BIOL1101 Section 07 and 11 Study guide

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CHAPTER 6: ENERGY & ENZYMES

What is the function of ATP?

ATP's main use is to carry out the functions/work of the cell by providing the cell with energy. The ATP,high energy compund, is used to drive metabolic reactions-

--WORK-RELATED FUNCTIONS of ATP--

CHEMICAL WORK-energy needed to synthesize macromolecules

TRANSPORT WORK-energy needed to pump substances across plasma membrane

MECHANICAL WORK-energy needed to contact muscles

How is ATP recycled?

  • By going back and forth from ADP to ATP, by adding and taking away one phosphate.

-- The ATP Cycle - energy from exergonic reactions, like cellular repiration is used to make ATP (adenine, ribose sugar, and three phosphates) from ADP (adenine, ribose sugar, and two phosphates) via the ATP synthase membrane protein that is in the electron transport chain. The ATP is used to fuel endergonic reactions, like protein synthesis which remove the last phosphate from ATP to make ADP. Then the recycling process happens again.

What is an enzyme?

An enzyme is a protein molecule that can speed up a chemical reaction. This makes enzymes catalysts.

Enzymatic pathways-begins with a particular reactant, then goes through several intermediates(each metabolic pathway requires an unique and specific enzyme), then ends with a particular product(end product will not appear unless all enzymes are present and functional)


E1 E2 E3 E4 E5 E6

A->B->C->D->E->F->G

DESCRIBE THE ENZYME/SUBSTRATE/PRODUCT RELATIONSHIP AND ENZYMATIC PATHWAYS AS DESCRIBED IN THE LECTURE.

What affects an enzyme’s activity?

Things like pH, temperature, and concentrations of the substrates and enzymes.

1) Temperature - increased temperature leads to a faster reaction, however too high of a temperature can be fatal. Too high of a temperature can affect the folding of the protein which will affect the shape of the active site and therefore the enzyme's ability to bind it's substrate.

2) pH - enzymes function within a specific pH. If you raise or lower the pH too much it can be fatal. pH can affect the folding of the protein which will affect the shape of the active site and therefore the enzyme's ability to bind it's substrate.

3) SUBSTRATE concentration - can affect the enzyme activity. If there are 1000 substrates and only 1 enzyme, then it will take a long time for the enzyme to bind to all 1000 substrates to make the 1000 products. However, if there is only 1 substrate and 1000 enzymes, then the reaction will be very fast to change that 1 substrate into a product.

What is inhibition?

INHIBITION IS BLOCKING/STOPPING THE ENZYMES ABILITY TO DO IT'S JOB/FUNCTION FOR A LIMITED PERIOD OF TIME OR MAYBE EVEN PERMENANTLY...

  • This is important because the production of whatever product that enzymes produce typically needs to have some sort of a limiting control, preventing the production of too much of the product.

When substrates complexes with active site causes the active site to change shape, therefore the change shape forces the substrates to bond=INDUCED FIT MODEL

Two types of enzyme inhibition:

1.) Competitive inhibition: Both the inhibitor and the substrate can bind to the active site decreasing the activity.

2.) Noncompetitive inhibition: The inhibitor simply binds to a site other than the active site on the enzyme. This site is called the allosteric site. This causes the enzyme shape to change (WHERE= on the opposite side of the active site) and prevents the enzyme from bonding with the substrate.

3.)Feedback inhibition: the end product of a pathway inhibits the pathway's first enzyme.

How do some drugs work to inhibit cellular processes?

These drugs carry specific inhibitors that target certain enzymes which will slow/stop a specified process.

CYANIDES- inhibit enzymes resulting in all ATP production

PENICILLIN- inhibits an enzyme unique to certain bacteria

HEAVY METALS-irreversibly bind with many enzymes

NERVE GAS-irreversibly inhibits enzymes required by nervous system

CHAPTER 8: CELLULAR RESPIRATION

How does the cell break up glucose to harvest energy?

