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Neural regulation of blood pressure - baroreceptor and chemoreceptor reflexes

By: HWC, Views: 6977

• The nervous system regulates blood pressure with two reflex arcs: baroreceptor and chemoreceptor. ■ Baroreceptors (pressure) and chemoreceptors (chemical) are located in the carotid sinus and aortic arch. • Carotid sinus reflex helps maintain normal blood pressure in brain. • Ba...

Baroreceptor Reflex

By: HWC, Views: 6022

Baroreceptors located In the carotid sinus and the arch of the aorta respond to increases in blood pressure. Increased blood pressure stretches the carotid arteries and aorta causing the baroreceptors to increase their basal rate of action potential generation. Action potentials are conduct...

Rods and Cones Animation

By: Administrator, Views: 10090

A photoreceptor cell is a specialized type of neuroepithelial cell found in the retina that is capable of visual phototransduction. The great biological importance of photoreceptors is that they convert light (visible electromagnetic radiation) into signals that can stimulate biological processes...

Virtual Tour of the Eye Animation

By: Administrator, Views: 9277

Eye Composed of special anatomical structures that work together to facilitate sight: Cornea Pupil Lens Vitreous body Light stimulates sensory receptors (rods and cones) in the retina or innermost layer of the eye. Vision is made possible through the coordinated actions of nerves that co...

Neural Reflex Arc Animation

By: Administrator, Views: 9839

A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This allows for faster reflex actions to occur by activating spinal motor neurons without the delay of routing signals through the bra...

Bone tissue types - compact and spongy

By: HWC, Views: 6777

Bone tissue types • There are two types of bone tissue: compact and spongy. • All the bones of the skeleton have both kinds of bone tissue. • Compact (dense) bone • Arranged in osteons (Haversian systems), units of lamellae laid down in adjoining series of concentric rings. • P...

Metaphase I Animation

By: HWC, Views: 4670

This is a cell during metaphase I. For each pair of chromosomes, any gamete produced by this cell could contain either the maternal chromosome or the paternal chromosome. How many different combinations of maternal and paternal chromosomes are possible in the gametes produced by a cell with th...

Optic Nerve and Optic Disk Animation (Part 2 of 2)

By: Administrator, Views: 9654

The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye. The ganglion cell axons form the optic nerve after they leave the eye. The optic disc ...

Types of disease resistance: innate defenses & immunity

By: HWC, Views: 6868

Our immune system protects us and helps fight off disease. Microorganisms, small microscopic organisms, and viruses are everywhere. Ever thought about how many are on that door you just opened? Many microbes and viruses can cause disease and are termed pathogens. Plants and animals have what i...