Brain Basics Flashcards

1
Q

Formaldehyde

A

Used to preserve brains and organs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Weight of the human brain

A

3lbs, 2-3% of body weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Amount of energy the brain consumes

A

The brain consumes 20% of our body’s energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Amount of neurons the brain has, and where most are located

A

The brain has <100 billion neurons, more than 50% of these are located in the cerebellum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Neurogenesis

A

The process of formation of new neurons within the brain. Most neurogenesis happens within the womb, after we are born it happens in very small amounts only.

When we are born, we have the maximum amount of neurons we will ever have.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Neuron

A

Nerve cells that process and communicate messages and changes throughout the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Flow of a neuron signal

The path a neuron signal travels (4 parts of a neuron)

A

Dendrite → soma → axon → terminals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Dendrite

A

Parts of a neuron that receive information from other neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Soma

A

The body of a neuron. Also contains the nucleus of the neuron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Axon

A

The part of a neuron that sends neurotransmitters to other neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Synapse

A

Components that make up the connection between neurons. Includes the axon terminals and synaptic cleft.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Synaptic Cleft

A

The gap between a pre- and post-synaptic neuron. Neurotransmitters travel along this gap.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Axon Terminals

A

Release neurotransmitters into the synaptic cleft to relay signals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Nodes of Ranvier

A

Little gaps in between the myelin sheaths on an axon. They contain sodium that generates action potentials.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Projection Neurons

A

Neurons that extend from the neuronal cell body within the CNS to 1 or more distant regions of the CNS. Typically have a longer axon and fewer inputs/outputs than an interneuron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Interneurons

A

Interneurons act as a bridge of communication between the CNS and PNS, transferring signals between the two. Help with synchronization of signals as well as timing of signals (eg. for motor skills). Can also help supress sensory information by inhibiting certain signals from sensory neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Afferent Nerves/Neurons

A

Nerves/neurons that arrive at the CNS. They deliver sensory information to the brain. (A for arriving)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Efferent Nerves/Neurons

A

Nerves/neurons that deliver info from the CNS to muscles (in other words, they deliver motor signals). (E for exiting)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Glia

A

Non-neuronal cells in the central and peripheral nervous system (CNS & PNS).

Glia play a key role in brain function. However, Prof. Tomm noted we will hardly talk about them throughout the course.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Macroglia

A

Schwann cells, oligodendrocytes, astrocytes. Maintain CNS homeostasis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Microglia

A

Part of the brain’s immune response. Microglia surveil brain cells. When they sense foreign bodies, they go into a prime state.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Microglia

Prime state

A

The state when microglia sense a foreign body. They grow large and digest/”swallow” the foreign bodies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Schwann Cells

A

Schwann cells create myelin sheaths that speed up action potentials’ travels along the axon (PNS only).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Oligodendrocytes

A

Myelin creating cells (CNS only). Myelinate several different axons. Myelin speeds up the travel of action potentials.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Astrocytes

A

Glial cells that stablize the blood-brain barrier. They provide neurons with oxygen, glucose, and other nutrients. They can buffer ions in axons, adding/removing them in gap junctions. They can influence neurons at the synapse, increasing or reducing standard transmission.

Summary: Astrocytes are part of the blood brain barrier, provide neurons nutrients and influence neurons and ions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Tripartite synapse

A

Refers to the communication between three parts of the synapse (“A conversation of three”). Astrocytes shape synaptic conditions/wrap around the synapse & the pre- and postsynaptic terminals communicate. Astrocytes regulate neurotransmitter levels, modulate synaptic transmission, etc.

Astrocytes also can promote formation and stability of synapses, play a role in synaptic pruning, respond to brain injury, and help with calcium signalling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Grey matter

A

Where cell bodies of neurons are as well as where the dendrites are. Grey matter is where info is being sent and received & processes sensory information.

Grey matter makes up the outer layer of the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

White matter

A

Contains myelinated axons. The myelin is what gives white matter its colour.

White matter is found in the inner layers (subcortical tissues) of the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Nissl-stain

A

Stains cell bodies in the brain a bluish-purple.

30
Q

Fibre stain

A

Stains glial cells, so one can see where white matter in the brain is.

31
Q

Thyroxine hydroxylase

A

Enzyme involved in dopamine synthesis. Used as a marker for dopamine-related neurons in the brain when brain staining.

32
Q

Neuraxis

A

The spine-to-brain path.

33
Q

Anterior

A

Towards the front of the brain.

34
Q

Posterior

A

Towards the back of the brain.

35
Q

Superior

A

Higher/above in the brain.

36
Q

Inferior

A

Lower/below in the brain.

37
Q

Rostral

A

Towards the front of the brain in humans and animals. Points up the spinal curvature in humans.

38
Q

Caudal

A

Towards the “tail” (so for animals, towards the back of the brain, but for humans is both referring to towards the back of the brain and downwards on the axis of the brainstem/spinal cord).

