Option A: A.2 The Human Brain Flashcards Preview

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Flashcards in Option A: A.2 The Human Brain Deck (65):
1

Neurogenesis

the growth and development of nervous tissue.

2

Neural tube

(in an embryo) a hollow structure from which the brain and spinal cord form

3

Forebrain

the front part of the three primary divisions of the brain of a vertebrate embryo

4

Cerebral hemispheres

Either of the two symmetrical halves of the cerebrum. They are associated with intelligence, personality, sensory impulses, motor function, organization and problem solving

5

Cerebrum

the main portion of the brain, occupying the upper part of the cranial cavity; its two hemispheres, united by the corpus callosum, form the largest part of the central nervous system in humans.

6

Synapse

a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.

7

Hypothalamus

Maintains homeostasis, coordinating the nervous and the endocrine systems. It controls the pituitary gland, which secretes hormones

8

Pituitary gland

It has two lobes (posterior lobe and anterior lobe). Both are controlled by the hypothalamus, and is important in controlling growth, secretes hormones

9

Cerebellum

Associated with the regulation and coordination of movement and balance. Unconscious functions.

10

Medulla Oblongata

Controls automatic and homeostatic activities, such as swallowing, digestion, vomiting. Maintains vital body functions such as breathing and heart rate

11

Medulla Oblongata

- It contains a swallowing centre that coordinates the muscles of the mouth, pharynx (throat) and larynx (adam's apple) so that food will move down the oesophagus and not down windpipe.
-It also controls breathing by monitoring the level of carbon dioxide in the blood. If increase in CO2, rate and depth of breathing is increased so that more oxygen is take in
-also the cardiovascular centre of the body.

12

legions

a region in an organ or tissue which has suffered damage through injury or disease, such as a wound, ulcer, abscess, or tumour.

13

Axons

the long thread-like part of a nerve cell along which impulses are conducted from the cell body to other cells.

14

Corpus Callosum

a broad band of nerve fibres joining the two hemispheres of the brain. Allows communication between the right and left sides of the brain. Made up of myelinated neurones and called white matter.

15

Functions of Left Hemisphere

contains areas important for all forms of communication. Damage to this area could be caused by a stroke, and patients may have difficulty speaking and doing complicated movements with their hands and arms

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Functions of Right Hemisphere

It specializes in receiving and analyzing the information that comes from all of our senses. Helps us to understand what we hear and see. Patients w/ damage to this area have difficulty identifying faces and locating an object correctly in space.

17

Broca area

a brain center associated with the motor control of speech and usually located in the left side of the frontal lobe. Injury in this area interferes with ability to vocalize words

18

Wernicke area

An area located in the rear of the left temporal lobe of the brain. It is associated with the ability to recognize and understand spoken language. Injury to this area affects the ability to put words into sentences.

19

Epilepsy

a neurological disorder marked by sudden recurrent episodes of sensory disturbance, loss of consciousness, or convulsions, associated with abnormal electrical activity in the brain.

20

Optic Chiasm

a site at the base of the forebrain where the inner half of the fibers of the left and right optic nerves cross to the opposite side of the brain.

21

fMRI

Functional magnetic resonance imaging, uses radio waves and a strong magnetic field, not X-rays. Allows to see blood flow. Can see what parts of the brain are active during different activities.

22

Autopsy

inspection and dissection of a body after death, as for determination of the cause of death; postmortem examination.

23

Central Nervous System (CNS)

the complex of nerve tissues that controls the activities of the body. In vertebrates it comprises the brain and spinal cord.

24

Peripheral Nervous System (PNS)

the nervous system outside the brain and spinal cord. Somatic and autonomic systems (sympathetic and parasympathetic)

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Somatic System

Part of the PNS. Takes sensory information from sensory receptors to the Central Nervous System and then sends back motor commands from the CNS to the muscles. Pain reflex is part of this system. Voluntary control of muscles.

26

Autonomic System (ANS)

Part of the PNS. Involuntary and regulates the activities of glands, smooth muscle and the heart. Located in the medulla oblongata. In this system, there is the Sympathetic system and the Parasympathetic system, and Enteric.

