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Chemical Synapse Animation

By: HWC, Views: 5095

A neuromuscular junction is a chemical synapse between the axon endings of a motor neuron and a muscle cell. A narrow synaptic cleft separates the presynaptic cell (the motor neuron) from the postsynaptic cell (the muscle cell). The presynaptic cell contains vesicles filled with neurotransmitt...

System organization - PPM system types (Somatic, Autonomic & Enteric) and Reflex arc types

By: HWC, Views: 7860

• The PNS consists of all nervous tissue outside of the CNS. • It is divided into three functional components: • Somatic nervous system (SNS) • Autonomic nervous system (ANS) • Enteric nervous system (ENS) • The SNS consists of: • Sensory neurons from skeletal muscles ...

Structures that affect circulation - venous return

By: HWC, Views: 7561

• Venous return directly affects cardiac output. • Increased venous return leads directly to greater cardiac output whereas decreased return contributes to decreased output. • Venous return depends on: • Blood volume regulation by the kidneys. • Venous tone. • Skeletal muscl...

ATPase function - membrane transport, contractile proteins and synthesis

By: HWC, Views: 8091

• Energy from ATP is used to move ions across the cell membrane during active transport. • This membrane protein transports sodium out of the cell and potassium into the cell. As such, it is called a sodium-potassium pump. • Because this pump also acts as an enzyme to hydrolyze ATP it i...

Structures that affect circulation - heart and systolic/diastolic BP

By: HWC, Views: 7635

• Heart generates blood pressure. • Arterioles produce resistance thereby regulating blood flow to tissues. • Veins store blood; kidneys regulate blood volume; both affect venous return and cardiac output. ■ Contractions of the ventricles determine blood pressure, which drives th...

Exercise and cardiac output & Definition of stroke volume

By: HWC, Views: 7675

▪ Cardiac output: • Maintains blood flow throughout the body. • Measure of blood volume ejected from the heart over a given time. • Determined by multiplying heart rate by stroke volume (CO = SV x HR). • Heart rate: Number of beats/min. • Stroke volume: Amount of blood eject...

Regulation of GFR: three methods, autoregulation & autoregulation via myogenic mechanism

By: HWC, Views: 8157

• GFR can be regulated by adjusting: • Blood flow in and out of the glomerular capillaries. • Surface area of glomerular capillaries. • There are three main ways to make these adjustments: • Renal autoregulation. • Nervous regulation. • Hormonal regulation. • Ren...

Cortisol (protein catabolism, gluconeogenesis, vasoconstriction & anti-inflammation)

By: HWC, Views: 7305

• Stressors stimulate production of hypothalamic releasing hormones, corticotropin releasing hormone, hormone (CRH) and adrenocorticotropic hormone (ACTH) stimulate. • These hormones promote increased production of 1 cortisol from the zona fasciculata cells of the adrenal cortex. • Cort...

Cardiac conductile cells

By: HWC, Views: 7974

• In order for the heart to function properly, all of its cells must contract in a specific sequence. This sequence is determined by a pathway known as the conduction system. • Cardiac muscle cells have two attributes that enable the conduction system to work: • Connective. Action pot...