Detection and Response (CH 40, 42, 43)

Question 1

What is the name of the light sensing protein?

What is this responsible for?

Answer 1

phytochrome

plant growth responses

Question 2

What are the three plant growth responses?

Answer 2

1. ) seed germination
2. ) shoot elongation
3. ) detection of plant spacing

*look at slide for red light vs. far red light associations

Question 3

the bending of growing stems to sources of light with blue wavelengths (460-nm range) is associated with what?

Answer 3

phototropin

Question 4

which cells sense gravity?

Answer 4

endodermal cells

Question 5

how do plants move?

Answer 5

cell surface proteins, water potential, and plant hormones

Question 6

What are the 5 plant movements?

Answer 6

Photomorphogenesis
Thigmomorphogenesis
phototropism
thigmotropism
gravitrophism

Question 7

What is Photomorphogenesis?

Answer 7

permanent light-triggered development

Question 8

What is Thigmomorphogenesis?

Answer 8

permanent touch triggered responses

Question 9

What is phototropism?

Answer 9

directional growth responses to light

Question 10

What is Thigmotropism?

Answer 10

directional growth responses to mechanical stimuli

Question 11

What is Gravitrophisms?

Answer 11

directional growth responses to earth’s gravity

Question 12

touch induced plant movements involve reversible changes in what?
What is another name for these cells?

Answer 12

turgor pressure

pulvini

Question 13

What are examples pf touch related turgor?

Answer 13

snapping of the venus flytrap

curling of tendrils

Question 14

What is an example of a plant that undergoes light related turgor?

Answer 14

bean leaves

Question 15

what are the two types of gravitropism and give an example

Answer 15

negative = shoots
positive = roots

Question 16

what is responsible for the curvature of stems upwards and asymmetrical cell elongation?

Answer 16

Auxin

Question 17

what is abscission?

Answer 17

when a plant drops its leaves or petals to conserve resources

Question 18

True or False:

in plants hormones are produced by specialized tissues?

Answer 18

False

Question 19

one of the effects of auxin is an increase in__________

Answer 19

plasticity of the plant cell wall

Question 20

What do cytokinins do?

Answer 20

stimulate cell division and differentiation

Question 21

there is a plant pathogen called Agrobacterium that introduces genes into the plant genome that increase the production of cytokinins and auxins. What does this cause in the plant?

Answer 21

massive cell division and formation of a crown gall tumor

Question 22

Whats the name of the 100+ naturally occurring plant hormones?

Answer 22

gibberellins

Question 23

what do gibberellins do?

Answer 23

hasten seed germination

*used commercially to extend the internode length in grapes resulting in larger grapes

Question 24

what does ethylene do?

Answer 24

retards growth

• suppresses stem and root elongation
• controls lead, flower, and fruit abscission
• hastens fruit ripening

Question 25

True or False: | Abscisic Acid counteracts gibberellins and auxin

Answer 25

true

Question 26

Why is Abscisic Acid important? | 2 things

Answer 26

necessary for dormancy in seeds and important in opening and closing the stomata

Question 27

Animal responses to the environment involve which three systems?

Answer 27

Endocrine, Sensory, Nervous

Question 28

What do exteroceptors do?

Answer 28

sense external stimuli | ie: smells, taste

Question 29

What do Interoceptors do?

Answer 29

sense internal stimuli | ie: temperature, pH

Question 30

what stimulates mechanoreceptors?

Answer 30

mechanical forces such as pressure

Question 31

What do chemoreceptors do?

Answer 31

detect chemicals or chemical changes

Question 32

What do energy-detecting receptors do?

Answer 32

react to electromagnetic and thermal energy

Question 33

Sensory cells respond to stimuli via _________ in their membranes

Answer 33

stimulus-gated ion channels

Question 34

There are 5 specific mechanoreceptors that we need to know for this exam. What are they?