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Sympathetic System

A part of the nervous system that serves to accelerate the heart rate, constrict blood vessels, and raise blood pressure. "Fight or Flight", in emergencies u need increase of glucose and oxygen. This system increases both the heart rate and stroke volume (blood pumped)

28

Parasympathetic system

The part of the involuntary nervous system that serves to slow the heart rate, increase intestinal and glandular activity, and relax the sphincter muscles. Relaxed phase=

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Neurotransmitter

a substance in the body that carries a signal from one nerve cell to another

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Sympathetic System Neurotransmitter

Noradrenaline

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Parasympathetic System Neurotransmitter

Acetylcholine

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Antagonistic

a substance which interferes with or inhibits the physiological action of another. Sympathetic system you need quick supply of glucose and oxygen in an emergency. it increases the heart rate and the stroke volume

33

Sympathetic System Functions

-increase heart rate and stroke volume
-dilates the bronchi for more oxygen
-dilates pupil of eye by making the radial muscles of the iris contract
-As digestion is not necessary in emergency, flow of blood to gut is restricted by contraction of the smooth muscle of the blood vessels carrying blood to digestive system

34

Parasympathetic System Functions

-parasympathetic nerves return the system to normal
-pupil of eye constricts (gets smaller) to protect the retina, caused by contraction of the circular muscles of the iris.
-heart rate slows and stroke volume is reduced
-blood flow returns to the digestive system
-smooth muscles of the blood vessels relax and the diameter of the blood vessels become wider

35

Bronchi

sing. Bronchus = any of the major air passages of the lungs which diverge from the windpipe.

36

Stroke volume

the amount of blood pumped by the left ventricle in each contraction

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cranial reflex

the sensory and motor neurons connect in the brain rather than the spinal cord

38

Atropine

drug used to stop the action of the neurotransmitter, acetylcholine

39

Constriction of the pupil

Happens because of a motor neurons causing the circular muscle to contact and so the radial muscle relaxes

40

optic nerve

each of the second pair of cranial nerves, transmitting impulses to the brain from the retina at the back of the eye.

41

photoreceptor

a structure in a living organism, especially a sensory cell or sense organ, that responds to light falling on it.

42

Retina

a layer at the back of the eyeball that contains cells sensitive to light, which trigger nerve impulses that pass via the optic nerve to the brain, where a visual image is formed.

43

Ganglion Cells

Retinal ganglion cells vary significantly in terms of their size, connections, and responses to visual stimulation but they all share the defining property of having a long axon that extends into the brain. These axons form the optic nerve, optic chiasm, and optic tract.

44

oculomotor nerves

each of the third pair of cranial nerves, supplying most of the muscles around and within the eyeballs.

45

Electroencephalogram (EEG)

it measures brain activity in microvolts to see if a patient is brain dead

46

Cerebral Blood Flow (CBF)

A radioactive isotope is injected into the blood stream. A radioactive counter is then placed over the head for about 30 min. If no activity, then brain dead.

47

Cerebral cortex

thin layer of grey matter covering the cerebral hemispheres. the grey matter are cells with no myelin sheath around them. less than 5mm thick and contains 75% of the body's neurones. You perform tasks such as: reasoning, language, complex thought, visual processing, motor movement, remembering and speech

48

Encephalization

the ratio between actual brain size and predicted brain mass for an animal of a given size

49

Prefrontal Cortex

Organizes thoughts, solves problems and formats strategies

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Motor association cortex

Coordinates movement

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Primary motor cortex

Plans and executes movements

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Primary somatosensory cortex

processes information related to touch

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Sensory association cortex

processes sensory information of perceptions or multi sensory information

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Visual association area

Processes visual information

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Visual Cortex

Recognizes visual stimuli, receives information from the cells in the retina of the eye.

56

Wernicke's area

Understands written and spoken language

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Auditory association area

Processes auditory information

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Auditory Cortex

Detects sound quality such as loudness and tone

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Broca's area

Produces speech and language

60

Nucleus Accumbens

associated with the reward circuit in the brain. It responds chiefly to two neurotransmitters: dopamine and serotonin. Dopamine promotes desire, while serotonin inhibits desire. The activation of dopamine in the nucleus accumbens is associated with the anticipation of a reward.

61

Ventral segmental area

Synthesizes dopamine and sends it to the nucleus accumbens through its axons.

62

pineal gland

sleep/wake patterns. This gland secretes melatonin, and it may therefore be part of the body's sleep-regulation apparatus

63

Enteric System

controls digestive system, part of the Autonomic system in the Peripheral nervous system

64

sinoatrial node

heart's natural pacemaker

65

5 components of the pain reflex:

sessory receptor, affarent receptor, afferent neuron, association neuron, efferent neuron and effector organ