Unit 3 Build a Moveable Limb

A & B: A represents the muscle relaxed and B represents the muscle flexed.

The parts of the elbows

1 Biceps Muscle

2 Biceps Tendon

3 Ulnar Nerve

4 Humerus

5 Radius

6 Ulna

7 Posterior Band

8 Anterior Band

9 Intermediate Band

10 Annular Ligament of Radius

Unit 3 Lab Project: Build A Moveable Limb

Introduction: This is a model of a moveable elbow built out of construction paper and metal brads that connected the bicep to the anterior band. The parts that are found in the model are bones, tendons, and muscles. Each one of these allow it to bend and contract.

Conclusion: By building a model I have learned about how bones, tendons and muscles allow our bodies to move a certain way. In certain different parts of the body bones, muscles and tendons can aid in supporting and protecting our bodies. The elbow works simular to a hinge because it bends and straightens. All the nerves that travel down the arm pass through the elbow and these nerves carry signals from the brain to the muscles and this makes the arm move. The elbow is what provides stability as we position our forarm to use our hand.

Online lab: leeches

What is the electrode measuring? It is a concept that deals with voltages.

Why use leeches in neurophysiology experiments? They are relatively small in number and have a large size of neurons.

What is the difference between a sensory and a motor neuron? A sensory neuron is a nerve cell that transmits nerve impulses to the cns after a sensory receptor has been stimulated. A motor neuron conducts impulses away from the cns and innervates effectors.

Do you think a leech experiences pain? What is pain? No they do not feel pain because they do not have the necessary brain systems that vertebrates have in order to process pain.

What were the two most interesting things about doing this lab? Just learning about neurophysiology in all because i had never learned anything about them before.

Anything you found confusing or didnt like about the lab? Just trying to figure out the lab at first was a little confusing.

Online Lab: Muscle Function

Muscle Functions:

1. Place your fingers along the angle of your jaw just in front of your ear. Grit your teeth and observe what happens to the hardness of the muscles in your check. They move up towards your ear and protrude out.

2. With the thumb and little finger of one hand, span the opposite arm's biceps from the elbow to as close to the shoulder as possible. Bend the arm and observe the change in the length of the muscle. The muscle goes from lose to tight.

3. Wrap a strip of paper around your upper arm and mark the circumference of your arm on the paper. Clench your fist tightly and mark the new circumference on the paper. Observe what happens to the circumference of the muscle. The muscle gets bigger.

Effects of Temperature on muscle action:
Normal: 48
Ice Water: 29

Effect of fatigue on muscle action
# of squeezes in 20 seconds
1 40
2 41
3 42
4 32
5 31
6 31
7 22
8 22
9 19
10 12

What are the three changes you observed in a muscle while it is working? The three changes that I notice by doing the lab is that it once your mucsle gets tired it unable to go as fast as it did.

What effects did the cold temperature have on the action of your hand muscle? When your hand muscle get colder it makes it harder for it to go as fast as it did when it was at your normal temperature.

Ethical Issue 3 Exercise

I feel that exercise is the most important thing that you can do. By exercising it helps you stay young and maintain a healthier body. I played sports all through high school and my first two years of college. So by taking part in different types of sports and being in a weight training class, I learned a great deal about exercise and how it benefits me. While taking part in exercise I find that it has increased my self confidence. When I’m feeling stressed working out is the best way to release it. I believe the high increase of child obesity in the United States is due to the lack of education of how exercise will help you maintain a healthier body weight. If every child would take part in some form of exercise everyday, they would loose weight and therefore wouldn’t be at such a health risk. . We can better America by making a gym class mandatory throughout grade school and high school. For most kids the only time that they actually get any type of exercise is at school through a weight or gym class. When gym class was removed from most schools as a required class, this is when the child obesity rate started to increase at an alarming rate. Parents and guardians also need to enforce that their children shut off the television and video games and do some kind of exercise instead.

Compendium Review Chapters 13, 14

Chapter 13
Nervous system has two major divisions
Central nervous system contains the brain and spinal cord
Peripheral nervous system contains nerves. The nerves lie outside of the central nervous system.
The nervous system has three specific functions
nervous system receives sensory input
the CNS performs integration
the CNS generates motor output.

