Thursday, October 29, 2015

Digestion and Nutrition

My Daily Menu






















  1. Explain why the menu of food choices you made is nutritious, meaning the food choices follow the government's recommendations for Calories and nutrients.

    I tried to make choices that are relatively reflective of what I eat. I am vegan, so substitute tofu and tempeh, etc for the dairy and meat choices (I think this would've helped with the sodium issue, as well, as these food are much lower in sodium then cottage cheese, etc). I got enough calories pretty easily, as well as proteins and carbohydrates, and stayed under the DV for fat, etc, although in my own diet I like to add healthy fats like avocado and Flax oil.

  2. How does a 2 000 Calorie daily menu compare to your recommended Calorie intake amount on the chart? What would you do to your 2 000 Calorie menu to make it better match your recommended Calorie intake?

    My recommended intake is between 2000 and 2200, which is about where I ended up. However, I feel like when we are listening to our bodies, our caloric needs will vary day-to-day.

  3. How can you use the Nutrition Facts label to make healthy decisions?

    The labels help to make very clear how much sodium and sugar are in various products. I also look closely to see how many ingredients are listed, and how many of those ingredients sound like they were produced in a chem lab.

  4. Did the menu you created contain the foods you like to eat? Explain why or why not.

    Yes, however my own diet has much more variety.

  5. Do any of the items you selected provide more than 30% in any nutritional area? If so, which foods and which nutrients? Why did you choose those foods?

    The grains added a lot. In a veggie diet, eating a wide variety as opposed to one big chunk of a particular food, seems more helpful, though. However, use of nutrient-dense foods such as unsalted nuts and whole grains such as quinoa helps us to meet our bodies' nutritional requirements.

  6. What did you notice about the nutrients in fast foods?

    I didn't even go there. I haven't eaten at a fast food retaurant in ten years. Seriously. That stuff'll kill you.

  7. What did you notice about the food group icons in your Daily Meals area? Did you favor a specific food group? Explain.

    I went for fruits and veggies a lot. They allow us to eat quite a bit and feel full without adding unnnecessary calories. They also add important vitamins and minerals.

Sunday, October 25, 2015

Nervous System

Nerve Histology


 Nervous tissue has a similar arrangement to muscle tissue. Each axon is surrounded by connective tissue, and then bundled into a larger group, a fascicle, which itself is surrounded by connective tissue. This is then arranged together into the larger working nerve unit, also surrounded by connective tissue. The endoneurium surrounds each nerve cell, the perineurium surrounds each fascicle, and the epineurium surrounds each nerve as a whole. In muscle tissue, these connective tissue sheaths are the fascial surroundings of the muscle fiber, fascicle, and whole muscle.
Nerves connect to the spine via thicker ganglia areas. As the nerve travels through the body, various neurons innervate specific areas and the bundle as a whole thins.
Multiple Sclerosis is a serious disease that affects the myelin sheathing of neurons. The ability to transmit signals becomes progressively impaired. People with MS have symptoms that can vary day-to-day, but generally include sensitivity to temperature extremes, muscle weakness, vision problems, and difficulty coordinating movements.

 Anatomy of a Neuron
 
 Sensory neurons carry information from their specialized receptors to the CNS. They are located in the skin, and throughout the body, including within organs and around blood vessels. They can sense pressure, temperature, pain, etc. and are the information-carriers that keep the CNS apprised of our internal and external environments. Motor neurons innervate skeletal and smooth muscle, and carry the CNS's instructions and reactions to all parts of the body. Interneurons integrate the information between the two, ensuring that the appropriate response is matched with the appropriate stimulus. They are also the coordinators of spinal reflexes.

