GLOBAL CONTEXT: Scientific and Technical Innovation: We use this Scientific and Technical Innovation global context because we are using the technology for researching information that we need and can be useful for our project. Also we can research on books or ask to our family to know more about the topic that we need; in this case the SPINAL CORD
KEY CONCEPT: Systems: We use the key concept system because we are learning how the spinal cord works with others parts of the body, and how it works perfect to make us walk or to stand in the ground; because without the spinal cord we can´t do nothing.
RELATED CONCEPT (S) Patterns-Interactions We use the related concept patterns and interaction because we are studying how the system interact each other to do us move anyway without any complication so we think that this is pretty perfect and pretty awesome how all is do perfectly
What is the Spinal cord? The spinal cord is a soft bundle of nerves that extends from the base of the brain to the lower back. It runs through the spinal canal and is protected by the bones of the spine (vertebrae). Messages between the brain and the nerve roots travel up and down the spinal cord, making it possible for the brain and body to communicate. The discs cushion the vertebrae and provide flexibility to the spine and spinal cord.
(meninges). The spinal cord and meninges are contained in the spinal canal, which runs through the center of the spine. In most adults, the spine is composed of 26 individual back bones (vertebrae). Just as the skull protects the brain, vertebrae protect the spinal cord. The vertebrae are separated by disks made of cartilage, which act as cushions, reducing the forces generated by movements such as walking and jumping.
How the Spine Is Organized?
The spinal cord is a long, fragile tube-like structure that begins at the end of the brain stem and continues down almost to the bottom of the spine (spinal column). The spinal cord consists of nerves that carry incoming and outgoing messages between the brain and the rest of the body. It is also the center for reflexes, such as the knee jerk reflex. Like the brain, the spinal cord is covered by three layers of tissue
A column of bones called vertebrae make up the spine (spinal column). The vertebrae protect the spinal cord, a long, fragile structure contained in the spinal canal, which runs through the center of the spine. Between the vertebrae are disks composed of cartilage, which help cushion the spine and give it some flexibility. Like the brain, the spinal cord is covered by three layers of tissue (meninges).
The sensory roots carry information to the brain from other parts of the body.
Spinal nerves: Emerging from the spinal cord between the vertebrae are 31 pairs of spinal nerves. Each nerve emerges in two short branches (roots):
Cauda equina: The spinal cord ends about three fourths of the way down the spine, but a bundle of nerves extends beyond the cord. This bundle is called the cauda equina because it resembles a horse’s tail. The cauda equina carries nerve impulses to and from the legs.
One at the front (motor or anterior root) of the spinal cord One at the back (sensory or posterior root) of the spinal cord
The motor roots carry commands from the brain and spinal cord to other parts of the body, particularly to skeletal muscles.
Like the brain, the spinal cord consists of gray and white matter. The butterfly-shaped center of the cord consists of gray matter. The front “wings� (called horns) contain motor nerve cells, which transmit information from the brain or spinal cord to muscles, stimulating movement. The back horns contain sensory nerve cells, which transmit sensory information from other parts of the body through the spinal cord to the brain. The surrounding white matter contains columns of nerve
fibers that carry sensory information to the brain from the rest of the body (ascending tracts) and columns that
carry impulses from the brain to the muscles (descending tracts).
What is the vertebral column? The vertebral column is a vertical series of approximately 33 small bones (known as vertebrae), which are separated by intervertebral discs. It can be separated into five different regions, with each region characterized by a different vertebral structure. In this article, we shall look at the anatomy of the vertebral column – its structure, joints and ligaments.
Functions The vertebral column has four main functions: • • • •
Protection – encloses and protects the spinal cord within the spinal canal. Support – carries the weight of the body above the pelvis. Axis – forms the central axis of the body. Movement – has roles in both posture and movement.
Vertebral Structure Vertebral Body The vertebral body is the anterior part of the vertebrae. It is the weightbearing component, and its size increases as the vertebral column descends (having to support increasing amounts of
weight). The superior and inferior aspects of the vertebral body are lined with hyaline cartilage. Adjacent vertebral bodies are separated by a fibrocartilaginous intervertebral disc.
Vertebral Arch
Classifications of Vertebrae
The vertebral arch refers to the lateral and posterior parts of the vertebrae. With the vertebral body, the vertebral arch forms an enclosed hole, called a vertebral foramen. The foramina of the all vertebrae line up to form the vertebral canal, which encloses the spinal cord.
Cervical Vertebrae
There are seven cervical vertebrae in the human body. They have three main distinguishing features: The spinous process bifurcates into two parts, and so is known as a bifid spinous process. There are two transverse foramina, one in each transverse process. These conduct the vertebral arteries. The vertebral foramen is triangular in shape
Thoracic Vertebrae The twelve thoracic vertebrae are medium-sized and increase in size as they move down the back. Their main function is to articulate with ribs, producing the bony thorax. The vertebral foramen is circular.
Lumbar Vertebrae These are the largest of the vertebrae, of which there are five. They act to support the weight of the upper body and have various specializations to enable them do this. Lumbar vertebrae have very large vertebral bodies, which are kidney-shaped. However, like the cervical vertebral, they have
a triangular shaped foramen.
vertebral
Sacrum and Coccyx The sacrum is a collection of five fused vertebrae. It is described as an upside-down triangle, with the apex pointing inferiorly. On the lateral walls of the sacrum are facets, for articulation with the pelvis at the sacro-iliac joints. The coccyx is a small bone, which articulates with the apex of the sacrum. It is recognized by its lack of vertebral arches. Due to the lack of vertebral arches, there is no vertebral canal, and so the coccyx does not transmit the spinal cord.