Nervous tissue contains two types of cell neurons which are cells that transmit nerve impulses between parts of the nervous system. The second type is Neuroglia that support and nourish neurons.
Neuron structure there is 3 different types
Sensory neuron takes messages from sensory preceptor to the central nervous system.
Interneuron lie entirely with the CNS they can input from sensory neurons along with other interneuron in the CNS.
Motor neuron takes impulses away from the CNS to muscle fibers or glands.
Nerve impulses have information within the nervous system. It is studied by using excised axons and voltmeter to measure voltage.
A terminal that lies very close to a dendrite or the cell body of another neuron. The region of close space is called a synapse. At this space there is a small gap called a synaptic clerk that separates the sending from the receiving neurons.
The central nervous system
The brain and the spinal cord make up the central nervous system. It is where sensory information is received and motor control is initiated. Both the spinal cord and the brain are protected by bone, the brain is enclosed by the skull and the spinal cord is surrounded by vertebrae. Along with bone they are also protected by membranes known as meninges. Then the spaces between the meninges is filled with fluid called cerebrospinal fluid which cushions and protects the central nervous system.
The spinal cord extends from the base of the brain through a large opening in the skull and into the vertebral canal formed by openings in the vertebrae.
The functions of the spinal cord
It is a mean of communication between the brain and the peripheral nerves that leave the cord. When someone touches you sensory receptors generate nerve impulses that pass through sensory fibers to the spinal cord and up ascending tracts to the brain.
The brain
The goal of modern neuroscience is to better understand the structures and functions of the working brain. This will help in preventing or correcting the thousands of mental disorders that affect many people. There are many parts in the brain that have different functions that help it.
The peripheral nervous system your eyes send messages by way of a cranial nerve to the brain, allowing you to read a page and your brain is directing the muscles in your fingers to turn the page by way of the spinal cord and a spinal nerve.
Humans have 12 points of cranial nerves attached to the brain cranial nerves are largely concerned with the head, neck, and facial regions of the body.
The nerves in the somatic system serve the skin, skeletal muscles and tendons and it contains nerves that take sensory information from external sensory receptors to the CNS and motor commands away from the CNS to the skeletal muscles.
Autonomic system regulates the activity of cardiac and smooth muscles and glands. The system is divided into the sympathetic and parasympathetic divisions. Activation of these two systems causes opposite response.
Drug abuse has an affect on the nervous system and can affect your mood and or emotional state. These drugs have two affects such as on the limbic systems, and they promote or decrease the action of a particular neurotransmitter.
Stimulants are drugs that increase the likelihood of neuron excitation and depressants decrease the likelihood of excitation. Some of the names of these drugs that affect the body in different ways are alcohol, nicotine, cocaine, methamphetamine, heroin and marijuana.

Chapter 14
Sensory receptors are dendrites that detect a certain type of stimuli
Exteroceptors are sensory receptors that detect stimuli from outside the body, such as those that result in taste, smell, vision, hearing and equilibrium
Interceptors receive stimuli from inside the body
Different types of sensory receptors
Chemoreceptor’s respond to chemical substances
Pain receptors are types of chemoreceptor’s they are naked dendrites that respond to chemical released by drainage tissues
Pain receptors alert us to possible danger.
Photoreceptors respond to light energy. Our eyes have photo rectors that are sensitive to light rays and provide us with a sense of vision. Stimulation to photoreceptors also known as rod cells affect black and white vision and stimulation of the photoreceptors known as cone cells results in color vision.
Mechanoreceptors are stimulated by mechanical forces which have to do with some kind of pressure. When we hear airborne sound waves are changed into fluid borne pressure waves that are detected by mechanoreceptors in the inner ear.
Sensory receptors respond to environmental stimuli by having nerve impulses. When they reach the cerebral cortex of the brain, sensation which is conscious perception of stimuli occurs. All sensory receptors require nerve impulses and the sensation that results depends on the part of the brain receiving the nerve impulses.
Proprioceptors and cutaneous receptors
Proprioceptors are mechanoreceptors that affect reflex action that maintain muscle tone and thereby the body’s equilibrium and posture. This helps us know the position of our limbs in space by detecting the degree of muscle relaxation, the stretch of tendons and fine movement of ligaments.
Cutaneous receptors
The two layers of the skin are the Epidermis and the Dermis. Epidermis is stratified squanmous epithelium in which cells become keratinized as they raise to the surface. Dermis is a thick connective tissue layer. The dermis contains cutaneous receptors that make the skin sensitive to touch, pressure, pain, and temperature. These types of cutaneous are sensitive to fine touch. Two types are sensitive to pressure.
Sense of taste and smell
Sense of taste in adults happens by the 3,000 taste buds that are located mostly on the tongue. There are four types of taste: sweet, sour, salty, and bitter. Then a fifth taste bud might exist which is called umami. This is for certain flavors of cheese, beef broth, and some seafood. Taste buds are located in certain places for certain tastes. The tip of the tongue is most sensitive to sweet tastes making it especially pleasurable to lick ice cream cones. The margins of the tongue are most sensitive to salty and sour taste and the rear of the tongue to bitter tastes. The brain receives taste by messages.
Sense of smell
80% - 90% of what we taste actually is due to the sense of smell. Our sense of smell depends on between 10 and 20 million olfactory cells located high in the roof of the nasal cavity. How the brain receives odor information. Every odor contains odor molecules this activates a characteristic combination of receptor proteins. An odor signature is figured by which neurons are stimulated. Once the neurons have communicated this information to the olfactory tract then it is sent to the olfactory areas of the cerebral cortex. That’s how we know that we have smelled.
Sense of vision
A lot of processing of stimuli occurs in the eyes before nerve impulses are transferred to the brain. Researchers believe that about a third of the cerebral cortex takes part on processing visual information. There are three different layers that contain many things within the eyes.
Sense of hearing has two functions: hearing and balance. The functions for both of these are found in the inner ear and each consists of hair cells. These hair cells are sensitive to mechanical stimulation.
These are three divisions of the ear: the outer that has the exterior flap called the pinna and the auditory canal where the opening is lined with fine hairs and sweat glands. Located in the upper wall of the canal are modified sweat glands that secrete earwax.
The middle ear begins at the tympanic membrane but ends at the bony wall that has two small openings covered by membrane. An auditory tube permits equalization of air pressure. As this happens we sometimes hear our ears pop. The outer and middle ear has air while the inner has fluid.
The vestibular nerve takes nerve impulses to the brain stem and cerebellum. As it communicates with the brain, the vestibular nerve helps us achieve equilibrium also other structures of the body are involved. Proprioceptors are necessary in maintaining equilibrium and vision provides helpful imput the brain can act upon.

