Biopsychology Flashcards
(56 cards)
Define endocrine system
One of the body’s major information systems that instructs glands to release hormones directly into the blood stream. These hormones are carried towards target organs in the body.
Define gland
An organ in the body that syntheses (makes) substances such as hormones.
Define hormone
Chemical substances that circulate in the bloodstream and only affect target organs. They are produced in large quantities but disappear quickly. Their effects are very powerful.
Define adrenaline
A hormone produced by the adrenal gland which is part of the body’s immediate stress response system. Has a strong effect on the cardiovascular system - e.g., stimulating heart rate.
Define the fight or flight response
The way animal responds when stressed. The body becomes physiologically aroused in readiness to fight an aggressor or in some cases flee
Define nervous system
Consists of the central nervous system and the peripheral nervous system.
Define central nervous system ( CNS )
Consists of the brain and the spinal cord and is the origin of all complex commands and decisions. It passes messages to and from the brain and connects nerves to the PNS.
What is the brain?
The centre of all conscious awareness. The cerebral cortex is highly developed in humans and is what distinguished our higher mental functions from those of animals.
What is the spinal cord?
An extension of the brain. It is responsible for reflex actions such as pulling your hand away from a hot plate.
Define Peripheral nervous system (PNS)
Sends information to the CNS from the outside world and transmits messages from the CNS to muscles and glands in the body. It does this via millions of neurones (nerve cells) and is divided into the ANS and SNS.
Define somatic nervous system
Transmits information from receptor cells in the sense organs to the CNS. It also receives information from the CNS that direct muscles to contract. Controls muscle movement and receives information from sensory receptors.
Define autonomic nervous system
Transmits information to and from internal bodily organs.
It is ‘autonomic’ as the system operated involuntarily. It has two main divisions: the sympathetic and parasympathetic nervous systems. Governs vital functions of the body such as breathing, heart rate, digestion, sexual arousal and stress responses.
Define parasympathetic nervous system
A decision of the ANS which controls the relaxed state ( rest and digest) conserving resources. Opposition to the sympathetic nervous system
Define the sympathetic nervous system
A division of the ANS which activates internal organs for vigorous activity’s and emergencies such as the fight or flight. It has nerves which control increases heart rate and breathing.
Define neurones
The basic building blocks of the nervous system, they are nerves cells that process and transit messages.
What are sensory neurones?
They carry messages from the PNS to the CNS. they have long dentrites and short axons.
What are relay neurones?
They connect the sensory neurones to the motor or other relay neurones. They have short dendrites and short axons.
What is a motor neurone?
They connect the CNS to effectors such as muscles and glands. They have short dendrites and long axons
Define cell body
This is known as the factory of the neuron and it contains the nucleus N produced all of the necessary proteins that a neurone requires to function
Define nucleus
This contains the genetic material within the neurone
Define dendrites
The branch like features protrude from the cell body. They carry nerve impulses from neighbouring neurones toward the cell body.
Define nodes of Ranvier
They are the gaps between the myelin sheaths. They help to speed up the transmission of the impulse
Define axon
This carried the electrical impulse from the cell body down the length of the neurone. It is covered in myelin sheath.
Define myelin sheath
This is a fatty layer which surrounds and protects the axon it helps speed up the electrical transmition
