Organs pt. 1: Nervous, circulatory, respiratory

Question 1

Main regions of the nervous system

Answer 1

Central Nervous System (CNS): Brain and spine
Peripheral Nervous System (PNS): All other nerves in the body

Question 2

Brain regions

Answer 2

Hindbrain, Midbrain, Forebrain

Question 3

Hindbrain

Answer 3

Medulla: regulates blood pressure, heart rate, respiratory rate
Pons: Coordinates signals w/ other parts of the brain
Cerebellum: balance/movement coordination
Part of brain stem

Question 4

Midbrain

Answer 4

Part of Brain stem
Responsible for sleep/wake cycle, alertness and motor activity

Question 5

Forebrain

Answer 5

Includes cerebrum which is split into left and right hemispheres
Depending on location, controls: speech, reasoning/thinking, senses, emotions.
Thalamus: sensory/motor information relay
Hypothalamus: control of endocrine system

Question 6

Peripheral Nervous System (PNS)

Answer 6

Sensory/afferent division: senses/sensory neurons, signals to CNS
Motor/efferent division: Muscles/movement, signals from CNS

Question 7

Motor/efferent division

Answer 7

Autonomic NS: Involuntary movement
Somatic NS: Voluntary movement

Question 8

Autonomic Nervous system

Answer 8

Sympathetic NS: Flight or flight response
Parasympathetic NS: Rest/digest

Question 9

General Neuron Structure

Answer 9

Dendrites: Receives signal
Cell body/Soma
Axon: Signal travels
Axon terminal: Sends signal
Myelin Sheath (optional)

Question 10

Synapse

Answer 10

Junction between Axon of one neuron and dendrites of another.
Action potential triggers synaptic vesicles to release neurotransmitters
Synaptic cleft is space between axon terminal (presynaptic terminals) and the dendrite (postsynaptic terminals)

Question 11

Glial Cells

Answer 11

Helps neurons stay in place
Keep balance of chemicals between cells
Maintains Blood-brain barrier (prevents substance from getting into nervous system)
Make myelin
Produces cerebrospinal fluid
Immune functions
Astrocytes (anchor neurons to blood supply), microglial (immune defense), ependymal (cerebrospinal fluid creation), oligodendrocytes (myelin sheath)

Question 12

Action Potential

Answer 12

Use to send signal along neurons (2 milliseconds)
Resting Potential: More negative than surroundings (~-70mv, Cl-, Na+, K-)
Sodium potassium pumps: Keep at rest (Sodium out positive, Potassium in negative), let sodium in to send signals (depolarization)

Question 13

Myelin sheaths

Answer 13

Assist in sending signals
Action potential jumps from node to node (space between sheaths)

Question 14

Interneuron

Answer 14

Found in the CNS, they are multipolar and the most abundant type of neuron. They transmit signals between sensory and motor neurons.

Question 15

PNS Glial cells

Answer 15

Satellite cells (astrocytes), Schwann cells (oligodendrocytes)

Question 16

Neuron

Answer 16

Longest living cell, irreplaceable/amitotic
High metabolic rate, 25% of calories

Question 17

Neuron structure types

Answer 17

Multipolar (3 or more parts/processes) - 99%, Bipolar (2 parts/processes), Unipolar (1 part/process)

Question 18

Heart

Answer 18

Right atrium, Right ventricle (unoxygenated to lungs), Left atrium, left ventricle (oxygenated from lungs to body)

Question 19

Blood

Answer 19

Plasma (extra cellular matrix) 55% of blood
Cell types: 45%

Question 20

Systemic circulation

Answer 20

Heart to tissue, tissue to heart (after exiting left ventricle until it enters right atrium)

Question 21

Pulmonary circulation

Answer 21

Heart to lungs, lungs to heart (right ventricle until it enters left atrium)

Question 22

Veins

Answer 22

Blood to heart, largest to smallest: vena cava, veins, venules, capillaries

Question 23

Arteries

Answer 23

Blood away from heart, largest to smallest: aorta, arteries, arterioles, capillaries

Question 24

Capillaries

Answer 24

Allow for exchanges
Most organs have single system, some have portal system (2 consecutive systems), ex. brain, kidneys, small intestine)

Question 25

Circulation

Answer 25

Right atrium, right ventricle, left/right pulmonary artery, arterials-capillaries (O2/CO2 exchange), venules, pulmonary vein, left atrium, left ventricle, ascending/descending aorta, veins-venules-capillaries, organs, venules-veins, superior/inferior vena cava, right atrium

Question 26

Plasma

Answer 26

(extra cellular matrix) 55% of blood (made of 95% of water) Proteins (albumin, fibrinogen, immunoglobin), nutrients (amino acids, sugars, fatty acids), electrolytes (sodium, chloride, calcium, magnesium, bicarbonate, ions), waste products (urea, lactic acid, CO2), hormones (ADH, aldosterone)

Question 27

Cell types in blood

Answer 27

RBC (erythrocytes): biconcave shape, no organelles, 280million hemoglobin (each carry 4 O2) Leukocytes (immune cells): 1%, monocytes, granulocyte, mast cells, lymphocytes Thrombocytes (platelets): ratio to rbc 1:10, no nucleus, clotting (endothelium)

Question 28

Lungs

Answer 28

Cilia: move out material to cough out or swallow Maximize surface area (tenis court) Alveoli sacs are covered with single layer of cells (simple squamous cells) Surfactants: prevent surface tension of water (Alveolar type II cell) Diaphragm: contract (air in), relax (air out) Right lung (3 lobes, bigger), left lung (2 lobes, smaller, cardiac notch)

Question 29

CO2 transfer

Answer 29

Bicarbonate ion in plasma Small amount in RBC/as CO2 in Plasma

Question 30

Respiration

Answer 30

1. Nasal/oral cavity: Air is warmed, humidified and filtered (mucus/cilia) 2. Pharynx (junction for food/air) (epiglottis) 3. Larynx/voice box 4. Trachea (c-rings of cartilage) 5. Primary bronchus (bronchi plural) 6. Secondary bronchus 7. Tertiary bronchus 8. Terminal Bronchiole 9. Respiratory bronchiole 10. Alveolar ducts (surrounded by alveolar sacs) 11. Alveoli (alveolus singular) Intercostal muscles (between ribs), diaphragm, abdominal wall muscles

Question 31

Breathing signals

Answer 31

pH, increase of CO2=more acid/more acidic blood. Brain triggers breathing

Question 32

Alveoli cell wall

Answer 32

Epithelial cells (alveolus), basement membrane, endothelial cells (capillary)

Question 33

Alveoli function

Answer 33

Blood flows in through pulmonary arteriole to pulmonary capillary (exchange occurs), goes to heart from pulmonary venule

Question 34

Gas transfer

Answer 34

Pressure gradient causes exchange Alveolar space: PO2= 105mmHg, PCO2= 40mmHg Lumen: PO2= 40mmHg, PCO2= 45mmHg