Step 1) GLYCOLYSIS - The cell breaks the glucose molecule (6 carbons) into two 3-carbon molecules called pyruvate in the cytoplasm. NADH is produced. Does not require oxygen, but does require two ATP. This step produces 4 ATP, which is a net gain of 2 ATP. The ATP is what is used to cut the 6 carbon glucose molecule into tthe two 3 carbon pyruvate molecules. Also two electrons are picked up by the two NAD molecules.

Step 2) PREP REACTION - The pyruvate molecules ARE TRANSPORTED FROM THE CYTOPLASM INTO the mitochondria (matrix). They are transported by a carrier membrane protein and by active transport.Electron enrgy is stored by the NADH molecule. THEY are converted into a 2-carbon acetyl group. NADH and CO2 are produced. This is the first time that a product is formed to exhale.

Step 3) THE CITRIC ACID CYCLE (or Kreb's Cycle) - IS A ENZYMATIC PATHWAY THAT USED THE 2-CARBON ACETYL GROUPS TO PRODUCE CO2, NADH, FADH2, and 2 ATP. Electron energy is stored in the NADH and FADH2. It occurs in the Mitochondria Matrix space.

Step 4) ELECTRON TRANSPORT CHAIN - THE ELECTRON CARRIERS (NADH AND FADH2) ARE THEN MOVED TO THE electron transport chain which is located on the mitochondrial cristae. Here, Hydrogen ions ARE REMOVED FROM THE ELECTRON CARRIERS AND PUMPED THROUGH THE THREE membrane PROTEINS TO THE INNER MEMBRANE SPACE. THIS PRODUCES AN UNEQUAL HYDROGEN CONCENTRATION GRADIENT (HIGH IN THE INNERMEMBRANE SPACE AND LOW IN THE MATRIX). THIS UNEQEUAL CONCENTRATION GRADIENT IS THE FUEL FOR THE MEMBRANE PROTEIN ATP synthase. HYDROGEN IONS FROM THE INNER MEMBRANE SPACE ARE PUSHED THROUGH THE ATP SYNTHASE PROTEIN AND THE FORCE OF THE HYDROGEN IONS PROVIDES THE ENERGY NECESSARY TO ADD A PHOSPHATE GROUP TO ADP TO MAKE ATP. H2O is A PRODUCT OF THE PROCDESS because the spent hydrogen ions combine with oxygen. Produces either 32 or 34 ATP.

OVERALL, CELLULAR RESPIRATION (METABOLISM) can produce either 36 or 38 ATP.

Where does each step in cellular respiration happen in the cell?

  • Glycolysis - occurs in the CYTOPLASM.
  • The Prep Phase - STARTS in the CYTOPLASM and ENDS in the MITOCHONDRIA'S MATRIX.
  • Citric Acid Cycle/Kreb's Cycle - occurs in the MITOCHONDRIA'S MATRIX.
  • Electron Transport Chain - occurs in the Mitochondria's CRISTAE (on the inner membrane).

In which steps is CO2 produced?

CO2 is produced in only two steps:

  • The Prep Phase: 2 pyruvates enter the mitochondria matrix, from glycolysis in the cytoplasm, where it's converted to 2 Acetyl Co A (attaches to Coenzyme A). Electron energy (as hydrogen atoms) is stored in NADH. Carbons are released as 2 CO2. Which is transported out into the cytoplasm.
  • Citric Acid Cycle/Kreb's Cycle: In the mitochondria matrix, Electron energy is stored in NADH and FADH2, these electrons carries carry energy from glucose to the next phase. Substrate-level phosphorylation forms 2 ATP. Carbons released as 4 CO2.

How is oxygen used in the production of ATP?

Oxygen is used throughout metabolism. Oxygen is necessary to combine with the breaking down carbon skeleton of glucose to produce CO2 in the prep phase and TCA cycle. Oxygen is also necessary to combine with Hydrogens to produce water at the end of the ETC.

    * (C6 H12 O6 + 6O2 -> 6CO2 + 6H20 + Chemical Energy). 
    * If there is no oxygen:
       ** Hydrogens will have no acceptors
       ** NAD+ cannot be recycled back to NADH
       ** pyruvate will not be able to enter the mitochondria in the prep phase

Compare and contrast fermentation with aerobic respiration.

