B1: Irritability in Animals and Plants Flashcards
definition of a stimulus
a change in the environment of an organism that causes a response
define a response
the change the whole or part of an organism as result of a stimulus
what is a receptor
the part of an organism that detects a stumulus
what is an effector
the part of an organism that responds to a stimulus
what are sense organs?
organs that contain receptors
Parts of the nervous system
There are (1)_________ types of neurones. These are: (2)____________, (3)_______________, (4)_________________. The (5)___________ are only found in the CNS.
- 3
- sensory
- relay(intermediate) neurones
- motor neurones
- relay
what kind of neurone is this?
name the parts
sensory neurone
A. cytoplasm
B. cell body
C. sensory nerve endings
D. nerve ending
E. node of Ranvier
F. dendrite
G. myelin sheath
H. axon
what kind of neurone is this?
name the parts
motor neuron
A. nerve endings
B. cell body
C. myelin sheath
D. Axon
E. axon fibre
F. muscle
G. nerve endings
what does this diagram show?
name the parts
reflex arc
A. receptor
B. stimulus(eg. hot surface)
C. response(withdrawal)
D. sensory nerve fibre(axon)
E. effector(muscle)
F. spinal nerve
G. motor nerve fibre
H. synapse
I. Intermediate neurone
J. cell body of
What are the functions of the cerebellum?
- receives information from balance receptors in the ear and from stretch receptors in muscles and tendons.
- coordination of balance, posture and movement
what are the functions of the cerebrum?
- conscious thought, problem solving, decision making, intelligence and emotions
- memory, speech , language and hearing
- interpretation of sensory information from sense organs
- coordination of voluntary actions
what are the functions of the medulla oblongata?
constrols involuntary actions such as:
- rate and depth of breathing
- heart rate
- blood pressure
- peristalsis
what is the function of the hypothalamus?
- controls body temperature
- controls water content of the blood
- controls the release of hormones from the pituitary gland: ADH (to control the kidney), FSH and LH(control mentral cycle)
a. what kind of neurone is this?
b. what does the arrow represent?
a. intermediate(relay) neurone
b. direction of the nerve impuse
name the neurones
- sensory neurone
- intermediate (relay) neurone
- motor neurone
what are the functions of the labelled sections below?
- sensation
- muscle control
- sight centre
intentify the parts of the nervous system
- central nervous system
- Peripheral nervous system
A. cerebrum
B. cerebellum
C. medulla oblongata
D. spinal cord
E. cranial nerves (from eye and ear)
F. spinal nerves
G. sensory and motor nerve fibres to and from body
H. brain
complete the flow diagram below
stimulus —> receptor —> sensory neurone
—> intermediate neuron —> motor neurone
—> effector —> response
how movement in parts of plants occur
by changes in turgidity of its cells
shoots grow and bend towards (1)_________ and away from (2)___________. If there is no light (eg. dark room) or even distribution of light they will grow (3)____________.
- light
- gravity
- upwards
roots bend towards (1)_____________ and (2)______________
- gravity
- water
what is a synapse?
tiny gap between the synaptic knobs of an axon and the dendrites or cell body of adjacent neurones
how do synapses work?
when the impulse reaches the nerve ending, chemicals called neurotransmitters are released and diffuse across the synapse toward the next neurone which is stimulated to transmit the electrical impulse
function of the synapse
allows neurotransmitter to flow in one direction from one neurone to another
examples of sense organs in animals
eyes, ears, tongue, nose, skin
examples of effectors in animals
muscles and glands
most plant responses are (1)_____________ and are regions of the plant where growth occurs called (2) ____________
- Growth repsonses
- Apical meristems
examples of effectors in plants
petioles, leaves, apical meristem
What is the apical meristem
The apical meristem is the region of dividing cells located at the tips of a plant’s shoots and at the ends of the plant’s roots?
what is a petiole?
the stalk that attaches the leave blade to a stem
where are nerve impulses transitted?
through neurones
what are nerve impulses
electrical impulses that travel along a neurone
CNS consists of:
brain and spinal cord
PNS consists of :
cranial nerves and spinal nerves
the function of the sensory neuron is to (1)____________ while that of the motor neurone is to (2)_______________. The relay neurone is also known as the (3)___________ and serves to (4)______________
- transmit nerve impulses from the receptors to the CNS
- transmit nerve impulse form the CNS to the effector
- intermediate neurone
- link sensory and motor neurones
what is a reflex action?
a rapid, automatic involuntary response to a stimulus by a muscle or gland
3 examples of reflex action
- withdrawal of hand when it touches a hot object
- knee jerk reflex
- reaction of the pupil to bright light
two functions of the myelin sheath are:
- protect the nerve fibre
- insulate the nerve fibre
- speed up transmission of impulses
(1)_______ carry impulses toward the cell body and (2)________ carry nerve impulses away from the cell body
- dendrites
- axons
this part of the neuron carries impulses toward the cell body
dendrite
this part of the neuron carries impulses away from the cell body
axon
identify the main regions of the human brain from the diagram
A- cerebrum
B- cerebellum
C- medulla oblongata
definition of a drug
a chemical substance that affects the functioning of the body
what is the effect of alcohol on the nervous system?
it is a depressant of the central nervous system
short term effects of alcohol abuse include:
- impaired coordination
- impaired concentration
- impared judgement
- blurred vision
- slurred speech
- memory lapse
- drowsiness
- dehydration
- loss of consciousness
some long term effects of alcohol abuse include:
- long term memory loss
- high blood pressure
- heart disease such heart attacks
- stroke
- stomach ulcers
- liver disease such as cirrhosis and fatty liver disease
- brain damage
- cancer of the mouth throat and oesophagus
- delirium tremens
what is the effect of cocaine on the CNS?
it is a stimulant
some effects of cocaine abuse
- paranoia, anxiety and depression
- bizzzare, erratic violent behavior
- hallucinations
- insomnia
- heart attack
- stroke
- lung damage
- mental disorders such as schizophrenia
the eye detects (1)_______ that has been reflected from an object and converts it to (2)__________ which are then carried along the (3)__________ to the (4)___________ which translates them into a precise image of the object
- light
- nerve impulses
- optic nerve
- brain
indentify the parts of the eye below
A- iris
B- pupil
C- cornea
D- lens
E- suspensory ligament
F- ciliary body
G- vitreous humour
I - sclera
II - choroid
III - retina
IV - fovea
V - optic nerve
the two main photoreceptors of the retina are:
- cones
- rods
the retina is composed of receptors called (1)___________ which are of two types: (2)______________ function in low light and and detect images in (3)__________. (4)_________ function in bright light and and detect images in (5)______________ and detail.
- photoreceptors
- rods
- black and white
- cones
- colour
what is accomodation?
changing the shape of the lens to focus light on the retina
The (1)___________controls the amount of light entering the eye by (2)__________. In bright light the (3)____________ relaxes and the (4)_________ contract, thus (5)________ the pupil size. In dim light the circular muscles (6)_________and the radial muscles (7)_________ contract, thus (8)________ the pupil size.
- pupil
- increasing or decreasing its size(diameter)
- radial muscles
- circular muscles
- reducing
- relaxes
- contract
- increasing
myopia or hypemetropia?
myopia
myopia or hypermetropia?
hypermetropia
what condition is being corrected?
hypermetropia (far sight)
what condition is being corrected?
myopia(near sight)
what type of lenses correct these conditions
- hypermetropia
- myopia
- covex or converging
- concave or diverging