Compendium Review Chapter 11, 12

Chapter 11
The skeletal system helps support the body, protect soft body parts, produces blood cells, stores mineral and fat. It also permits flexible body movement. Compact bones are really organized and have tubular units called osteons. Bone cells called osteocytes are tiny chambers. The matrix fills the space between. Spongy bones are very different from compact bones; spongy bones are lighter but are designed for strength. Spaces between the spongy bones are filled with red bone marrow. Red bone marrow is a special kind of tissue that produces all different types of blood cells. Cartilage isn’t as strong as bones but it is a lot more flexible. It has no nerves, which is why it’s great for padding joints where stress movement are harder.
Three different types of cartilage: Hyaline, which is firm and kind of flexible. Fibeocartilage is stronger than hyaline cartilage because the matrix contains wide rows of thick, collagen fibers. Elastic cartilage is more flexible than hyaline cartilage because the matrix contains mostly elastic fiber.
There are many different types of cells that are involved in bone growth, remodeling and repairing. Osteoblasts are bone forming cells. They secrete organic matrix of bone and promote the deposition of calcium salts into the matrix. Osteocytes are mature bone cells formed from osteoblasts and they maintain the structure of bone.
Hormones have a major involvement in bone growth. A hormone is a chemical messenger, produced by one part of the body that acts on a different part of the body. Vitamin D is converted to a hormone that acts on the intestinal tract and it’s chief function is intestinal absorption of calcium. Growth hormone stimulates bone growth, however it will be somewhat ineffective if the metabolic activity of cells in not promoted. Particularly the thyroid hormone promotes the metabolic activity of cells. Due to an increased level of sex hormones, adolescents usually experience a dramatic increase in height. This is called the growth spurt.
Bones repairing after they break or fracture is very important and takes place over several months. Here are the four steps.
Hematoma: which is a mass of clotted blood. Blood escapes from ruptured blood vessels after the fracture and forms a hematoma in the space between the broken bones. This happens within 6-8 hours after the fracture.
Fibrocartilaginous callus: Tissue repair begins and the fibro cartilaginous fills the space between the ends of the bone. This goes on for about three weeks after the bone is broken.
Bony callus: spongy bone is converting to fibro cartilage callus to a bony callus. This then joins the broken bones together and lasts about three to four months.
Remodeling: Osteoblasts build new compact bone and osteoclasts absorb the spongy bone.
Bones of the skeleton are classified where they occur in the axial or appendicular skeleton. The axial skeleton consists of the skull, hyoid bone, vertebral column and rib cage. The axial skeleton lies in the midline of the body. The appendicular skeleton is portion forming the pectoral girdles and upper extremities and the pelvic girdle and lower extremities. Included in the appendicular skeleton bones are the shoulder, hip, arm, left and right pectoral girdles.
The skull is formed by brain case and facial bones.
Hyoid bones are attached to the temporal bones by muscles and ligaments.
The Vertebral column has 4 curvatures that aid in more resilience and strength for the upright position.
The rib cage contains the thoracic vertebral, the rib and their associated cartilages and sternum.
In the appendicular it holds pectoral and pelvic girdles and their limbs. These are bones from the shoulder and the hip.


Chapter 12
The different types of muscles that are in the muscular system are smooth muscles, cardiac muscles and skeletal muscles.
Smooth has a single nucleus or the cells are arranged in parallel lines. These muscles are located in the walls of hollow internal organs that make its wall contract.
Cardiac muscles form a wall around the heart. The fibers in it allow it to interlock at the intercalated disks.
Skeletal muscles have fibers that are tubular. These make the skeletal muscles attach to the skeleton. These muscles can be very long and run the length of the muscles.
The functions of the skeleton muscles:
Skeletal muscles support the body, make bones move, help maintain a constant body temperature, contraction assists movement in cardiovascular and lymphatic vessels and help protect internal organs and stabilize joints.
We have different types of muscles for different types of exercise. For those different activities we have muscles known as fast and slow twitch muscles. Fast twitch muscles are most helpful in sports such as sprinting, weight lifting, swinging a golf club, or throwing a shot. Fast twitch muscles are much lighter then slow twitch muscles because they lack mitochondria; they also have little or no myoglobin and have fewer blood vessels than slow twitch.
Slow twitch muscles are mostly used in sports such as long distance running, biking, jogging and swimming. These muscles tire only when they run out of energy. The reason they are so much darker then fast twitch is because they have manly mitochondria.