Term 4 - Biology

Question 1

Identify the five senses and the sense organs associated with each type of stimuli:

Answer 1

Sight – Eye (responds to light stimuli)
Hearing – Ear (responds to sound waves)
Touch – Skin (responds to pressure, temperature, and pain)
Taste – Tongue (responds to chemical stimuli in food)
Smell – Nose (responds to chemical stimuli in the air)

Question 2

Identify key structures within the ear:

Answer 2

Pinna, Auditory Canal, Ear Drum, Hammer, Anvil, Stirrup, Semicircular Canals, Cochlea, Auditory Nerve

Question 3

Identify key structures within the eye:

Answer 3

Pupil, Iris, Lens Cortex, Cornea, Ciliary Muscle, Retina, Sclera, Optic Nerve

Question 4

Describe the structure of the ear and explain the steps involved in the detection of sound:

Answer 4

Soundwaves from outside enter the ear from the Pinna and move into the Auditory Canals that amplify sound. Then the sound hits the ear drum, causing the hammer, anvil and stirrup to vibrate, converting the waves into mechanical vibrations. Next is the Cochlea that converts the vibrations into electrical signals by tiny hair cells. Then the Auditory Nerve carries the electrical signals to the brain.

Question 5

Describe the structure of the eye and explain how these function together to detect light:

Answer 5

Light enters the cornea and passes through the pupil.
The lens focuses light onto the retina, where photoreceptor cells (rods for low light, cones for color) detect light.
These cells convert light into electrical signals that travel through the optic nerve to the brain, where images are processed.

Question 6

Describe the structure of a typical neuron

Answer 6

Soma (cell body), nucleus, dendrites, axon (Scwann cell, node of Ranvier and myelin), and axon terminal

Question 7

Describe the passage of information through a neuron, across the synapse, and to the next cell:

Answer 7

Dendrites receive electrical signals from other neurons, bringing information into the cell body, then the electrical signals are carried through the axon away from the cell body and end up at the axon terminal. Then, neurotransmitters are released from the axon and cross the synapse where they bind to receptors on the next neuron or cell. This triggers a new electrical signal in the next cell, allowing the message to continue.

Question 8

Explain the stimulus-response model using an example:

Answer 8

EXAMPLE TOUCHING A HOT SURFACE
Stimulus - heat detected by receptors in the skin
Receptor - skin receptors generate an impulse
CNS - the impulse is sent to the spinal cord/brain
Effector - muscles in the hand contract
Response - hand pulls away from heat

Question 9

Explain how reflex actions provide responses:

Answer 9

Reflexes are automatic fast responses to certain stimuli, often to protect the body from harm.
Reflexes don’t need the brain to process the information, instead the message goes through the spinal cord, allowing for immediate reaction.

Question 10

Describe the role of the CNS

Answer 10

The central nervous system includes the brain and spinal cord and processes all the information your body receives and sends out. The brain is the control center while the spinal cord acts as a pathway for messages.

Question 11

Describe the role of the PNS

Answer 11

The peripheral nervous system includes all the nerves outside the CNS. It connects the CNS to the rest of the body allowing communication between the brain, muscles, skin and organs

Question 12

Describe the role of the somatic nervous systems:

Answer 12

Controls voluntary movements (e.g. walking) and send messages from CNS to skeletal

Question 13

Describe the role of the autonomic nervous systems:

Answer 13

Control involuntary processes (e.g. heartbeat) and operate automatically without your conscious control

Question 14

Identify the lobes of the brain

Answer 14

Frontal Lobe, Temporal Lobe, Parietal Lobe, Occipital Lobe

Question 15

Role of Frontal Lobe

Answer 15

Control Panel for your personality, communication, spontaneity, judgement, impulse, language and memory

Question 16

Role of Temporal Lobe

Answer 16

Process things you hear into things that make sense, responsible for object recognition and long-term memories

Question 17

Role of Parietal Lobe

Answer 17

Interprets senses and visuals, processes language and math, responsible for spatial awareness and navigational skills

Question 18

Role of Occipital Lobe

Answer 18

All about visual processing and spatial perception, colour and movement

Question 19

Role of Cerebellum

Answer 19

Helps motor skills by controlling coordination, balance and timing

Question 20

Role of Brain stem

Answer 20

Links the cerebrum to the Cerebellum controls the nerves going to the face and neck and controls involuntary processes

Question 21

Role of Spinal cord

Answer 21

Is a highway of nerves connecting the brain to the rest of the body

Question 22

Define homeostasis and recognize why this is important:

Answer 22

Homeostasis is the process of keeping the body’s internal environment stable. This is important as without it, enzymes and cells could stop working

Question 23

Describe key structures in the endocrine system such as the pituitary gland and their role in homeostasis:

Question 24

Compare a hormonal response and a nervous response to a stimulus:

Question 25

Describe the process of how negative feedback loops work using examples:

Question 26

Apply the concept of homeostasis, hormones, and negative feedback loops to explain:

Control of Blood Glucose Level

Question 27

Apply the concept of homeostasis, hormones, and negative feedback loops to explain:

Control of Internal Body temperature

Question 28

Apply the concept of homeostasis, hormones, and negative feedback loops to explain:

Control of Water Content