MP2 Powerpoint Living Environment
Period 4 12/07/12 • Attendance • Test today • No electronics during or after the test. • Sit facing front. • No talking or disturbing others. • Raise your hand if you have a question • Although – please don’t ask me to explain how to do a question!
Homeostasis a.k.a. Dynamic (ENERGY!) Equilibrium (BALANCE!) -internal(inside) -external(outside) -Homeostasis -temperature -salt and water -glucose(simple sugar; C6H12O6) -temperature -98.6°F -positive feedback=labor contractions!
“OFF” “ON” heat saved, heat made, blood warms hair up, vasoconstriction, shivering
“OFF” “ON” heat lost, blood cools hair down, vasodilation, sweating
insulin • lowers • carbohydrates • glucose • cellular respiration
What is hyperglycemia?Hyperglycemia (hi"per-gli-SE'me-ah) is an increase in plasma glucose (blood sugar). It can turn into a complex medical condition -- diabetic ketoacidosis (ke"to-as"id-O'sis) and coma -- if it's not treated on time and adequately. Hyperglycemia is usually the first sign of diabetes mellitus. Symptoms of hyperglycemia are • polyuria (pol"e-YUR'e-ah) (excess urine) • polydipsia (pol"e-DIP'se-ah) (thirst) • polyphagia (pol"e-FA'je-ah) (excessive hunger)
What is hypoglycemia? Hypoglycemia (hi"po-gli-SE'me-ah) is a low level of plasma glucose (blood sugar). It's a dangerous condition because glucose is the major source of energy for the brain. Lack of glucose, like lack of oxygen, produces brain damage or even death if the deficit is prolonged. Hypoglycemia starts to cause these symptoms: sweating, tremors, anxiety, hunger, dizziness, headache, cloudy vision, confusion, abnormal behavior convulsions, loss of consciousness.
“OFF” (insulin stopped) “ON” (insulin released) sugar uptake into cells, stored as glycogen normal blood sugar
“OFF” “ON” less ADH secreted, less urine water levels normal
Enzymes: Who needs them? • You do if you like detergents, bread, baby food, beer, fruit juice, cheese, candy, rubber, paper, or film because enzymes are needed to make these products! • You do because living things can’t live without them and you, my friend, are a living thing.
A tasty and delicious example of an enzyme at work… • Complex carbohydrates like starch and glycogen are broken down into the simple sugar a.k.a. monosaccharide glucose in your mouth with the help of the enzyme salivary amylase. I guess spit’s fantastic! A carbohydrate made of glucose subunits! salivary amylase Glucose, a simple sugar.
A not-so tasty and delicious example of an enzyme at work… • The enzyme lactase, with the help of water, breaks (digests) the disaccharide lactose down into 2 monosaccharides─ galactose and glucose. Many adults, however, don’t make enough lactase so ingesting dairy causes symptoms like painful gas and diarrhea. Uh-oh!
Enzymes are everywhere!even in a bug’s butt luciferase • luciferin + ATP oxyluciferin + AMP + light • The above chemical equation represents a biochemical process that occurs in the abdomen of the firefly called bioluminescence. Without the enzyme luciferase to push the chemical reaction along, the insect would not glow and, therefore, would not be able to attract a mate. Photinus greeni finds a mate thanks, in part, to the enzyme luciferase!
How do enzymes keep us alive? • An enzyme is a protein that catalyzes, or speeds up, a chemical reaction. Without enzymes, many of life’s vital biochemical processes would happen too slowly or not at all! Think about a little kid on a swing. Without a push, they aren’t going to get going. With a few pushes, though, that kid can swing on their own. The enzyme is what gives the biochemical process the push it needs to get going.
Enzymes are catalysts. • Enzymes are biological catalysts. A catalyst makes a chemical reaction go faster but is not changed or used up by the reaction. The reason the enzyme’s name is written above the arrow in a chemical equation is because it is the only molecule not changed during the chemical reaction a.k.a. biochemical process. • This means that the same enzyme can be used over and over again which saves the body energy because it doesn’t have to make new enzymes each time. Way to work smarter, not harder, body!
What’s a lock got to do with it? • You have 1000s of enzymes in your cells and each one speeds up a different chemical reaction a.k.a. biochemical process. • An enzyme’s shape determines what substrate it acts upon. This is called specificity and is illustrated by the lock-and-key model.
