Brain Bee ALL CHAPTERS

What is the largest part of the human brain?

The Cerebrum

How do the left and right hemispheres of the brain transfer information to each other?

Through bundles of nerve fibers.

What is the name of the largest bundle of nerve fibers that carry information through the left and right hemispheres?

The Corpus Callosum

What is the Cerebral Cortex and what is the purpose of its texture?

It is the outer layer of the cerebrum and its folds increase the surface area which allows it to fit more neurons which increases the brains processing power.

How are major groves in the cerebral cortex landmarks for scientists?

The most major groves separate the brain into lobes, each of which has a different function.

Which lobe in the brain is located directly in front of the eyes?

The frontal lobe

What are the characteristic functions of the frontal lobe?

• Voluntary movements and speech

• Memory and emotion

• Planning and problem solving

• personality

What lobe is located at the top of the brain? (directly behind the frontal lobe?)

The Parietal Lobe

What are the characteristic functions of the parietal lobe?

• Integrate sensory information from the skin

• Process taste

• Process some kinds of visual information

What lobe is located at the back of the brain?

The Occipital Lobes

What are the characteristic functions of the occipital lobe?

• Process visual information

• Recognize colors and shapes into complex visual understanding

What lobe is located at the sides of the brain?

The Temporal lobes

What are the characteristic functions of the temporal lobe?

• Visual Processing

• Auditory Processing

What two structures lie within the Temporal Lobe?

The Hippocampus and the AmygdalaW

What are the functions of the Hippocampus and Amygdala?

The function of the Hippocampus is to encode new memories, and the function of the amygdala is to integrate memory and emotion.

What are the parts that make up the limbic system and what are their characteristics and functions?:

• Hippocampus: Encodes new memories

• Amygdala: Integrates Memory and emotion

• Thalamus: Integrates sensory information and sends it to other parts of the brain

• Hypothalamus: Sends Hormonal signals to the rest of the body through the pituitary gland

What is the forebrain?

Limbic system + cerebral cortex

Where is the midbrain located?

Underneath the thalamus

What are the characteristic functions of the midbrain?:

• Coordinate eye movement (blinking focusing)

• Reflexes from sound

• Manage fine motor control 

What are the characteristic functions of the Basal Ganglia?

It regulates complex body movements

What are the characteristics of the Hindbrain?

• Plays roles in Glucose regulation and sleep

• Induces some regions that control movementW

Where is over half of the brain’s neurons located?

The Cerebellum

What is the second largest part of the brain?

The Cerebellum

What does the Cerebellum look like?

Deeply folded and in two hemispheres

What are the characteristic functions of the Cerebellum?

• Coordinates voluntary movement 

• Helps brain learn new motor skills

• Roles in understanding space and timing

Damage to the Cerebellum can result in what?

Uncoordinated movements like having a jerky walk, not being able to touch finger to nose

Where is the Pons located?

Bellow Cerebellum

What are the characteristic functions of the pons

• Breathing and posture

What are the characteristic functions of the medulla?

• Connects brain and spinal cord

• Swallowing, heart rate, breathing

What is the brainstem made out of?

Medulla, Pons, and Midbrain

Our involved brains closely resembles what creature?

Lancelet

Early vertebrates had three bulges, what were they and what were their functions.

Forebrain, midbrain and hindbrain, and each expanded as they got more complex.

What are groups of long chains of neurons called?

Nerve tracks

What is a group of nerve tracks called?

Neural Networks

How does the brain process visual information?

• Photoreceptors in the retina detect light.

• Signals travel through the optic nerve to the thalamus.

• The thalamus sends information to the primary visual cortex in the occipital lobe.

• The brain detects edges, color, shape, and movement.

• Information then splits into two processing streams:

• The temporal lobe identifies objects.

• The parietal lobe determines their location in space.w

What is the term for ‘A two way circuit that connects the thalamus with parts of the cortex”?

Thalamocortical Loop

How many district types of brain waves are there and what machine recognizes them?

4 types and Electroencephalograph recognizes them

What are the two types of distinct brain waves when you are awake?

