Tentative explanation for an observation that requires testing to validate.
Measurement of Nature (Often quantitative).
A logical process that argues from specific instances to a general conclusion (creating a general principle) If my cow eats grass, then yours probably will.
Using a general principle to predict an expected observations.
Hypothesis testing is based on Deductive reasoning. Aka you are trying to detect if something follows what you hypothesised.
Takes the form of if/then statements. (using general principle to predict)
Result expected from a particular test of a hypothesis if the hypothesis were true.
Body of scientifically accepted general principles that explain natural phenomena. A hypothesis that has passed rigorous hypothesis testing and stands the test of time becomes a theory.
Contrived situation designed to test specific hypotheses.
Information collected by scientists during hypothesis testing.
Body of scientifically accepted general principles that explain natural phenomena.
To conclude or come to a conclusion about something due to evidence. Using results from a sample to draw conclusions about the entire population.
What is 'the process of science'?
Making observations of the world, proposing ideas about how something works, testing those ideas, and discarding (or modifying) our ideas in response to the results of a test.
Know the difference between a hypothesis and a prediction. Can hypotheses ever be proven correct? Can they be disproven?
proven- no a hypotheses can not be proven correct, but it can be supported. It can be disproven through an experiment that shows the contrary of a hypothesis.
hypothesis - explanation of how something works
prediction - is the result you would expect if the hypothesis were true.
What is a controlled experiment?
A controlled experiment is one that contains a control group, meaning that for an experiment a subject receives no treatment (or a placebo). Control groups are designed to eliminate as many alternative hypotheses as possible for the results of the experiment.
Placebos are fake treatments in an experiment. They are used to determine whether the treatment that claims to be having an effect is really doing anything compared to the placebo - this is to eliminate the cures that are "in people's heads".
A blind experiment is a test in which subjects are not aware of exactly what they are predicted to experience.
A double Blind
A double-blind experiment is an experimental design protocol when both research subjects and scientists performing the measurements are unaware of either the experimental hypothesis or who is in the control or experimental group.
What is a correlation? Does it prove cause-and-effect?
A correlation is a relationship between two variables. Correlation does not signify causation because normally a correlation cannot eliminate all alternative hypotheses.
What is the difference between primary, secondary, and anecdotal sources of information? What role does peer review play in the process of scientific publications?
Primary is information from a direct source and is therefore regarded as more accurate. A secondary source is a spin off of a primary source, and usually has less technical terms.
Anecdotal sources is when the advice is based on one individual's personal experience.
Peer review provides a way to weed out false information. If someone knows the material of a paper, they can make corrections before it is published. Articles in
peer reviewed journals are a primary source.
What did we learn from our class demonstration regarding gingko biloba, chocolate bars, and learning? (Did gingko help short term memory performance? chocolate? What did the Scientific American paper say about it?)
In the end only a few students reported that they did better after taking gingko biloba.
No one ate chocolate..... it was sugar pills....
The Scientific American paper came to the conclusion that there was not much difference between the placebo/control group and those that received the Ginko. There was some improvement in short-term memory in young adults, but not enough to conclude positive effects of the Ginko.
What evidence came from the Mars meteorite that suggested there may have been life on Mars? What evidence was NOT on the meteor that would have further strengthened that conclusion?
Appeared to contain the same features that scientists use to demonstrate the existence of life in 3.6-billion-year-old Earth rocks - there were fossils, various minerals that are characteristic of life, and evidence of complex chemicals typically produced by living organisms (carbon).
It lacked convincing evidence of macromolecules - organic molecules that are known to be produced only by living organisms.
All of the physical and chemical reactions that produce and use energy, the synthesis of substances necessary for life, and the excretion of wastes generated by these processes and the breaking down of substances.
he steady state condition an organism works to maintain. (Internal constancy)
The substance that is dissolved in a solution
A substance, such as water, that a solute is dissolved in to make a solution.
Any starting material in a chemical reaction.
The modified chemical that results from a chemical or enzymatic reaction.
A positively charged subatomic particle
a subatomic particle that has no charge and that is found in the nucleus of an atom
A negatively charged subatomic particle.
A substance that cannot be broken down into any other substance.
Combined number of protons and neutrons in an atom
Describes a molecule with regions having different charges; capable of ionizing (positive and negative ends - water).
Non Polar Molecule
atoms of a molecule carry no partial charge. Won't dissolve in water. Hydrophobic. (i.e. oil)
What 9 things must something have in order to be living?