Enzymes: They Look a Hot Mess But They’re a Specific Shape • Here is an image of the restriction endonuclease enzyme EcoRI which digests DNA. • Here is an image of the enzyme lactase which digests milk sugar.
So what might an enzyme do during a chemical reaction? • An enzyme grabs a substrate (the molecule that the enzyme changes) and breaks it apart. • The active site is where enzyme and substrate connect. • In this example, the name of the reactant is sucrose. The names of the products are glucose and fructose. • This is a breakdown a.k.a. digestion reaction and it releases energy when bonds are broken!
carbonic anhydrase CO2 + H2O Are digestion reactions the only type of reaction? • No! There are also synthesis reactions where an enzyme makes a big molecule out of 2 smaller ones. This uses energy! Here’s a synthesis reaction taking place in your blood that happens 10 million times faster thanks to the enzyme:
How do enzymes speed up reaction rates and what affects them? • Enzymes work by lowering the activation energy─ the amount of energy needed to push a chemical reaction forward. • Each enzyme works best at a certain temperature, pH (acidic, neutral, or basic), and concentration (how much enzyme or substrate is around). Your body’s enzymes work best at normal body temperature and a neutral pH except for enzymes in the stomach and vagina which have adapted to an acidic environment.
Do enzymes always work? • Sometimes high temperature or extreme pH (strong acids and bases) may affect the shape of an enzyme. • This effect is called denaturation and can make the enzyme less effective and possibly useless. • Just as a melted house key won’t open your door, a denatured enzyme won’t work on its substrate! Good luck maintaining homeostasis if that happens! It just may be the dun-dun-schnipple!
MACROMOLECULES OR WHY DO WE EAT?
FOOD 1. Provides energy for all of the body’s functions, from the beating of the heart & the elimination of wastes to the transmission of electrical & chemical signals in the nervous system. Food is the fuel that contains energy from the sun, originally captured & stored by green plants, then passed along to fruits, seeds, & animals. Humans eat these foods & burn the fuel they contain to release the stored solar energy. As long as we live, we have to eat and eat often! Text from: Eating Well for Optimum Health Andrew Weil, MD
2. Food provides the building blocks of our bodies. In the same way that you can’t build a lego castle without lego pieces, you can’t build the parts of your body without certain nutrients.
The food we eat contains nutrients. Some of these we disassemble and then reassemble for parts we need. (Like breaking down the lego castle to build a lego ship instead.) Some nutrients are essential because we can’t manufacture these on our own. Macromolecules are these nutrients.Macromolecules come in 4 types. All macromolecules are organic which means they are produced and made by living things. Carbohydrates Lipids Proteins Nucleic acids
CARBOHYDRATES All carbs are made up of only 3 elements: Carbon, hydrogen, & oxygen. All carbs look like this in their simplest form. By the way, this is called a simple sugar or monosaccharide. mono = one saccharide = sugar But remember I said that you can use these guys as building blocks. Well if you put two of them together you get this. It’s called a disaccharide. Di = two
And if you string a bunch of monosaccharides together you get a polysaccharide. They look like this. Luckily they have the same general shape (hexagonal) and they are all carbohydrates .
WHY ARE CARBOHYDRATES IMPORTANT? They are the body’s preferred choice of energy . Just like your favorite shirt, you could wear the other shirt, but this one fits over your head without tugging. WHAT FOODS CONTAIN CARBOHYDRATES?
Let’s review carbohydrates. Why do you need to eat them? What foods contain carbs? List the 3 elements that are contained in carbohydrates. Which of the following is a polysaccharide?
LIPIDS Lipids contain 3 elements; carbon, hydrogen and oxygen.Sounds familiar right!
Fats are triglycerides which are solid at room temperature. Oils are liquid at room temperature. Why are lipids important to our bodies? • Storage of energy. This way if you run low on carbs….. 2. Thermal insulation. 3. Mechanical protection. Example surrounding delicate organs such as the heart. 4. Waterproofing. Like the wax in your ears.
Some fats are called phospholipids. They look like this. Basically , the difference is that instead of 3 fatty acids and one glycerol, they have 2 fatty acids and a glycerol. The also have an end that loves to be in water and a side that repels water. Two layers together is a perfect way to surround a cell or a cell part!
Also, by the way, some hormones are lipids. WHAT CAN YOU EAT TO MAKE SURE YOU HAVE LIPIDS? Butter
Review time. What 3 elements make up the group called lipids? Which of these are a lipid? How can you tell? List 3 ways your body uses lipids. What foods contain lipids?
