From organ of Corti to auditory cortex in temporal lobe in each cerebral hemisphere

Answer 93

A

Stimuli must be received and transmitted to brain before being interpreted and response

Variety of reasons can cause ‘short circuit’
Lack of stimulus z(e.g. Cataracts, ear canal blockage)

Trauma (E.g. Severing or damage to nerves, concussion)

Lack of oxygen (asphyxiation, stroke)

Legal/illegal drug reaction (alcohol, anaesthetic, sedatives)

Age related or deterioration

Answer 94

A

Autoimmune disease→ immune attack by body on own myelin protein

Gradually myelin sheath destroyed

Insulating layer non functional→ impulses short circuited, impulse stops

Common symptoms: Problems controlling muscles

Answer 95

A

All impair message transmission→ block nerve impulses (reduce plasma membranes permeability to sodium ions)

If no sodium entry→ no action potential→ no nerve impulse

Common symptoms: Poor coordination, tiredness, blurred vision and speech, retarded reflexes

Answer 96

A

Caused by: Temporary lack of oxygen to a baby during difficult delivery

Voluntary muscles lack coordination due to brain cell damage

Brain cells can’t transmit message to muscles→ muscles can’t be controlled

Common symptoms: Movement, speech, hearing,mission impairments

Answer 97

A

2 types: NF1 and NF2→ both genetic disorders: tumours grow along various nerves

NF1
Common symptoms: Coffee coloured birthmarks and tumours in or under skin
Tumours may develop on brain, spinal cord (learning difficulties)

NF2
Much rarer, multiple tumours on nerves of spine and brain
Common symptoms: Hearing loss in teens (tumours affecting auditory nerve)

Answer 98

A

Caused by rubella virus→ causes rash, fever, some respiratory tract infection (no more than common cold)

Women contract in 1st 3 months of pregnancy→ virus may pass onto developing baby

Damage to brain and spinal cord→ lack of transmission of nerve signals to organs

Baby could be affected by rubella congenital syndrome (RCS)

Common symptoms of RCS
High rubella antibody level, cataracts, hearing loss, problems with development of spinal cord, spleen, liver, bones

Answer 99

A

Human brain→ reaches max size in young adulthood→ after: neurons may die or be damaged→ contributed to gradual loss of weight and brain volume

In total→ change is minimal

Common symptoms
Decline in reaction time and speed of decision making
Some memory loss

Brainscape's Knowledge GenomeTM

Option: Communication Flashcards

Brainscape's Knowledge Genome^TM