4. Response to external environmental stimuli
6. Contain a common set of biological molecules k(carbohydrates, proteins, lipids, DNA)
7. Are composed of cells
8. Can maintain homeostasis
9. Can evolve - can change in response to the environment overtime
Remember: Good men can have red socks made by elves
Growth, Movement, Cells, Homeostasis, Reproduction, Stimuli, Metabolism, Biological molecules, Evolve
Why is water so important to life? What role does hydrogen bonding play in the formation of water? What is 'cohesion' and why is it important to living systems as a property of water?
Without it everything would die.
Hydrogen Bond - A type of weak chemical bond in which a hydrogen atom of one molecule is attracted to an electronegative atom of another molecule.
Cohesion - The tendency for molecules of the same material to stick together... Cohesion is much stronger in water than in most liquids as a result of hydrogen bonding and is an important property of many biological systems. i.e. plants, to help transport column of water from roots to the leaves.
A type of weak chemical bond in which a hydrogen atom of one molecule is attracted to an electronegative atom of another molecule.
The tendency for molecules of the same material to stick together... Cohesion is much stronger in water than in most liquids as a result of hydrogen bonding and is an important property of many biological systems. i.e. plants, to help transport column of water from roots to the leaves.
(water fearing) A substance which water is NOT attracted to. (ie. oil)
(water loving) Water is attracted to these substances. (dissolves in water, ie. sugar)
pH less than 7. A substance that increases the concentration of hydrogen ions in a solution.
pH greater than 7. A substance that decreases the concentration of hydrogen ions in a solution.
refers to how acidic or basic a substance is. (p = negative log. H = concentration of hydrogen. Thus, pH = -log[H] )
What is organic chemistry?
The chemistry of carbon-containing substances.
Why is carbon such an important molecule for living organisms?
Life on earth is based on the chemistry of Carbon, which can make bonds with up to four other elements.
Your reading covered chemical bonding which includes both ionic and covalent bonds. What's the difference between these two?
Ionic Bond - A chemical bond resulting from the attraction of oppositely charged ions.
Form between positively and negatively charged ions. Tend to be weak bonds. Transfer of electrons (one gains an electron, while the other loses it).
Covalent Bond - A type of strong chemical bond in which two atoms share electrons.
A chemical bond resulting from the attraction of oppositely charged ions.
Form between positively and negatively charged ions. Tend to be weak bonds. Transfer of electrons (one gains an electron, while the other loses it).
A type of strong chemical bond in which two atoms share electrons.
small. (ie. vitamins and minerals) Only needed in small amounts.
Any of the large molecules including polysaccharides, proteins, and nucleic acids, composed of subunits joined by dehydration synthesis... organic molecules known to be produced only by living organisms. A large amount is required for life for energy and maintenance. Acquired from the food we eat.
(Carbohydrates, Proteins, Lipids, Nucleic Acids)
What are the building block molecules of a carbohydrate
Carbohydrate - Carbon, Hydrogen, Oxygen.
What are the building blocks of a Protein?
Composed of amino acid monomers arranged in different orders
What are the Building blocks of a Fat?
Glycerol and three fatty acids
What is a polysaccharide?
A carbohydrate composed of three or more monosaccharides. (cellulose)
simple sugar (glucose, fructose)
A double sugar consisting of two monosaccharides joined together by a glycosidic linkage. (table sugar, sucrose, lactose)
What role do proteins play in living systems? What are they made of and what holds them together?
Proteins play structural, enzymatic, and transport roles in cells. They are composed of amino acid monomers arranged in different orders held together by peptide bonds.
What are lipids?
partially or entirely hydrophobic organic molecules made primarily of hydrocarbons, including fats, steroids, and phospholipids.
Briefly define a fat
Energy-rich, hydrophobic lipid molecule composed of a three-carbon glycerol skeleton bonded to three fatty acids. Can be burned to produce energy. Also used as energy storage in living organisms.
Briefly define a steroid
naturally occurring or synthetic organic fat-soluble substance that produces physiological effects. Helps maintain the fluidity of membranes (cholesterol).
One of three types of lipids, components of cell membranes. Important constituents of the membranes that surround cells and that designate compartments within cells.
What is DNA comprised of?
1. "Backbones" made of sugars and phosphates. 2. "Rungs" made of nitrogenous bases.
What are the 4 nitrogenous bases in DNA? How do they bond to one another?