PROTEINS Proteins are composed of 4 elements: carbon, hydrogen, oxygen and nitrogen. The basic unit is called an amino acid and it looks like this. This is a 3-D image of a protein containing thousands of amino acids connected together & folded to make this distinct shape.
WHY DO YOU NEED TO EAT PROTEINS? Proteins make up most of the structure of your body. Actually, by weight, you are mostly water with proteins in second place. These are muscle cells. This is someone with big muscles. Hair is also made up of protein. Proteins can be enzymes; these proteins regulate chemical reactions in your body. Go go go or Stop stop stop
Review again? Of course!!!! 1. Which of the following suspects is a protein component? 2. List some foods that provide proteins? 3. How does my body use proteins?
NUCLEIC ACIDS Nucleic acids make up DNA and RNA which are gigantic molecules that carry your hereditary information from generation to generation and are used to make proteins (remember them). Nucleic acids are made up of lots of nucleotides (the smallest units) strung together. DNA takes the shape of a double helix. We will learn a lot more about nucleic acids later!!!!
VITAMINS AND MINERALS Micronutrients are nutrients you need in small amounts. (That’s why they’re called micro.) All natural vitamins are organic food substances found only in living things. With few exceptions, our bodies can’t manufacture them. Many enzymes depend on vitamins to work properly. Minerals are inorganic substances such as calcium, iron, and salt that we need for such basic functions as muscles and nerves firing.
WATER makes up more than half the weight of the human body. Without water, humans would die in a few days. All the cell and organ functions depend on water for functioning. It serves as a lubricant and forms the base for saliva and the fluids that surround the joints. It regulates the body temperature, as the cooling & heating are distributed through perspiration. Water helps to alleviate constipation by moving food through in the intestinal tract & thereby eliminate waste. Dehydration is a lack of adequate body fluids for the body to carry on normal body functions. Fluid loss of 5% are considered mild, 10% moderate and up to 15% severe. Severe dehydration can result in cardiovascular collapse and death if not treated quickly. Symptoms: sunken eyes, dry or sticky mucus membranes in the mouth, skin lacks normal elasticity, decreased urination, decreased tears.
Kwashiorkor Meeting energy requirements is basic to survival A diet with excessive nonprotein calories from starch or sugar, but deficient in total protein and essential amino acids, results eventually in kwashiorkor. Kwashiorkor is characterized by generalized edema, "flaky paint' dermatosis, thinning and discolouration of the hair, enlarged fatty liver, and apathy in addition to retarded growth.
Anorexia nervosa is an eating disorder associated with a distorted body image. Inadequate calorie intake results in severe weight loss. Symptoms: Weight loss of 25% or more, cold intolerance, constipation menstruation absent, skeletal muscle atrophy, low blood pressure, dental cavities, increased susceptibility to infection, blotchy or yellow skin, dry hair, hair loss and sometimes death.
Cheese pizza diet causes scurvy in 5-year-old July 17, 2000 NEW YORK (Reuters Health) - When it was discovered that sailors away at sea could stop their gums from bleeding by sucking on a lime, one of the first links between disease--in this case, a vitamin C deficiency--and diet became apparent. But a recent report illustrates that even modern-day children anchored at home are vulnerable to scurvy--a vitamin C deficiency that causes bleeding gums, loose teeth, muscle degeneration and weakness. In one case, a 5-year-old boy ate nothing but Pop-Tarts, cheese pizza, biscuits and water for 5 months, according to a report in the July issue of the Archives of Pediatrics and Adolescent Medicine. He refused fruits, vegetables, juices and vitamins. The result? A case of scurvy--a disease seldom seen in developed countries today.
While the boy was playful, alert and appeared to be growing normally, he developed a limp and was diagnosed with anemia. His gums became swollen and he developed small, purple spots on his skin. Eventually, the pain was so severe he was unable to get out of bed or walk without assistance. After ruling out leukemia or other ailments, the doctors diagnosed the youngster with a severe vitamin C deficiency, most likely caused by his unusual diet. The doctors gave the boy vitamin C, which improved his pain and symptoms within a week.
` TIME FOR THE BIG REVIEW! IDENTIFY EACH OF THE FOLLOWING MACROMOLECULES HOW ARE EACH OF THESE MOLECULES USED IN YOUR BODY? LIPIDS CARBOHYDRATES PROTEINS WHICH ELEMENTS MAKE UP THE CHEMICAL FORMULA OF THE GROUPS LISTED ABOVE?