AEROBIC RESPIRATION: Goes through all FOUR steps of metabolism. During glycolysis, glucose break down into two pyruvate molecules, if oxygen is present, it continues to the Prep Reaction phase where it is transported into the mitochondria matrix to the TCA cycle and ETC. Total ATPs ~36-38 per glucose molecule.

*Aerobic cellular respiration is far more effiecient compared to fermentation. (More ATP's produced).

ANAEROBIC RESPIRATION: Goes through only ONE step of metabolism. During glycolysis, glucose break down into two pyruvate molecules, if oxygen is absent, then the pyruvate cannot enter the mitochodria during the prep phase. So there is a build up of pyruvate in the cytoplasm. The pyruvate is then converted into Lactate. So, only the ATP produced during the glycolysis phase is produced here. Total ATPs ~2 per glucose molecule.

CHAPTER 36: DIGESTION & NUTRITION

Describe the flow of food through the Human digestive system?

MOUTH -food goes into the mouth where teeth MECHANICALLY break up the food AND enzymes in the saliva BEGINS THE PROCESS of breaking down carbs in the food. The tongue helps mix the broken food and saliva together to make a bolus which is then swallowed.

PHARNYX - where the food tube and breathing tube meet in the back of our throats. (directly above the esophagus)

  • contains the epiglottis which closes off the trachea so that food will not get into the lungs and air will not get into the stomach.

ESOPHAGUS -esophagus is just a part of the digestive tract where food moves down to the stomach by peristalsis.

PERISTALSIS is the rythmical contraction of the digestive tract to move the bolus from the mouth all the way to the anus.


STOMACH -stomach lowers the pH (TO pH2) to break down proteins (by unfolding them/breaking the bonds which give them their tertiary structure) AND SECRETES pepsin AN ENZYME THAT BREAKS DOWN PROTEINS TO THEIR SIMPLIST COMPONENTS (AMINO ACIDS).

SMALL Intestine -food is THEN moved to the small intestine where the macro molecules are completely broken down INTO THEIR monomers AND are absorbed to go into either the blood (protein and carbs) or into the lymph system (lipids). This is where the food gets digested and it is also where the needed nutrients are absorbed. In the first section of the small intestine is where the most action occurs. Here is where the accessory glands drain in their fluids to aid with this process.

  • LIVER-the liver(accessory gland) makes bile to be stored in the gall bladder.
       **Bile is what allows the fat to "dispurse in water".

  • Gall BLADDER-(accessory gland) transports bile that was produced in the liver to the small intestine.
      Occurs when a bolus enters from the stomach. 
  • PANCREAS-(accessory gland) secrets a fluid to bring the bolus into a more normal pH.
     It also secretes enzymes to COMPLETELY break down THE macromolecules to their monomer form.
**Carbohydrates get broken down into monosaccharides.
**Proteins get broken down into amino acids.
**Lipids get broken down to glycerol and fatty acids.

LARGE INTESTINE- the REST OF THE BOLUS THAT IS NOT ABSORBED BY THE SMALL INTESTINE IS THEN MOVED VIA PERISTALSIS TO THE large intestine. IT IS HERE THAT WATER IS REabsorbed INTO THE BODY WHICH HELPS TO COMPACT THE FECES. ALSO, salt and a few vitamins ARE ABSORBED IN THIS PART OF THE DIGESTIVE TRACT.

RECTUM-rectum gets rid of the solid waste THROUGH THE ANUS.

What is the function of the liver, gall bladder and pancreas in this process?

LIVER - makes the bile and sends it to the gall bladder. the hepatic portal vein which is also located in the liver transports nutrients from the intestines. the liver removes and adds materials to the blood and deposits bile in a duct.

GALL BLADDER - The gall bladder stores the bile that is sent from the liver, until it is needed for digestion. Bile is then sent to the small intestine to digest fat. water is reabsorbed by the gall bladder making the bile a thick mucus like material.

PANCREAS - Pancreas has three functions- a) secretes hormones that regulate blood glucose levels, b) produces enzymes that break down digestible foods, carbs, proteins and fats to monomers. c)produces the fluid that increases the pH (which is at 2 because of the stomach acid) back to normal (~7).

