Ch 28 & 26 Nervous and Endocrine Systems AP Bio

Specialized cells that carry both chemical and electrical signals.

• Dendrites

• Myelin Sheath

• Axon

• Nodes of Ranvier

Structures that receive signals from other nerve cells.

Extension from body that transmitters electrical action potential

Fatty covering of insulation that speeds up electrical signal. made of Schwann cells.

Area of exposed axon, acts like a junction for Schwann cells and makes electricity jump from each segment faster.

neural maintained voltage (-70mV) that is kept when no action has been triggered.

• Calculated permeability of Na (+) and K (-)

• Na/K pump (3 Na out for 2 K in)

Helps restore and maintain resting potential in neurons by pumping 3 Na out for 2 K in.

Positive charge outside, negative charge inside. Change in permeability of membrane results in an action potential.

Nerve signal which is from resting potential to peak voltage and back.

1. Membrane is stimulated.

2. Some Voltage-Gated Na channels open, short circuiting voltage in positive feedback loop.

3. Once threshold is surpassed (-50mV), voltage spikes.

4. After spike, K channels open, bringing voltage down again.

5. K channels slightly overshoot, resulting in hyperpolarization

6. Slowly voltage returns to resting potential.

-50mV

• only 1 way signals

• binary (0 or 1) signals, never analog.

• Frequency of Action Signals determines power of stimulus (PWM)

Where neurons transmit info to another nerve or effector cell. Are both electrical and chemical.

synapses with no cleft, and transmits electrical signal to its successor. Used in places of timed accuracy or of immediate responses. (Ex. Heart, Digestion)

Synapses with a cleft that transmits information via neurotransmitters. Used in places of variety of responses (ex. Skeletal movement). Converts chemical signal of Action Potential to neurotransmitters.

Space between synapse and dendrite, gap used to transmit neurotransmitters.

1. Action PE comes to synapse.

2. causes synapse to do exocytosis on neurotransmitter vesicles.

3. NT diffuses across recipient membrane.

4. NT binds to Ligand-gated Ion Channels on recipient membrane

5. channels open up for Na, starting a new action PE in recipient cells

6. NT broken down by enzymes or reabsorbed by father neuron

They allow for integration of many signals and responses, also allowing a neuron to receive signal from multiple neurons.

• Some signals excite cells, other inhibit them, giving more variety in nerve communication.

Ligands that are secreted in the body that cellular responses from target cells.

• Secreted by endocrine glands and neurosecretory cells

System that uses effector endocrine cells to regulate cellular responses in the body by working together with the nervous system.

Another name for protein.

• Pineal Gland: regulates circadian rhythms

• Hypothalamus: controls hormones used in Pituitary

• Pituitary Gland:

  • Anterior Pituitary: does the actual endocrine process

  • Posterior Pituitary: stimulate milk-producing mammary glands and contracts uterus.

• Thyroid gland: controlled metabolism and decreases calcium levels.

• Parathyroid glands: increases blood calcium.

• Testes (in males): support sperm production and puberty

• Ovaries (in females): stimulate uterine lining and puberty

• Adrenal glands:

  • Adrenal Medulla: regulates body stress and flight-fight response

  • Adrenal cortex: controls sugar, minerals absorption

• Pancreas: regulates glucose levels in blood

“Master Gland”

• Connects Nervous & Endocrine Systems.

• Instructs the Pituitary gland what to do.

• Makes the releasing and inhibitory hormones that control secretion of other hormones.

• Posterior Pituitary

• Anterior Pituitary

• Secretes: TSH, ACTH, FSH/LH, Growth Hormone, prolactin, endorphins.

• Basically the imperial bureaucracy of the Hypothalamus

Thyroid Stimulating Hormone to make T3, T4, and Calcitonin

Adrenocorticotrophic Hormone

Follicle (Gonads) Stimulating Hormone

Basically FSH but for women, stimulates the mensural cycle.

Influence growth of the Body

Stimulates the mammary glands, which produce milk.

Reward the brains and responsible for happy emotions.

• Secretes: Oxytocin & Antidiuretic Hormone (ADH) directly from Hypothalamus.

• Extension of Hypothalamus.

stimulates urine lining and mammary glands

Antidiuretic Hormone, works with Kidney to achieve hemostasis

• Secretes T4, T3, and calcitonin hormones

• Regulate metabolism, homeostasis for BP, digestion rate, Calcium in blood.

When way too much T4 & T3 is produced. Too much metabolism, leading to sweat. irritable, high BP, overheating.

When way too little T4 & T3 is produced. Too little metabolism, leading lethargy, and Graves disease: when eyes pop out a little bit.

Too little Iodine, causes big neck, and no Calcium homeostasis

Thyroxine

Triiodothyronines

Decreases Calcium in the blood by putting Ca from the bone, loosing more Ca from Kidney, and lowers blood Ca.

• Releases PTH

• works as antagonist of calcitonin to achieve Ca homeostasis in the blood.

Parathormone. Raises blood Ca by taking Ca out of the bone and increases kidney uptake of Ca.

• Secretes Insulin and Glucagon

• Regulates Glucose in the blood.

Stimulates more sugar to be released by liver cells

Stimulates more sugar to be collected into glycogen by liver cells

• Adrenal Medulla

• Adrenal Cortex

• Secretes Epinephrine Norepinephrine

• Maintains homeostasis and flight-fight response during short term stress.

trigger the flight-fight response. Beak down glucose quicker. responsible for short term stress.

• Gets stimulated by ACTH secreted by anterior pituitary.

• Secretes Glucocorticoids and mineralocorticoids.

• Boosts BP and energy for long term stress.

Breaks down protein and fat into glucose to provide more energy. May suppress immune system.

keeps more sodium and waters in Kidney, increasing blood volume and pressure.

• Get triggered by pituitary LH and FSH hormones.

• Secrete Androgens (Testosterone), Progesterone, Estrogen

help develop male characters.

Increases pregnancy traits

Increases womanly traits