Joints Each vertebra has five articulations. The vertebral bodies indirectly articulate with each other, and the articular processes also form joints.
How do signals move through the nervous system?
What is a neuron?
Your nervous system works by receiving information from the environment and translating that information into electrical signals. Those electrical signals are sent from the brain to the rest of the body by special cells called neurons. Neurons (also called neurones or nerve cells) are the fundamental units of the brain and nervous system, the cells responsible for receiving sensory input from the external world, for sending motor commands to our muscles, and for transforming and relaying the electrical signals at every step in between. More than that, their interactions define who we are as people. Having said that, our roughly 100 billion neurons do
interact closely with other cell types, broadly classified as glia (these may actually outnumber neurons, although it’s not really known).
What does a neuron look like?
A useful analogy is to think of a neuron as a tree. A neuron has three main parts: dendrites, an axon, and a cell body or soma (see image below), which can be represented as
What are nerve impulses?
A nerve impulse is the way nerve cells (neurons) communicate with one another. Nerve impulses are mostly electrical signals along the dendrites to produce a nerve impulse or action potential. The action potential is the result of ions moving in and out of the cell.
the branches, roots and trunk of a tree, respectively. A dendrite (tree branch) is where a neuron receives input from other cells. Dendrites branch as they move towards their tips, just like tree branches do, and they even have leaf-like structures on them called spines. The axon (tree roots) is the output structure of the neuron; when a neuron wants to talk to another neuron, it sends an electrical message called an action potential throughout the entire axon. The soma (tree trunk) is where the nucleus lies, where the neuron’s DNA is housed, and where proteins are made to be transported throughout the axon and dendrites. Specifically, it involves potassium (K+) and sodium (Na+) ions. The ions are moved in and out of the cell by potassium channels, sodium channels and the sodium-potassium pump.A nerve impulse is an electrical signal that travels along an axon. There is an electrical difference between the inside of the axon and its surroundings, like a tiny battery. When the nerve is activated, there is a sudden change in the voltage across the wall of the axon, caused by the movement of ions in and out of the neuron. This triggers a wave of electrical activity that
passes from the cell body along the length of the axon to the synapse.
What are Sensory Neurons?
what's occurring in the environment. A neuron is a specialized type of cell that transmits signals. A series of neurons can send a signal from your little toe all the way to your brain, where the signal is processed. Sensory neurons make up your five primary senses (smell, taste, sight, touch, and hearing) allowing you to smell a banana or feel scalding coffee that's splashed on your arm. Let's take a closer look at each of these senses.
If someone removed the top of your skull and poked your brain with their finger, would you feel it? Nope! Yet, if that same person pricked the tip of your finger with a pin, it would hurt. Why is this? Your brain is entirely isolated, floating in fluid in your skull, and it relies on connections to special neurons, called sensory neurons, throughout the body to understand
Smell and Taste
When the aroma of a banana, in the form of odor molecules, floats into your nose, the molecules dissolve in your mucus and spread throughout it. The molecules then attach to projections called microvilli, which are like little fingers. In the microvilli are the branching tips of neurons, called dendrites. A single sniff of a banana can cause millions of odor molecules to flood your
nose, which comes into contact with hundreds, if not thousands, of dendrites. This contact causes the neuron to send a signal to a part of the brain that deals with the sense of smell.
a change in pH. Think acids and bases (which can affect sourness), changes in sodium ions (which can affect saltiness), and complex triggers to various other chemicals (which can affect bitterness).
Taste buds, the little bumps on your tongue, are also sensory neurons. They work with olfactory receptors in your nose to detect different flavors in food.
Neurons carry information from the body to the brain, and carry instructions from the brains back to the rest of the body. The two groups of neurons are sensory neurons and motor neurons.
These highly sensitive neurons can detect chemical differences, such as
Motor neuron
A motor neuron (or motoneuron) is a neuron whose cell body is located in the motor cortex, brainstem or the spinal cord, and whose axon (fiber) projects to the spinal cord or outside of the spinal cord to directly or indirectly control effector organs, mainly muscles and glands. There are two types of motor neuron – upper motor neurons and lower
motor neurons. Axons from upper motor neurons synapse onto interneurons in the spinal cord and occasionally directly onto lower motor neurons. The axons from the lower motor neurons are efferent nerve fibers that carry signals from the spinal cord to the effectors. Types of lower motor neurons are alpha motor neurons, beta motor neurons, and gamma motor neurons. The term 'motor neuron' is usually restricted to the lower motor neurons, the efferent nerves that directly innervate muscles.
REFLECTION We are using the Scientific and Technical Innovation to help us researching what we need to our interdisciplinary project, also for us this project has been very interesting to do because we like to learn about the body, so we think that our thoughts and our investigations will help us to do the presentation very well while we study. On the other hand, the project was a little tedious because we didn’t know how to join our parts in one work but with the Technical Innovation we research on YouTube how to join the parts of every one, on one page of word office and we did it very well. Finally, with the approval of the teacher we can do the presentation well and self-security of us. BIBLIOGRAPHY Recuperated from: https://www.msdmanuals.com/home/brain,-spinal-cord,-and-nerve-disorders/biology-ofthe-nervous-system/spinal-cord http://teachmeanatomy.info/back/bones/vertebral-column/ https://qbi.uq.edu.au/brain/brain-anatomy/what-neuron https://www.sciencedaily.com/terms/sensory_neuron.htm https://www.sciencedaily.com/terms/sensory_system.htm https://www.britannica.com/science/motor-neuron http://whoami.sciencemuseum.org.uk/whoami/findoutmore/yourbrain/howdoesyourbrainw ork/howdoesyournervoussystemwork/whatarenerveimpulses
Made by: David Mendoza Carolina Almache Alejandro Cadena