4 bases - Adenine, guanine, thymine, cytosine. A-to-T base pairs have 2 hydrogen bonds holding them together. C-to-G pairs have 3 hydrogen bonds holding them together.
Type of cell that does not have a nucleus or membrane-bound organelles.
Cell that has a nucleus and membrane-bound organelles.
Be able to briefly describe the function and location of Plasma Membrane
Composed of a bilayer of phospholipds perforated by proteins Proteins in the bilayer help transport substance across the hydrophobic core of the membrane. Cholesterol in the membranes of animal cells helps maintain the fluidity of the membrane.
Be able to briefly describe the function and location of Nucleus
Spherical structure surrounded by two membranes, together called the nuclear envelope. The nuclear envelope is studded with nuclear pores that regulate traffic into and out of the nucleus. Inside the nucleus is chromatin, composed of DNA and proteins. The nucleolus is where ribosomes are produced.
Be able to briefly describe the function and location of Mitochandria
Plant and animal cells contain mitochondria, energy-producing organelles surrounded by two membranes. The inner and outer mitochondrial membranes are separated by the intermembrane space. The highly convoluted inner membrane carries many of the proteins involved in producing ATP. The matrix of the mitochondrion is the location of many of the reactions of cellular respiration.
Be able to briefly describe the function and location of Chloraplast
Important organelle present in plant cells, uses the sun's energy to convert carbon dioxide and water into sugars. Each chloroplast has an outer membrane, an inner membrane, a liquid interior called the stroma, and a network of membranous sacs called thylakoids that stack on one another to form structures called grana. Chloroplasts also contain pigment molecules that give green parts of plants their color.
Be able to briefly describe the function and location of Ribosomes
Found in eukaryotic and prokaryotic cells. Built in the nucleolus and shipped out of the nucleus through nuclear pores to the cytoplasm, where they are used as workbenches for protein synthesis. They can be found floating in the cytoplasm or tethered to the ER (endoplasmic reticulum).
Be able to briefly describe the function and location of Golgi Apparatus
Stack of membranous sacs. Vesicles from the ER fuse with it and empty their protein contents. The proteins are then modified, sorted, and sent to the correct destination in new transport vesicles that bud off from the sacs.
Be able to briefly describe the function and location of Lysosome
membrane-enclosed sac of digestive enzymes that degrade proteins, carbohydrates, and fats. Lysosomes roam around the cell and engulf targeted molecules and organelles for recycling.
Be able to briefly describe the function and location of Centriole
Barrel-shaped rings composed of microtubules that help move chromosomes around when a cell divides. Involved in microtubule formation during cell division and the formation of cilia and flagella.
What makes a plant cell different than an animal cell?
Plant cells contain chloroplast and central vacuoles, but Animal cells don´t. Animal cells don't have a cell wall, but plant cells do.
Plant cells perform photosynthesis, animal cells do not. (but both go through cellular respiration)
Describe the structure of the plasma membrane.
Internal and external cell membranes are composed in part of phospholipids. When phospholipid molecules are placed in a watery solution, such as in a cell, they orient themselves so that their hydrophilic heads are exposed to the water and their hydrophobic tails are away. They cluster into a form called a phospholipid bilayer.
What does the 'tree of life' refer to when we are discussing evolutionary theory?
All organisms diverge from a common ancestor. Then they split because of natural selection into two groups of prokaryotes and one group of eukaryotes. Eukaryotes are further grouped into several categories. (Mostly single-celled organisms like algae and three major multicellular groups - plants, fungi, and animals)
What are examples of micro- and macronutrients?
micronutrients - nutrient needed in small quantities. (vitamins, minerals)
macronutrients - nutrient needed in large quantities. (water, carbohydrates, proteins, and fats)
Be able to briefly describe the role in nutrition of water
helps the body disperse other nutrients, helps dissolve and eliminate waste products of digestion, helps maintain blood pressure, is involved In virtually all cellular activities, regulates body temperature.
Be able to briefly describe the role in nutrition of carbohydrates
the major source of energy for cells. Energy is stored in the chemical bonds between the carbons, hydrogens, and oxygens that comprise carbohydrate molecules. Can exist as single-unit monomers or can be bonded together to produce longer-chain polysaccharide polymers. Body digests complex carbohydrates more slowly than simple because there are more bonds to break. (fruits, vegetables, grains)
Be able to briefly describe the role in nutrition of proteins
beef, poultry, fish, beans, eggs, nuts, dairy. Composed of amino acids. Help in important cellular functions.
