B MCAT--Endocrine, Nervous Systems

Question 1

cerebellum

Answer 1

Part of brain affiliated with intricate muscle movements, posture and balance.

Question 2

cerebrum

Answer 2

The cerebrum comprises gray matter (the cerebral cortex) and white matter at its center.

Functions as the motor cortex and regulates temperature.

Question 3

occipital lobe

Answer 3

Part of cerebral cortex responsible for visual processing.

Question 4

brainstem

Answer 4

Brain stem is responsible for basic vital life functions; breathing and cardio.

Includes medulla oblongata, which connects the brain to the spinal cord and is responsible for regulating breathing, heartbeat, and blood pressure.

Question 5

basal ganglia

Answer 5

smooth motor movements and posture.

(Parkinson’s disease is a result of damage to the basal ganglia)

Question 6

frontal lobe

Answer 6

Part of cerebral cortex affiliated with personality changes.

Question 7

hippocampus

Answer 7

Part of limbic system of brain responsible for formation and consolidation of memories.

Question 8

prefrontal cortex

Answer 8

Prefrontal cortex is responsible for processing and displaying negative emotion; rational decision-making, reducing impulsive behaviors.

Covers the front of the frontal lobe in the brain’s cerebral cortex.

Question 9

cerebellum

Answer 9

coordinates and regulates muscle activity–balance and posture

Question 10

pons

Answer 10

Part of brain close to the stem.

Relays info and regulates arousal, sleep, autonomic functions.

Question 11

medulla oblongata

Answer 11

Regulates critical autonomic functions of breathing, heartbeat, and blood pressure.

Located at top of brainstorm. Connects the brainstorm to the brain.

Question 12

Anterior cingulate cortex

Answer 12

region of brain involved in higher order cognition–impulse control and decision-making.

Located beneath cerebral cortex.

Question 13

Path of sensory receptors

Answer 13

stimulus > receptor (sensory cell or nerve ending) > sensory ganglion > central nervous system

Question 14

photoreceptors

Answer 14

Sensory receptors that detect light

Question 15

hair cells

Answer 15

Sensory receptors that help with hearing–linear/rotational movement and acceleration.

Question 16

Nociceptors

Answer 16

Sensory receptors that detect pain

Question 17

Thermoreceptors

Answer 17

Sensory receptors that detect temperature

Question 18

Osmoreceptors

Answer 18

Sensory receptors that detect osmolarity/salinity; the concentration of solutes of something.

Important in blood to sense correct volume of water and solutes–hydration.

Question 19

Olfactory receptors

Answer 19

Sensory receptors that detect smell.

Question 20

Taste receptors

Answer 20

Sensory receptors that detect taste.

Question 21

Term for the Somatosensation of pain

Answer 21

nociception

Question 22

Sense of knowing where you and your limbs are in space

Answer 22

Proprioception.
Also called kinesthetic sense

Question 23

Sense of keeping balance and detecting acceleration

Answer 23

Vestibular sense

Question 24

Sense of touch–vibration, pressure, temperature, and nociception

Answer 24

somatosensation

Question 25

Ganglion Cells

Answer 25

In the visual pathway, ganglion cells collect information from all the retinal cells (including the rods and cones), grouping it to form the optic nerve.

Question 26

Neurotransmitter--Acetylcholine

Answer 26

Involved in CNS & PNS. Voluntary muscle control; involved in Parasympathetic nervous system.

Question 27

Neurotransmitters--Epinephrine, Neuroepinephrine

Answer 27

Involved in PNS. (Adrenalin) Fight or flight responses, wakefulness, alertness

Question 28

Neurotransmitters--Dopamine

Answer 28

Involved in CNS. Coordinates smooth movements, postural stability. Involved in pleasure center (septal nuclei).

Question 29

Neurotransmitter--Serotonin

Answer 29

Involved in CNS. Mood, sleep, eating, dreaming.

Question 30

Neurotransmitter--GABA

Answer 30

Involved in CNS. INHIBITORY. Involved in stabilization. Increase in GABA = decrease in brain activity. Calming effect.

Question 31

Neurotransmitter--Endorphins

Answer 31

Involved in CNS. Brains natural painkillers. Act directly on spinal cord. Pain info brought in, endorphins shut down info in spinal cord before pain signals make it to brain. Opioids and morphine are famous for functioning in a similar way to endorphins

Question 32

Endocrine Signaling

Answer 32

endo-crine = into the blood. A form of cell-to-cell communication. Hormones secreted into the bloodstream. Travel to distant locations to cause changes in cellular expression. Signaling can act DIRECTLY on target tissue (e.g. growth hormones on bone) or TROPICLY where it requires an intermediary (gland) to release a second (or third) direct hormone.

Question 33

Glands of the endocrine system

Answer 33

HYPOTHALAMUS: In the brain. Controls endocrine system. Mood, hunger and thirst, sleep patterns and sexual function. PITUITARY: Pea-sized gland in the base of brain. Makes hormones that control several other glands. How your body grows. THYROID: butterfly-shaped gland in the front of your neck. Metabolism. PARATHYROID: 4 tiny glands. Control calcium (necessary for heart, kidneys, bones and nervous system). ADRENAL: 2 adrenal glands, 1 on top of each kidney. They control metabolism, blood pressure, sexual development and response to stress. PINEAL: Manages sleep via melatonin. PANCREAS: Insulin. OVARIES: 2 in lower abdomen of women. Release estrogen, progesterone and testosterone. TESTES: In men, the 2 testes (testicles) make sperm and release the hormone testosterone, also affecting muscle strength and sex drive.