• Alpha waves in parietal and occipital lobes: When awake but relaxed with eyes closed: 8-13 Hz

• Beta waves in frontal and parietal lobes: Processing sensory input or concentrates on a task: 14-30 Hz

What are the two types of distinct brain waves when you are asleep?

• Theta waves: sleep: 4-7Hz

• Delta waves: deep sleep: less than 3.5 Hz

Out of the four distinct brain waves, which two are stronger than the others?

Alpha and Delta are stronger than Beta and Theta

What are the characteristic functions of a Basil Ganglia Loop?

• Receives movement-related information from the cortex

• Produces signals that feed back to the cortex

• Excites or inhibits specific movements

What are the characteristic functions of a Brainstem and Cerebellum loop:

Timing and strength of motor signals

What are the characteristic functions of a Hippocampus and Sensory Cortex loop

Analyze familiar vs. new situations

What are the characteristic functions of a Hippocampus and Thalamus loop?

Allows memory to influence unconscious physiological responses

What are the characteristic functions of a Reflex loop?

Trigger actions before conscious thought. These never reach the cortex

Describe the structure of Neurons in the Cerebral cortex:

• They are arranged in columns and make connections with the neurons above and below 

• Each column is specialized for a task, but it is influenced by other neurons around it

What is a Neural Circuit?:

A neural circuit is a group of neurons that are connected to each other and work together to process information

What are Excitatory Neurons?

Neurons that stimulate other nearby neurons into firing signals

What are Inhibitory neurons?

Neurons that suppress the activity of neighboring neurons and regulate neural circuits

Are there more Inhibitory or Excitatory neurons in the brain?

Excitatory neurons are 80% of neurons

What is the most common type of Excitatory neuron? Describe it.

Pyramidal cell, it has a cone shaped body and two sets of dendrites that collect signals from other neurons

Which type of neuron sends signals to distant parts of the brain, and which neuron sends signals locally in their neural circuit?

Excitatory neurons pass signals through a circuit and eventually send signals to distant parts of the brain, while inhibitory neurons send signals to earlier parts of it’s circuit. 

Balance between Inhibitory and Excitatory helps with what?

• Learning

• Regulating and reducing chaotic brain signals

What happens when there is an imbalance of excitatory and inhibitory neurons?

Disorders where there are seizures like epilepsy

What are three examples of feedback loops within circuits?

Recurrent Neural Network, Feed-forward inhibitory circuit, Feedback Inhibition

What is a Recurrent Neural Network?

A network where neurons send signals forward to other neurons, but also back to its own neural circuit

What happens during a Feed-forward inhibitory circuit?

An excitatory neuron activates its own circuit, it also activates other inhibitory neurons that suppress the activity of nearby circuits.

What happens during a Feedback Inhibition?

A neuron sends signals to an excitatory neuron, it also activates other interneurons that send signals back to its own circuit and suppresses them.

What is the definition of a neuron?

A neuron is a specialized cell that can send electrical signals to other nerve cells, muscles, and glands.

What are the parts of a neuron?

• Soma: Contains the neurons nucleus, cytoplasm and molecular machinery needed to build and transport proteins for the neuron’s function

• Dendrites extend from the cell’s body and get signals from other neurons.

• The axon is another extension of the cell body and the Dendrites pass signals through the axon. Axons end in axon terminals, where the signal is passed across a synapse to other cells.

What are Glia?

Glia are cells that support neurons

What are the four types of Glia in the central nervous system?

Astrocytes, Microglia, Ependymal cells, Oligodendrocytes

What are the characteristic functions of an Astrocyte?

Regulates ion concentration around neurons, provides them with nutrients, and regulates neurons forming connections with each other

What are the characteristic functions of a Microglia?

Helps protect the brain from infections and cellular damage, and  regulates neurons forming connections with each other

What are the characteristic functions of Ependymal cells?

Make the cerebrospinal fluid that cushions the brain inside skull

What are the characteristic functions of Oligodendrocytes?

Wraps axons in a sheath called myelin which improves neuron function

How do Ions get through a neuron’s cell membrane? What happens when they move in and out?

