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Flashcards in Science 3 Deck (46):

What are the two main parts of the central nervous system?

The brain and the spinal cord


What is the name for the special nerve endings in your skin that can detect stimuli? Give an example of one of these special nerve endings.

Receptors, Thermoreceptors


List 4 types of stimuli

Light, sound, chemical, pressure, heat, smell


What type of message is passed down the axon and what is it caused by?

An electrical impulse is passed down the axon and is caused by a change in the ion concentration outside and inside a neuron, as a result of a stimulus.


Why does one neuron have so many branches at the axon terminal?

So the message is given to all the fibres in a muscle so it will move at the same time


What is a neurotransmitter and what function does it have?

It is a chemical molecule that passes the electrical message from one neuron to the next through synapses', or from the neuron to the muscle cells


What is the function of the myelin sheath?

To insulate the axon and enable the message to move quicker


Why does the message go to the brain only after a reflex response has occurred?

It first goes to the spine so that the response to the stimulus happens very quickly to prevent any further damage


Explain the difference between the autonomic and somatic nervous system

The Somatic system(SNS) is voluntary whilst the Autonomic system (ANS) is involuntary


Explain the “flight or fight” response in terms of some aspect of the sympathetic / parasympathetic nervous system

An increase in heart beat (sympathetic) in preparation for fight or flight, followed by a decrease in heartbeat as the body returns to normal (parasympathetic).


In the dissection of the sheep brain, there is a clear difference between gray and white matter. Explain what gray and white matter is.

Gray matter on the outer surface is composed of neuron cell bodies whilst white matter is the axon fibres.


Explain the function of the cerebrum

The Cerebrum is the largest part of the brain. It is also known as the cerebral cortex. It helps you talk, hear, feel, think, see, smell and taste


Explain the function of the cerebellum

The Cerebellum controls movement of different parts of the body and controls your balance.

Injury or damage to the cerebellum can cause you to lose control of your arms, legs, and other moving parts of your body.


Explain the function of the brain stem

The Brain Stem connects the brain to the spinal cord. The nerves in the brain stem 
control your heartbeat, breathing, and blood pressure


Why is the cerebrum so wrinkly?

To increase the number of neurons that can fit in the brain


What are the four lobes of the brain?

Frontal, parietal, occipital and temporal (FPOT)


Frontal lobe

It's associated with reasoning, motor skills, higher level cognition, and expressive language. At the back of the frontal lobe lies the motor cortex. This area of the brain receives information from various lobes of the brain and utilizes this information to carry out body movements.


Parietal lobe

middle section of the brain and is associated with processing tactile sensory information such as pressure, touch, and pain. A portion of the brain known as the somatosensory cortex is located in this lobe and is essential to the processing of the body's senses


Occipital lobe

back portion of the brain and is associated with interpreting visual stimuli and information. The primary visual cortex, which receives and interprets information from the retinas of the eyes, is located in the occipital lobe.


Temporal lobe

bottom section of the brain. This lobe is also the location of the primary auditory cortex, which is important for interpreting sounds and the language we hear. The hippocampus is also located in the temporal lobe, which is why this portion of the brain is also heavily associated with the formation of memories


What part of the brain was affected in Phineas Gages accident?

Frontal Lobe


The brain is divided in two halves called..

...cerebral hemispheres


The ....... is the white bridge that connects the two parts of the brain.

Corpus callosum


Sensory memory provides you with an awareness of where you are in relation to objects and the space around you. How long does sensory memory last for and where is this information stored?

20 seconds and the cerebral cortex


When remembering information we often use a process called chunking. What is this process?

Grouping numbers or letters together and giving them some meaning


What is Homeostasis?

A maintenance of constant environment that your cells live in ex. Ph levels


Identify two differences between the nervous system and the endocrine system

Hormonal system (slower and involves chemical messages, the circulatory system (bloodstream) and is longer lasting) Whilst the Nervous system (faster, involves electrical and chemical messages, is short acting)


What does the exocrine gland do?

Exocrine gland secretes products into a duct (such as saliva, digestive enzymes, tears)


What does the endocrine gland do?

Endocrine gland secretes hormones into the bloodstream (such as adrenaline, insulin)


Adrenaline binds to receptors in both the heart and the muscle. What name do we give to these cells?

Target cells


When adrenaline is released the heart will beat faster and the muscles will get ready to contract. Why do they have this response?

Preparation for 'Fight or Flight'


What hormones does the pancreas create?

Insulin and Glucogen


When insulin regulates the level of glucose in the blood steam by making muscles absorb it does it raise or lower the level of glucose?



When the hormone, Glucagon, causes the glycogen to break down what is released and does it increase or decrease blood glucose levels?

Glucose increases


In the stimulus response model, an increase of blood glucose results in the production of insulin and the effect is a lowering of blood glucose as the liver takes up the glucose. Is this an example of positive or negative feedback?

Negative feedback


If you had just eaten a huge piece of chocolate cake would your blood sugar levels indicate hypoglycaemia or hyperglycaemia?



What are some of the symptoms of hyperglycaemia?

Thirst, increase of urination


What would you give a person who had hypoglycaemia?

Sugar, soft drink or jelly beans usually


Does a person with Juvenile Diabetes have very high or very low levels of insulin?



What might be one of the long term effects on a person’s body as a result of diabetes?

Blindness and poor circulation which may lead to amputation


What is the master gland in the brain that controls all other glands – the pituitary or the thyroid gland?

Pituitary gland


What is the Sympathetic nervous system?

Fight or flight response


What is the Parasympathetic nervous system?

Rest and digest


What is the negative feedback system?

Negative feedback reactions are those in which the response is in the opposite direction to the stimulus


Why is glucose stored in the muscles and liver?

For a quick response or fight or flight. It provides a ready source of fuel for the muscles and the liver is close to the heart which requires fuel to beat faster when in the sympathetic nervous system


What is R-SIM?

R - receptors receive stimuli S - sensory neuron passes on the information I - inter neuron process M - motor neuron acts