How are carbohydrates, proteins, and lipids broken down and absorbed?

CARBOHYDRATES - Carbohydrates begin to be broken down in the mouth with an enzyme that is in saliva. In the small intestine, the carbs are completely broken down by enzymes. Glucose and other monosaccharides are the products of this digestion. The glucose and other monosaccahrides are then actively transported/absorbed into epithelial cells of the small intestine. The monosaccharides are then absorbed into the blood stream.


PROTEINS - When the proteins reach the stomach, they begin to break down when they come into contact with pepsin and HCl. The protein reacts with the pepsin and HCI in the stomach by unfolding/breaking the bonds which hold the protein in it's tertiary structure. The protein then unfolds to the primary structure which can then be broken down further by the enzyme pepsin. When these amino acids reach the small intestine, the are completely broken down into amino acids because enzymes SECRETED BY THE SMALL INTESTINE assist in this process. The amino acids then get absorbed by the epithelial cells and into the blood stream.


LIPIDS - The lipids begin to break down into their monomer form in the small intestine by bile. Bile emusifies the fat molecules which breaks down triglycerides into glycerol molecules and individual fatty acids. These monomers are absorbed into the epithelial cells where they are then absorbed into the lymph system. Where they are put inside of proteins so that they can safely travel into the blood stream.

How is a well-rounded diet important for a body to function?

if you don't have a well rounded diet, you won't consume all the vitamins and necessarry for your body to function properly. If you do not consume enough vitamins a lot of different symptoms will begin to develop. If your body does not have enough calcium, then you can develope osteoperosis. Hypertension can be caused if your body has to high of an intake of salt. --Having a well-rounded diet is very important because if you do not have one it can shorten your life span or make your life difficult by having a heart attack or diabetes.

Describe the function of vitamins and minerals.

Vitamins

  • Thiamine (B1), water soluble vitamin, used for carbohydrate metabolism (is part of the molecule Acetyl-CoA).
  • Riboflavin (B2), water soluble vitamin, used for energy metabolism (is the F in FAD).
  • Niacin (B3), water soluble vitamin also used for energy metabolism (is the N in NAD).

Minerals Major Mineral Functions: Strong bones, teeth, muscle contration, nerve conduction, ph and water balance, and protein synthesis.

Trace mineral Functions: Strong teeth, heal and tissue growth

CHAPTER 38: EXCRETION

What is the importance of regulating fluids within the human body?

Helps to keep the pH balanced.

Helps with the absorption of nutrients through the blood and the disposal of nitrogenous waste and toxins through the urine.

Maintains water in the body for it to correctly function: Either by addition (Drink, Food, Metabolism) or disposal (Excretion, Respiration, Sweat)


regulates the actual concentration of the fluids in your body.

Why do we want to excrete these fluids?

The secretion of these fluids helps to maintain homeostasis.

  • All things can be toxic if the levels of them get to high in the body, so a certain number of them are expelled until the right amount is present.

What are the components of urine?

-AMMONIA - The result of the breakdown of amino acids and nucleic acids. Toxic at high levels.

-UREA - a compound converted from ammonia, less toxic than ammonia, produced in the liver. Can be concentrated without toxic repracussions.

-URIC ACIDa nitrogenous waste product.

-HYDROGEN IONS - Hydrogen ions are responsible for pH in the body so by excreting them, you can regulate the blood pH

Where do the components of urine come from?

They come from the blood that is filtered by the kidneys. The nitrogen wastes such as Ammonia, urea and uric acid come from proteins and will always be excreted from the body. Other molecules such as glucose, salt (sodium, chlorine, potassium), vitamins, water, bicarbonate and amino acids are removed from the blood as well. However, if the molecule needs to return to the body they can be reabsorbed in the nephron.

Describe the basic structure of the excretory system.

The body's organs associated with the excretory system:

KIDNEYS – They are located below the diaphragm, on either side of vertebral column. Each is connected to a ureter which led to the bladder.

NEPHRON - tiny tubules, loopy structure with in the kidney that produces urine. located in the renal cortex and some in the renal medulla.