Answer 34

``` Nociceptors Thermoreceptors Proprioceptors Baroreceptors Sensory Hair cells ```

Question 35

Describe Nociceptors

Answer 35

- transmit impulses based on cell damage - perceived as pain - mostly free nerve endings

Question 36

Describe Thermoreceptors

Answer 36

- naked dendritic endings of sensory neurons - sensitive to changes in temperature - contain ion channels that are responsive to hot and cold - Cold receptors are located higher in the skin, and are much more numerous than warm receptors

Question 37

Describe Proprioceptors

Answer 37

- monitor muscle length and tension | - provide information about the relative position or movement of animal's body parts

Question 38

Describe Baroreceptors

Answer 38

- monitor blood pressure - branched network of afferent neurons in the carotid sinus and aortic arch - detect tension or stretch in the walls of these blood vessels

Question 39

Describe Sensory Hair cells

Answer 39

- specialized cells named stereocilia that have cytoplasmic extensions - when they bend, stereocilia send action potential to a sensory neuron - responsible for several senses including water current, hearing, and balance

Question 40

explain the lateral line system in fish

Answer 40

- Canals run the length of the fish's body beneath the skin surface - contain hair cells in a gelatinous cupula - innervated by sensory neurons that transmit impulses - bending of stereocilia detects currents

Question 41

What is hearing?

Answer 41

the detection of vibrations that is perceived as sound | involves stereocilia

Question 42

What are the advantages of hearing?

Answer 42

- auditory stimuli travel farther and faster than chemical ones - auditory receptors provide better directional information than chemoreceptors

Question 43

describe how sound is interpreted via the cochlea (organ of Corti)

Answer 43

- Has a basilar membrane with hair cells - vibrations of the basilar membrane's hair cells press the stereocilia against the tectorial membrane - send serve impulses to the brain where they are interpreted as sound

Question 44

A few mammals have the ability to perceive presence and distance of objects by sound. What is this called? Give an example of an animal that does this.

Answer 44

Echolocation | bat, shrews, whales, dolphins

Question 45

In vertabrates, the gravity receptors consist of two chambers in the membrous ______

Answer 45

labyrinth **look over balance and acceleration slide (40-42)

Question 46

Chemoreceptors are responsible for what?

Answer 46

our sense - taste - smell - blood composition

Question 47

What is the act of tasting called?

Answer 47

Gustation

Question 48

what are the five receptor types of taste?

Answer 48

sweet, sour, salty, bitter, and umami (glutamate)

Question 49

collections of chemosentitive cells associated with afferent neurons are known as what?

Answer 49

taste buds

Question 50

The act of smelling is called what?

Answer 50

olfaction

Question 51

smell involves what?

Answer 51

neurons located in the upper portion of the nasal passages

Question 52

How many smell receptors do humans have? | How many smells can we discern?

Answer 52

400 | trillion

Question 53

Peripheral chemoreceptors and central chemoreceptors have to do with what?

Answer 53

pH | *look at slide 47

Question 54

Vision begins with the capture of light energy by _________

Answer 54

photoreceptors

Question 55

Many invertebrates have photoreceptors clustered in an_______

Answer 55

eyespot

Question 56

What are the four phyla that have developed image forming eyes?

Answer 56

annelids, mullusks, arthropods, chordates

Question 57

The vertebrate retina contains two types of photoreceptors. What are they and describe them

Answer 57

Rods: black and white vision when illumination is dim Cones: color vision and high visual acuity (sharpness) -most are located in the central region of the retina

Question 58

What photopigment do rods have? | What photopigment do cones have?

Answer 58

rods have rhodopsin cones have photopsin *each has a different amino acid sequence

Question 59

Carnivores have 2 types of cones and are called______ Humans have 3 kinds of cones and are called______ Birds have 4 kinds of cones and are called______

Answer 59

dichromats trichomats tetrachromats

Question 60

What can birds see that we can't?

Answer 60

ultraviolet

Question 61

______ a transparent structure that completes focusing of light onto the______

Answer 61

lens; retina

Question 62

What is the only vertebrate that can sense infrared radiation? What does it help them do?

Answer 62

snakes (have pit organs on either side of the head) | locate heat sources in the environment (prey in darkness)

Question 63

Elasmobranchs (sharks, rays, skates) have electroreceptors that makes them able to do what?

Answer 63

sense electrical currents generated by the muscle contractions of their prey **(Ampullae of Lorenzini)

Question 64

What is magnetoception?

Answer 64

a sense which allows an organism to detect the magnetic field lines of the Earth -explains how birds migrate

Question 65

The nervous system links which 2 things?

Answer 65

sensory receptors and motor effectors

Question 66

What does the central nervous system consist of?

Answer 66

spinal cord and brain

Question 67

What does the peripheral nervous system consist of?

Answer 67

sensory and motor neurons

Question 68

Which phylum doesn't have nerves?

Answer 68

sponges

Question 69

Cnidarians have the simplest nervous system. Describe it

Answer 69

neurons are linked to each other in a nerve net - no association neurons - one big reflex machine

Question 70

almost all other nervous systems of invertebrates are similar to that of the platyhelminth model. What are 3 characteristics of this model?

Answer 70

- 2 nerve cords run down the body - permit complex muscle control - rudimentary 'brain'