Reaction Time Rulers

Visual Stimulus
Auditory Stimulus
Tactile Stimulus
Person 1
Person 2
Person 1
Person 2
Person 1
Person 2
Trial 1
R-3” 
L-2.25”

R-3”
L-6”
R-2”
L-1”
R-5” 
L-2”
R-13.5” 
L-10”
R-3” 
L-6”
Trial 2
R-1”
L-3.25” 

R-5”
L-14”
R-2” 
L-5.75”
R-3.25” 
L-2.5”
R-2” 
L-8”
R-2.5” 
L-3.75”














                                                                                                                                                                                                

My hypothesis had been that visual stimuli would process faster as a large part of our brains are dedicated to visual processing. Visual stimulus did work well for me, but not so much with my partner, who has some visual impairments (possible explanation). My quickest reaction times were visual and audio, and she did well with audio and tactile. To be honest, beyond her slight visual issues, I have no explanation for why we differed. Perhaps genetic tendencies, or training of certain stimuli over the years makes a difference. We also might both be different about how we administered the test. Having a third person test both of us might have given better data.
Nerves take a bit to create a reaction because the sensory input must travel biochemically along a sensory nerve to the CNS, where it is processed by interneurons and sent either back out to the appropriate muscles (a reflex) or up to the brain and then back down the spinal cord and out. All this is done through action potentials. While they do not take long to generate, they do take some time, and therefore we don't have instantaneous reactions, even with reflexes.
My hypothesis was not supported, and this data would lead me to create a more definite experiment.



                                                Somatic division                                                                              Autonomic division


Sympathetic
Parasympathetic
Function
Works with Skeletal Muscles
Arousal, mental acuity, flight-or-fight
Relaxation, repair, digestion and basic functions
Neurotransmitter
Acetylcholine
Norepinephrine
Acetylcholine




 

Sunday, October 18, 2015

Immune System

Part 1: Erythrocytes and Leukocytes~
Erythrocyte

Neutrophil


Basophil

Leukocytes & Their Functions

Basophils-.5% Rare
Theses histamine-containing granular leukocytes help initiate the inflammatory response of the body. When tissues are injured, basophils secrete histamine, causing adjacent blood vessels to leak plasma, bringing nutrients, cells and chemicals necessary for repair to the damaged area.

Eosinophils-2%-4%
These granular leukocytes defend against large parasites, such as hookworms and tapeworms(ewwwww!)by bombarding them with digestive enzymes.They also release chemicals that moderate allergic reactions.

Lymphocytes-30%
These agranular leukocytes are found in the spleen, tonsils, lymph nodes, and thymus gland, in addition to the blood stream. B lymphocytes create plasma cells that produce antibodies, and T lymphocytes target specific threats such as cancer, bacteria and viruses.

Monocytes-5%
The largest of the WBCs, these agranular leukocytes make their way out of the bloodstream and live in various tissues. Depending on where they end up, they become various macrophages that engulf nonself cells and cell debris. They increase with the presence of chronic infections.

Neutrophils-60% Most Common
Neutrophils are the first on the scene of an infection, and their numbers increase drastically during acute bacterial infections. These granular leukocytes surround and engulf the bad guys, especially bacteria and a few fungi.
 
Part 2: Lymphatic System
 
Tonsil
 
The lymphatic system is a sister system to the cardiovascular system. Interstitial fluid is gathered up in lymph vessels which are processed through leukocyte-containing lymph nodes. Once the lymph is "cleansed", it continues along into the right lymphatic duct or the thoracic duct, where it meets up with the subclavian veins and is returned to the bloodstream. The flow of lymph is very similar to the flow of returning blood through the veins, with muscular contraction helping the process along. In addition, the spleen removes old and dead red blood cells from the circulatory system, and stores the cleanse blood so that the body can call on it in times of need. The lymphatic system also carries the fats and fat-soluble vitamins absorbed from the digestive tract into the circulatory system for distribution to cells. 
 