FILTRATION-remove fluid and small molecules from blood(blood filtered in glomerulus)

RE-ABSORPTION of important molecules-put water,vitamins, amino acid, and sodium(etc..) back into the blood stream

   *urine is concentrated by the reabsorption of water on the descending portion of the "loop" 
   * During the ascending portion of the "loop", salt leaves by active transport.
       

SECRETION- blood secretes ammonia, uric acids, and hydrogen ions

                *want to get rid of everything else in this stage


URETERS - a duct transport the urine. Transport from the kidneys to the bladder

BLADDER – stores urine. Transport from the ureters to the urethra.

URETHRA – passes urine out of the body. It is a tube between bladder and exit. Females have shorter urethra than men. Urine travels through urethra, and out of the body.

CHAPTER 34: CIRCULATION & CARDIOVASCULAR SYSTEMS

Trace the flow of blood from the body to the heart and lungs and then back to the body.

Oxygen-Poor blood returns to heart from everywhere(the whole body); It enters the right atrium. There the right atrium pumps the blood through the tricuspid valve (atrioventricular valve) to the right ventricle. Lastly the right ventricle pumps blood though the pulmonary SEMI-LUNAR valve to the lungs where it does gas exchange.

From the lungs, THE NOW oxygen-rich blood enters the left atrium. The left atrium pumps the blood through the bicuspid valve (atrioventricular valve) to the left ventricle. The left ventricle pumps the blood though the aortic SEMI-LUNAR valve to the rest of the body like the liver, intestines, kidneys,and every where else.

How can an unhealthy lifestyle affect the vessles of the heart?

blood carries nutrients throughout the body, so if your diet is high in fat, it will collect along the lining of your blood vessels and cause them to harden. Too much salt or protein intake can affect the pH of the blood or cause major blood clotting inside the vessles. If blood clotts to much in one spot then it will slowly close off the vessel causing a heart attack.


WHAT ABOUT INCREASED SALT OR PROTEIN (LIKE ATKIN'S DIET)?

What elements are in blood?

1) Red Blood Cells

  -help transport oxygen from lungs to tissues and carbon dioxide from tissues to lungs. 
  -lack organelles and a nucleus
  -disk shaped with thick rim and thin layer
  -contain hemoglobin
  -120 day life span
  - rely on anaerobic respiration to produce ATP.
  - regulates body temperature
  - buffers the body's pH


2) White Blood Cells (5 kinds)

  -help fight infections
  -larger than red blood cells
  -contain a nucleus
  -lack hemoglobin
  -NAMED: 1)neutrophils, 2)eosinophils, 3) basophils, 4) lyphocytes, 5) monocytes


3) Platelets

  -cell fragments without nuclei that are disk-shaped that help in clotting


4) Plasma containing things such as:

  -the liquid portion of blood
  -the molecules in plasma have several different jobs including blood water ratios,
    balancing pH level, and blood clotting, maintaining the osmotic pressure.
   ** Oxygen
   ** Carbon Dioxide
   ** Nutrients
   ** Nitrogenous Wastes
   ** Water
   ** Hormones
   ** Glucose
   ** NaCl
   ** electrolytes

And what is the function of the elements found in blood?

1) Red Blood Cells- transport Oxygen from the lungs to the tissues. Transports Carbon Dioxide from the tissues to the lungs.

2) White Blood Cells- Help fight infection and disease.

3) Platelets- stick together to help form blood clots, initiate formation of a clot dissolving enzyme, and secrete proteins that promote blood clotting.

4) Plasma- makes the blood the right consistency maintains osmotic pressure, buffers the body's pH.

   **Oxygen-aid in cellular respiration
   **Carbon Dioxide-end product after metabolism
   **Nutrients- capillaries exchange nutrients from blood to cells. 
   **Wastes- Wastes taken into the blood to be cleaned out in the kidneys during excretion. 
   **Water- raises or lowers the blood volume and aids in transporting molecules.
   **Hormones- help in the metabolism processes.
   **Glucose- taken from blood for metabolism. 
   **NaCl- maintains pH level of blood at 7.4 and helps water enter capillaries.