39
Q

Dorsal

A

Towards the back. To humans, points to the top of our brain, but points sideways on our back. If a human had a fins like a fish, those would be visual indicators of the dorsal directions.

40
Q

Ventral

A

Towards the belly. In humans, points to the bottom of the brain and to the belly on the spinal axis.

41
Q

Medial

A

Towards the middle (of the brain).

42
Q

Lateral

A

Towards the edge (of the brain).

43
Q

Coronal Plane

A

Vertical plane that divides anterior and posterior sections of the brain.

44
Q

Sagittal Plane

A

Vertical plane that divides the brain into left and right sections. Is called a midsagittal plane if it divides the brain directly in half.

45
Q

Horizontal Plane

A

Divides the brain into superior (upper) and inferior (lower) sections.

46
Q

Peripheral Nervous System (PNS)

Somatic Nervous System

A

Sends voluntary motor signals from the CNS to muscles in the body. Collects sensory information from the body and sends it to the CNS.

47
Q

Peripheral Nervous System (PNS)

Autonomic Nervous System

A

Controls involuntary bodily functions. Heavily oriented towards internal organs/the internal bodily system

48
Q

Subsystems in Autonomic Nervous System (ANS)

Sympathetic Nervous System

A

Activate’s the body’s “fight or flight” response. Stimulates secretion of adrenaline (epinephrine) and norepinephrine.

Shuts down the digestive system so the energy can be used elsewhere.
Elevates one’s heartbeat, and stimulates glucose production/release.

49
Q

Subsystems in Autonomic Nervous System (ANS)

Parasympathetic Nervous System

A

Activates the “rest and digest” aspects of the nervous system. Conserves energy, slows one’s heart rate, and stimulates digestion.

50
Q

Related to Subsystems in Autonomic Nervous System (ANS)

Sympathomimetic drugs

A

Drugs that act on the sympathetic nervous system by mimicking its endogenous agonists. Essentially, these drugs activate the same bodily functions as our “fight or flight” response: Raised blood pressure, heart rate, and so on.

51
Q

Ganglion

A

A cluster of neurons in the PNS.

52
Q

Gyrus/gyri

A

The bumps/ridges in the brain.

53
Q

Sulcus/sulci

A

The dips/valleys in the brain.

54
Q

Longitudinal fissure

A

This fissure separates the left and right hemispheres.

55
Q

Sylvian (lateral) fissure

A

This fissure separates the temporal lobe from frontal lobe and parietal lobes.

56
Q

Forebrain

A

Where complex cognitive activities are performed. Very large in humans.

57
Q

Hypothalamus

A

An older part of forebrain, regulates sleep, body temperature, heart rate, hunger, sex drive, and thirst. Also regulates the endocrine system.

58
Q

Limbic system

A

Forms a barrier around cortical/non-cortical structures.

59
Q

Nucleus accumbens

A

Play an important role in addiction. Play a key role in our reward system overall.

60
Q

Hindbrain

A

Controls our vital survival functions (the medulla in the hindbrain controls breathing & heart rate, for example).

Lots of lethal drugs have effects on the hindbrain.

61
Q

Basal ganglia

A

Composed of caudate nucleus and putamen. Are part of controlling voluntary movement.

62
Q

Which arteries supply blood to the brain?

A

Four arteries supply blood to the brain. The left and right carotid arteries, and the vertebral arteries.

If an artery is blocked, that blood flow is gone and cannot reach the brain by any other route. This is part of why strokes are so harmful.

63
Q

Blood-brain barrier (BBB)

A

Tightly packed astrocytes wrapped around tightly packed capillaries, protects the brain from foreign entities.

64
Q

Meninges

A

Three layers of membranes that protect the brain and spinal cord.

Pia mater, arachnoid mater, dura mater

65
Q

4 total, including the skull

Layers that protect the brain and spinal cord

A

Skull -> Dura Mater -> Arachnoid mater -> Pia mater

66
Q

Cerebrospinal fluid (CSF)

A

Fluid that flows in and around the hollow/empty spaces of the brain and spinal cord. The brain produces CSF for nutrients, to remove waste, etc. but also is like an “airbag” in case we bump our heads.

67
Q

Polymorphisms

A

The presence of multiple variant forms of a specific DNA sequence among individuals/populations.

68
Q

Epigenetics

A

Enviromental factors that affect how genes work/express themselves. Can be passed down multiple generations, but epigenetic changes do not change the DNA sequence, just how it is expressed.

69
Q

Genes

Transgenic Animals

A

Animal whose genome has been altered to carry genes from a different species.

70
Q

Genes

Knockout Animals

A

Animals that have been genetically modified to lack a specific gene.

71
Q

Central Dogma of Molecular Biology

A

The theory that genetic information flows only in one direction: From DNA, to RNA, to protein (or from RNA directly to protein).