Part 3: Nonspecific Body Defenses
Skin-The Integumentary System defends the body from invasion by forming a tough outer barrier that is difficult for microorganisms to breach. The dead, outer-most cells of skin are formed of keratin, and is a difficult membrane to breach. Our skin is constantly being sloughed off, which also sloughs off any pathogens that have been living on the skin. Our skin also maintains an acidic pH which is difficult for pathogens to exist in.
Cilia- Cilia arise from epithilial tissue and exist in our airways where their constant upward motion helps to sweep mucus (and therefore trapped pathogens) into the throat where we expel it, or it is swallowed and eliminated through the digestive system.  
Phagocytosis
 1) Phagocyte captures bacterium.
2) Phagocyte surrounds bacterium with plasma membrane.
3) Bacterium is closed off inside a vesicle.
4) Lysosomes, containing powerful enzymes, fuse with bacterium's vesicle.
5) Lysosome enzymes digest and destroy bacterium.
6) The waste products are expelled from the phagocyte.
Phagocytic Cells-Neutrophil & Macrophage
Inflammatory Response
All tissue injuries trigger inflammation, characterized by redness, warmth, swelling, and pain. Damaged cells release chemicals that stimulate mast cells (connective tissue cells) to release histamine (basophils secrete histamine as well). Histamine causes nearby capillaries to dilate, giving enough space to allow phagocytes to get through to attack foreign cells and destroy damaged cells. Some phagocytes return to the lymph system and stimulate lymphocytes, beginning the specific defense system response. Complement proteins also leak into the area and help by marking pathogens for destruction or destroying them personally (see below). Vasodilation allows blood to seep into the area, which makes it red and also warm-these warmer temperatures heighten phagocyte activity. Swelling is caused by fluids leaking through capillaries, which dilute pathogens and toxins and brings in clotting proteins that create a fibrin mesh that walls off the damaged tissue. It also carries extra oxygen and nutrients for healing, and washes away dead cells, pathogens and debris.Swelling presses on nerve endings. This combined with sensitizing chemicals from inflammation, creates pain, and slows us down to heal.
 

Complement Proteins Killing Bacterium
 There are at least twenty plasma proteins that assist in defense of the body. When they are activated, they seep through the capillaries and create a cascade effect, activating more and more proteins. Some join together to form large protein complexes that pierce holes in the cell walls of bacteria. This allows water and salts to seep in, exploding the cell.
 
Part 4:Specific Body Defenses
The major histocompatibility complex is a set of proteins that are on the surface of our cells. Our MHC proteins are unique to us, and are used as a kind of fingerprint whereby our immune cells can recognize "self" cells.
Antibody Structure
 
 There are five classes of antibodies-IgG, IgM, IgA, IgD, IgE.
Clonal Expansion
 When an antigen-presenting cell activates a T cell, the T cell clones itself with the identical receptors. Some of these clones become memory cells for the next time around. The rest continue to clone and then attack the target cell.

Interferon is secreted by virally infected cells and diffuses to healthy cells. It binds to their cell membranes and causes them to produce proteins that interfere with viral protein synthesis, making it harder for the virus to infect the healthy cells.
 
Cell mediated and antibody mediated immune responses are brought about by lymphocytes. B cells are in charge of antibody-mediated immunity. They produce antibodies that bind with specific antigens and neutralize them. This works best against viruses, bacteria, and foreign molecules that are blood and lymph soluble, as that is where antibodies circulate. T cells are in charge of cell-mediated immunity, where T cells directly attack foreign cells or help with other immune responses by releasing proteins that coordinate T cells, B cells, and macrophages. This works best with parasites, fungi, bacteria, cancer, and foreign cells. 
 
Active and Passive Immunization are both ways medical science helps us to stay well. Active immunization is done with vaccines created from dead, weakened, or synthesized pathogens. They create a primary immune response in the body, which confers long-term immunity through the creation of memory cells. It must be done before the disease is actually contracted. An example is the diphtheria vaccine. Passive immunization can be used once an infection has already occurred and it uses antibodies from a human or animal that already has immunity. it confers short-term immunity as no primary immune response occurs in the body. It can also occur naturally through the placenta or breastfeeding. An example is the tetanus shot.