CHAPTER 37: RESPIRATORY SYSTEMS

Trace the path of air, how it moves from the mouth to the lungs and back out again.

1.) Air (O2) enters through the nostrils or the mouth and particles are filtered out here.

2.) Air (O2)then goes through the upper respiratory system. Here it is warmed and humidified.

3.) Air (O2) then goes through the pharynx and the trachea and continues to be warmed and humidified. The air is the temperature of the body by the time it reaches the lungs and the humidity will equal 100%.


4.) Then passes through the bronchus and bronchiole located in the lungs.

5.) Arrives at the alveoli. In the alveoli the exchange of Oxygen and CO2 molecules occurs. The CO2 from the blood is exchanged with the oxygen in the lungs. The aveoli are wrapped in capillaries, these capillaries bring oxygen poor blood to the aveoli, diffuses CO2 and pickup oxygen with the help of hemoglobin in the red blood cells.

6.)Then the Co2 is breathed out starting at the alveoli to the Bronchiole, to bronchus, to trachea, to pharynx, to nasal cavity, to nostril, and out.

What is the role of CO2 in the stimulation of the breathing rate in humans?

Breathing is stimulated by the amount of hydrogen and CO2 in the blood which affects the pH. If pH in the blood is not exactly correct then the body will suffer. So to even out the pH, hydrogen, CO2 and other unneccessary stuff is removed by breathing out and is replaced by breathing in oxygen.

Discuss TWO potential disorders of the repiratory system.

1) Common breathing problems take place in the aveoli of the lungs. The more surface area on the inside of the aveoli the better the gas exchange. The alveoli can fill with fluid, pus, bacteria or burst and fuse together causing the process of gas exchange in the lungs to be difficult. Also due to bacteria and fibrous tissues, the elasticity of the lungs can be reduced.

2) Bronchioles can also be irritated which makes them constrict because of muscle spasms which can reduce the amount of air inhaled and exhaled. The airways can also be filled with mucus and/or pus which can also reduce breathing. Airway inflammation. This can cause blockage of the path of air, restricting the amount that reaches the lungs. Can lead to excess CO2 in the body and lack of Oxygen because transfer rates will slow.

CHAPTER 43: REPRODUCTION

Trace sperm production to fertilization of the egg.

Sperm is produced in the testes which are housed in the scrotum. The gonads is where this is located. They are then matured in the epididymis. Then they are propelled into the vas deferens by muscle contractions. In the testes there are three seminiferous tubules where the sperm is made. A sperm can be divided into three parts the head, where the DNA is, the mid peice and the tail. Several hundred million sperm can be ejected at one time. There are three glands that make the seminal fluid. then finally travels out through the urethra of the penis. The sperm then travels up the vagina, into the uterus andthen up to the fallopian tubes where it will fertilize an egg.

Trace egg production to fertiliztation.

All females are born with a large number of eggs. These eggs have only gone through meiosis one and must go through meiosis two before they are used in ovulation. No eggs will be made with meiosis one after birth. The (oocyte) egg leaves the ovary to the fallopian tube where fertillization occurs. Then the ciliary movement moves the zygote to the uterus where the embryo embraces the egg in the uterine lining (endometrium). The stuff around the egg develops is released if you get pregnant. This left over stuff (corpus luteum) then regulates the hormones neccessary for pregnancy. If the woman does not get pregnant then the corpus luteum is broken down to its monomers.

NEED TO DISCUSS THE PROCESS OF OVULATION HERE... THERE ARE 5 STEPS IN HOW EGGs ARE RELEASED.

CHAPTER 39: NERVOUS SYSTEM

What are the functions of the human nervous system?

  • Recieve sensory input - WHAT DOES THIS MEAN?
  • Perform signals based on the input - WHAT DOES THIS MEAN?
  • Generate motor output - WHAT DOES THIS MEAN?

Central Nervous System - (includes brain and spinal cord)

Peripheral Nervous System(contains craniak nerves and spinal nerves) - gather info from sensors and conduct decisions to effectors

  • Somatic System -
  • Autonomic System - part of peripheral system. maintains homeostasis. Also regulates heart rate respiration rate, persperation pupils to name a few.
    • Sympathetic System - become active during times of stress, determine the resonses such as "fight or flight"
    • Parasympathetic System - determines when the body needs rest and regulates the digestion process

What is the basic anatomy of the brain including: cerebrum, thalamus, cerebellum, brain stem, corpus collosum and ventricles?