Be able to briefly describe the role in nutrition of fat
source of energy. Twice as much energy as carbs or proteins. Energy is stored in the carbon, oxygen, ad hydrogen bonds of fat molecule. (meat, milk, cheese, vegetable, oils, nuts). Body can synthesize most of the fatty acids it requires.
What is a complex carbohydrate? cholesterol?
carbohydrate consisting of 2 or more monosaccharides.
cholesterol - a steroid found in animal cell membranes that affects membrane fluidity. Serves as the precursor to estrogen and testosterone.
What is the difference between HDL and LDL cholesterol?
HDL - high-density lipoproteins. Contain more protein than cholesterol. Scavenge excess cholesterol and return it to the liver to make bile.
LDL - low-density lipoproteins. High proportion of cholesterol and are low in protein. Distribute cholesterol synthesized by the liver and cholesterol derived by dirt throughout the body. Important for carrying cholesterol to cells, where it's used to make plasma membranes and hormones.
What is an essential amino acid? essential fatty acid?
essential amino acid - any of the amino acids that humans cannot synthesize and thus must be obtained by the diet.
essential fatty acids - any of the fatty acids that animals cannot synthesize and must be obtained by the diet.
How do saturated fats differ from unsaturated fats? What are examples of each?
Saturated fats are typically found in animals. Unsaturated are typically found in plants. Saturated fats are carbons bound to hydrogen in single bonds and solid at room temperature. They are found in butter and other fats. Unsaturated fats containing carbon to carbon double bonds and is liquid at room temperature. Found in vegetable oil.
What is hydrogenation and why was this done to fats? What is the downside of hydrogenated fats?
Hydrogenation is a process in which food manufacturers add hydrogen atoms to unsaturated fats by combining hydrogen gas with vegetable oils under pressure. It increases the fat's level of saturation, slows spoilage and solidifies liquid oils making food less greasy and extending their shelf life. An example is margarine. Hydrogenation creates trans fats which are harder for the body to break down and solidify liquid fats. Trans fats are common in fast foods and include the risk of clogged arteries, heart disease and diabetes.
What is a vitamin and what does it do for your body? a mineral? examples of each?
A vitamin is a micronutrient that is made up of organic substances, most of which the body can't make. They speed up the bodies chemical reactions. They also help speed up the absorption of other nutrients. Some may help prevent cancer and heart disease and slow the aging process. An example is thiamin found in pork, whole grains, leafy greens and vegetables. A mineral is a substance that are essential for many cell functions. Minerals are inorganic (don't contain carbon). Important for proper fluid balance, muscle concentration and building bones and teeth. Example is calcium found in cheese, milk, and dark green veggies.
Why the concern over processed versus whole foods? What do whole foods have that processed foods do not?
Processed foods are stripped of much of their nutritive value
Whole foods have nutrients like vitamins and minerals
Many whole foods also have antioxidants, which are thought to play a role in the prevention of many diseases, including cancer.
What is an Enzyme?
Protein used to break down ingested foods and liberate energy stored in chemical bonds.
A substance that enhances the action of an enzyme
Energy required to start metabolic reaction (serves as barrier to catalysts
Substrate induces the enzyme to change shape and conform to contours of the substrate
What is a calorie? what influences the number of calories your body burns while engaged in various activities?
Amount of energy required to raise temperature of 1 gram of water by 1 degree Celsius.
Number of calories burned depends on things like the amount of exercise, gender, genes,
What are we referring to when we speak of a person's basal metabolic rate?
Amount of energy used while resting.
What is the difference between passive transport and active transport in cells? What are examples of passive transport we discussed? Which method consumes energy in the process? what supplies that energy?
Passive transport - the diffusion of substances across a membrane with their concentration gradient and not requiring an input of ATP. (diffusion, facilitated diffusion, osmosis)
active transport - the ATP-requiring movement of substances across a membrane against their concentration gradient.
Glucose supplies energy in ATP.
How do exocytosis and endocytosis vary?
Exocytosis is the movement of substances out of the cell and Endocystosis is the movement of substsances into the cell.
What is the BMI? what is a healthy BMI range for men and women? Why is this an imperfect measure of an ideal body fat % for all people?
It is a chart based on weight and height that calculates a value that correlates with body fat and risk of illness.