Ions get through neuron’s cell membrane through ion channels that allows ions to enter and leave, and it keeps some out. When ions move in and out, they change the voltage difference across the membrane, and that affects if a neuron can send an electrical signal or not

What is Membrane potential?

Membrane potential is the electrical voltage difference between the inside and the outside of a neuron.

What is depolarization and Hyperpolarization?

Depolarization: Ions leaving makes membrane is less negative
Hyperpolarization: Ions coming makes membrane more negative

What is action potential?

A brief rapid electrical impulse?

What three structures make up a Synapse?

A synapse consists of the end of an axon, the dendrite of an adjacent neuron, and the space between the two called the synaptic cleft.

Which can go through a Synapse, Electrical or Chemical signals?

Chemical.

What are neurotransmitters and neurotransmission?

Chemical signals that can pass through a Synapse, and that process is called neurotransmission.

Describe the process of how neurotransmitters leave a neuron:

When an action potential (a brief electrical signal) reaches the axon terminal:

→ Voltage change opens calcium ion channels

→ Calcium ions flow into the neuron

→ Calcium binds to synaptic vesicles (packages of neurotransmitters)

→ Vesicles fuse with the membrane and release neurotransmitters into the synaptic cleft

Name substances can qualify as neurotransmitters:

Amino acids, gases. Small organic chemicals, and short peptides

Where are neurotransmitters made? Where are they transported?

Made in the Soma (cell body), and transported to the axon terminal.

After the neurotransmitters are released from the axon terminal, they go across the synaptic cleft and are binded to what?

Neurotransmitter receptors

What are the names of the two types of receptors on the postsynaptic membrane?

Ionotropic and metabotropic receptors

What are the characteristic functions of Ionotropic receptors?

Ionotropic: the neurotransmitter binds directly to part of an ion channel. The channel is normally closed, but when the neurotransmitter attaches, the receptor changes shape and opens the channel, allowing ions to flow through

What are the characteristic functions of Metabotropic receptors?

The receptors and ion channels are apart, but biochemical signals inside the cell could open an ion channel elsewhere.

What is the process of Reuptake?

When Neurotransmitters are broken down or taken back to the axon terminal

Excitatory neurons make what kind of neurotransmitters?

Neurotransmitters that open ion channels that depolarize the dendrites membrane

What is The brain's most common excitatory neurotransmitter?

Glutamate (amino acid)

What is The brain's most common inhibitory neurotransmitter?

The brain's most common inhibitory neurotransmitter is Gamma-aminobutyric acid (GABA)

Name three molecules that neurons have receptors for:

Hormones, Neuromodulators, and Prostaglandins

What is the characteristic function of a hormone?

Tells the brain about the activity of distant tissues in the body

What Is the characteristic function of Neuromodulators?

Regulate brain activity by suppressing neurotransmitter release

What are the characteristic function of Prostaglandins?

Modify brains response to pain and inflammation

What is Gene expression?

Gene expression is the process our cells use to convert the instructions in our DNA into a functional product, such as a protein

What structure is vital for turning genes on and off?

Chromatin

How does Chromatin dictate what genes are on or off?

• When chromatin is open and loosely packed, genes are accessible and can make proteins

• When chromatin is tightly packed, those genes are turned off

What Is an allele?

Different versions of the same gene

Gene-variants can cause neurological diseases. Name one.

Tay-Sachs disease.

What is the most complicated out of the 5 senses? How much perception of the Cerebral Cortex does it take up?

Vision takes up 30% of the Cerebral Cortex

What is the process of light entering your eye?

Light passes through cornea => passes through the pupil => Retina processes image => Through Optic nerve => Brain

How does your eye control how much light enters?

The iris adjusts the size of the pupil

How does your eye focus on near and far objects?

The lens gets thicker or flattens to focus on near or far objects.

How many types of neurons does the retina have? Name them

3 types. Ganglion cells, Interneurons, and Photoreceptors

What is transduction?

The process of converting one form of energy into another

Name two major kinds of Photoreceptors. Which kind is the majority?

Rods and Cones, Rods make up 94% of photoreceptors