Cerebrum - (largest portion of the brain)communicates and coordinates the activity of the body and other parts of the brain

thalamus - large portion of grey matter cells, part of brain located at the top of the brain stem. Revieve auditory and visual sensory signals. sends sensorys signals to the cerebral cortex.

cerebellum - (muscle coordination) receives sensory from the eyes, ears, joints, and muscles

brain stem - consists of the midbrain, pons and medulla oblongata, the back bottom of the brain. Sends its info from the nervous system and spinal cord to the upper parts of the brain.

corpus collosum - Bundle of nerves that connects the left and right hemishperes of the brain.

ventricles - Brain ventricles or any ventricle (e.g. Right/Left ventricle in the heart) is a "cavity" (empty space that can be filled). In the brain the ventricles are filled with Cerebral Spinal Fluid (CSF).

         Three main purposes of CSF are:
              1. Buoyancy (prevent damage or pressure problems) 
              2. Protection (from shocks and jolts) 
              3. Chemical stability (place to empty cellular wastes)

Describe the structures of the different types of neurons.

  • Motor Neurons - pass impulses from the Central Nervous system to the muscles or glands. cell body with organelles and nucleus. dendrites, axon covered with a lipid coation called myelin sheath and axon terminal that attaches to muscles.
  • Sensory Neurons - pass information from the body to the Central Nervous System. cell body with the organelles, two axon with myelin sheath. one axon goes to skin or tissue where the sensory receptors are located, the other axon goes to another leads to the central nervous system.
  • Interneurons - are only in the Central Nervous system and pass on information only to other neurons. cell body, one axon not covered by a axon sheath, and many dendrites located off the main cell body which are used to tranmit information.

How does a neurotransmitter send signals?

Transmition is sendind signals by releasing neurotransmitter molecules from a dendrite in the synaptic cleft to another neruon's cell body. Where they bind to receptors which cause a reaction.

WHAT ARE THE RECEPTORS?

CHAPTER 41: MUSCULAR/SKELETAL SYSTEM

Given a picture of a skeleton, name the major bones.

  • Skull: protects the brain
  • Vertebral column: supports head & neck; protecks spinal cord & spinal nerves

Cervical: Neck Thoracic: Thorax Lumbar: Small of Back Sacral: Sacrum Coccyx: Tailbone

  • Sternum: what the ribs connect to
  • Ribs: protects heart, lungs, and help us breath. 12 pairs of ribs

first 7 pairs are true ribs (directly connected to the sternum) 5 pairs are false ribs which do not connect directly to the sternum.

What is the function of the skeletal system?

  • Supports and protects the body
  • Permits movement
  • Provides resistive foundation for muscles to act agianst

Compact bone - for support. The unit of structure is refferred to as an osteon

  • Spongy bone - makes red blood cells, which is also known as stem cells and spaces contain marrow
  • Storage for Calcium and Phosphate.

How do muscles contract?

Many Myosin protiens walk along the Actin filament, using ATP, by binding with a an Actin molecule, pulling it forward by flexing, and then releasing the molecule by relaxing which turns the ATP to ADP. Then,the Myosin head binds with a new Actin molecule further up along the filament, again pulling it forward. This process is repeated many times by many myosin heads along the Actin filament.

CHAPTER 42: ENDOCRINE & INTEGUMENTARY SYSTEM

What is the function of hormones in the body?

Hormones are used as a communication device to activate a process within the body. Far away from initiation point, not just in one cell. The communication within the body is done through chemical signals that are within the blood.

What are the functions of the pituitary gland?

The pituitary gland is located in the hypothalamus. It gives off signals to regulate the environment of the body, such as pH. Delivers these signals through the release of hormones.

How is blood sugar regulated?

  • the pituitary gland signals the pancreas to either secrete glucagon to release sugar back into the blood or insuline to get rid of sugar in the blood to maintain blood sugar levels.
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