20-24.9 is considered healthy
This is imperfect because it does not discern between muscle mass and body fat, in other words it is based off averages and not you personally.
What is obesity? which diseases are associated with it?
Obesity is the condition of having a BMI of 30 or greater.
The diseases associated are diabetes, hypertension, heart attack, stroke, and joint problems
What are anorexia and bulimia? What diseases are associated with these ailments?
Anorexia is self starvation and bulimia is binge eating followed by purging.
Anorexia can starve heart muscles to the point that altered rhythms develop. Blood flow is reduced and blood pressure drops. And weakened bones can develop causing OSTEOPOROSIS!!!!
What is global warming, global climate change, and the greenhouse effect?
Global warming= increases in average temperature as a result of the release of increased amounts of carbon dioxide and other greenhouse gases into the atmosphere
global climate change= Just a different way of saying Global Warming
greenhouse effect= the retention of heat in the atmosphere by carbon dioxide and other greenhouse gases
What are the 'greenhouse' gases?
Atmospheric gasses: methane, nitrous oxide, water vapor, and (most importantly) carbon dioxide; that block back heat radiated from the earth back onto the earth.
Define heat and temperature.
Heat- the total amount of energy associated with the movement of atoms and molecules in a substance.
Temperature- measure of the intensity of heat or kinetic energy (energy of movement).
How is carbon dioxide cycled through living and non-living systems?
Carbon cycles between living organisms, the atmosphere, bodies of water, and the soil.
Define cellular respiration.
Cellular respiration- metabolic reactions occurring in cells that result in the oxidation of macromolecules to produce ATP. Performed in the mitochondria.
What are examples of fossil fuels?
-Oil, natural gas, coal
What evidence is cited by the text for an anthropogenic (human origin) cause behind global warming?
Industry, followed by transportation, then by commercial, residential, and agricultural emissions.
What is cellular respiration? What are the raw materials in and products out associated with cellular respiration?
Cellular respiration - metabolic reactions occurring in the cells that result in the oxidation of macromolecules to produce ATP.
C6H12O6 (glucose) + 6O2 (oxygen) = 6CO2 (carbon dioxide) + 6H2O (water) + ATP. (you don't need to know the chemical equations, just what goes in and what goes out)
What is ATP? ADP? what role does phosphorylation play in creating ATP from ADP?
ATP - adenosine triphosphate. Supplies energy to cells because it stores energy obtained from the movement of electrons that originated in food into its own bonds.
ADP - breaking the terminal phosphate bond of ATP releases energy that can be used to perform cellular work and produces ADP plus a phosphate. (when ATP loses a phosphate)
Phosphorylation - ATP can energize other compounds through this. ATP transfers a phosphate to another molecule.
What three types of cellular work are powered by ATP molecules?
1. mechanical work- breaking things apart
2. transport work- bringing glucose molecules in
3. chemical work- making bonds
What is glycolysis? The Krebs Cycle? Where do each take place?
glycolysis - (occurs in the cytoplasm of the mitochondria) The splitting of glucose into pyruvate which helps drive the synthesis of a small amount of ATP.
The krebs cycle - (inside second membrane) produces CO2 and ATP. Breaks down glucose.
What link is there between global warming and cellular respiration?
Enzymes work best at a certain temperature so the higher the temperature the more they are agitated and they speed up.
What is photosynthesis? What role does the chloroplast play in photosynthesis?
Photosynthesis - process by which plants, along with algae and some bacteria, transform light energy to chemical energy.
Chloroplast - absorbs sunlight and uses energy derived to produce sugars.
The inputs and outputs of Photosynthesis are:
Carbon dioxide + Water + light energy = Glucose + Oxygen
Be able to define the stroma, thylakoids, and grana.
Stroma- The semi-fluid matrix inside a chloroplast where the Calvin cycle of photosynthesis occurs.
Thylakoids- Flattened membranous sac located in the chloroplast stroma. Function in photosynthesis.
Grana- Stacks of thylakoids in the chloroplast.
What is the Calvin Cycle?
A series of reactions that occur in the stroma of plants during photosynthesis that utilize NADPH and ATP to reduce carbon dioxide and produce sugars. Builds up glucose.
Receives ATP, NADPH from the light reaction and CO2 from outside and creates Sugar and Oxygen.
How does deforestation effect global warming?
-Less trees to convert CO2 in the atmosphere back to O2.
What are some ways in which you can help slow global warming?
Ride a bike instead of drive.
Plant more trees.