Question 34

Paracrine Signaling

Answer 34

Cell-to-cell communication between nearby cells through extracellular fluid. presynaptic membrane > synapse > postsynaptic membrane para = Greek for side-by-side.

Question 35

Juxtacrine Signaling

Answer 35

Cell-to-cell communication between cells that are in close contact with each other or directly adjacent. (no intermediate fluid necessary)

Question 36

Autocrine Signaling

Answer 36

Cell-to-cell communication where signals are released and accepted by the same cell. auto = Greek for self.

Question 37

Peptide hormones

Answer 37

Peptide hormones are made of amino acids chains. All hormones are chemical messengers that travel through the blood. Can not pass through the plasma membrane of cells. Relatively polar. Bind to very specific extracellular receptors. Affect translation, not transcription. Fast onset. Short acting. Ex. Oxytocin, insulin, epinephrine. Tend have"-in" ending. Also glucagon, ATCH.

Question 38

Steroid Hormones

Answer 38

Made of cholesterol. All hormones are chemical messengers that travel through the blood. Slower onset. Longer lasting change. CAN pass through the plasma membrane of cells and into the nucleus. Relatively hydrophobic. Can bind to DNA, changing transcription. Can NOT travel through the bloodstream easily; need carrier proteins (e.g. sex hormone binding globulin, albumin). Ex. Testosterone. Tend to have "-ol", "-one", "-oid" endings.

Question 39

Hormones of the anterior pituitary gland

Answer 39

Portal system. They take the path: hypothalamus > (via GnRH) > anterior pituitary gland > (via FSH to) > organ. Organ can be gonads, thyroid, or adrenals. FLAT PEG FLAT are all tropic hormones. PEG are all direct hormones. FSH - Maturation of germ cells LH - secretion of androgens ACTH - secretion of corticosteroids TSH - influences metabolism Prolactin - production and secretion of milk Endorphins - inhibit pain GH - Bone and muscle cell growth

Question 40

Hormones of the posterior pituitary gland

Answer 40

Unique in that rather than a portal system, the posterior pituitary glad is an axon; its cell body is in the hypothalamus, that is where the hormone is made; then stored and released by the posterior pituitary gland. Think of as posterior pituitary "purse". ADH- increases water reabsorption in kidney Oxytocin- promotes uterine contraction, milk letdown

Question 41

Hormones of the thyroid

Answer 41

Generally responsible for metabolism. T3/T4 - regulates basal metabolic rate Calcitonin - decreases calcium in blood (antagonist to PTH hormone)

Question 42

Hormone of the parathyroid gland

Answer 42

Parathyroid hormone (PTH) - Increases calcium in blood

Question 43

Hormones of the adrenal glands (above the kidney)

Answer 43

Glucocorticoids - Increase blood glucose Mineral corticoids - increase sodium reabsorption Cortical sex hormones - stimulate sexual differentiation Adrenaline epinephrine / norepinephrine- active in the fight or flight response (from the adrenal medulla)

Question 44

Hormones of the pancreas

Answer 44

Pancreas is site of many digestive hormones. Insulin - uptake and storage of glucose (released when you eat a lot of food) Glucagon- breakdown of glycogen (released when food is sparce) Somatostatin- inhibits release of insulin and glucagon; brings back to status quo

Question 45

Root words CORTEX vs. MEDULLA

Answer 45

Cortex refers to the outer layer of an organ or gland. Medulla refers to the inner layer of an organ or gland.

Question 46

Hormones of the gonads

Answer 46

Gonad glands are responsible for: Estrogen-Female differentiation Testosterone- male differentiation

Question 47

Hormone of the pineal gland

Answer 47

Melatonin - regulates circadian rhythms

Question 48

cortisol

Answer 48

cortisol = stress hormone; secreted from adrenal cortex.

Question 49

aldosterone

Answer 49

aldosterone = hormone related to blood pressures; secreted from the adrenal cortex.

Question 50

glial cells

Answer 50

Glial cells are a type of cell that provides physical and chemical support to neurons and maintain their environment.

Question 51

What are the two types of glial cells that form myelin?

Answer 51

There are two types of glial cells that form myelin. Oligodendrocytes in the central nervous system, and Schwann cells in the peripheral nervous system. Note, MS targets the demyelination of oligodendrocyte nerve cells in the central nervous system.

Question 52

electrotonic spread and saltatory conduction in a neuron

Answer 52

Electrotonic spread is the spread/dissipating of charge across the axon of a neuron. Saltatory conduction is the boosts of charge along an axon due to periodic gated channels, triggered in response to electrotonic spread. A charge threshold on the voltage gradient is met so that opens the channels and allows NA^2+ to flood in, boosting the signal.

Question 53

neuroplasticity-- potentiation and depression

Answer 53

neuro potentiation represents neuro plasticity/changes based on increased use. Synaptic changes might include more neurotransmitter released, less reuptake, more receptors. Structural changes may include sprouting of more dendrites and axons. INCREASED RESPONSE. neuro depression happens when a neuron is not active. Opposite effect.