Endothermic and Exothermic Chemical Reactions Exothermic: Chemical reactions that release energy in...

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Endothermic and Exothermic Chemical Reactions

Exothermic:Chemical reactions that release energy in the

form of heat, light, or sound. Ice pack releases cold

Endothermic:Must absorb energy to function.Cannot occur spontaneously.Leg absorbs cold.

http://chemistry.about.com/cs/generalchemistry/a/aa051903a.htm

http://explore.ecb.org/videos/VLC_file?TYPE=Image&P1=2598&REFERER=OTHER

Kinetic and Potential Energy

http://www.greenscreen.org/articles_sr/EnergyPotentialAndKinetic.htm

• Kinetic energy is greatest during movement

• Potential energy is greatest before movement

Exothermic Vs. Endothermic

Chemical Reactions

Exothermic - Releases energy in the form of light or heat

Endothermic - Absorbs energy from surroundings in the form of heat.

Kinetic Vs. Potential Energy

Kinetic - Gained energy by acceleration or motion.

Potential - Amount of energy based on position.

(Energy is never destroyed but it is restored - Law Conservation of Energy)

Cell RespirationEquation: 6O2+C6H12O6 6CO2+6H2O+Energy

Reactants: Products:6O2+C6H12O6 6CO2+6H2O+Energy

Glucose+ Oxygen Carbon Dioxide +Water+ Energy

http://www.khanacademy.org/video/introduction-to-cellular-respiration?playlist=Biology

Purpose of Celluar Respiration The process that releases energy by breaking down

glucose in the presence of oxygen.• celluar respiration puts the carbon dioxide back into

the atmosphere (which was removed from photosynthesis)

• Takes place in mainly eukaryotes • and some prokaryotes.•Ailson :’)•http://staff.jccc.net/pdecell/cellresp/respintro.html

Cellular respirationPurpose - to break down glucose and other food

molecules in order to get energy. This requires the presence of oxygen.

All cells perform Cellular Respiration. Eukaryotic cells perform respiration in the Mitochondria.

Cellular respiration 6O2+C6H12O6----->6CO2+6H2O+energy

(oxygen + glucose ---> carbon dioxide + water + energy)

•Reactants - C6H12O6 & O2 (glucose and oxygen)

•Products - CO2 & H2O (oxygen and water)

Aerobic and Anaerobic RespirationAerobic

Oxygen required

Cells of the body used: glucose, fatty acids, and amino acids

Glucose and oxygen turn into energy, carbon dioxide, and water

Anaerobic

No oxygen

Produces less energy

GLYCOLYSIS1st part of reactions in cellular respiration - in the cytosol

Breaking down glucose into two pyruvic acid molecules

Released energy used to form ATP and NADH

Consumes and releases ATP, needs the energy to start reaction

http://science.halleyhosting.com/sci/ibbio/cellenergy/resp/respirpics/glycolysis1.gif

Fermentation - when the pyruvate molecules are turned into waste products and no more energy is produced

Lactic Fermentation

- Happens in fungi, bacteria, yogurt and sometimes muscle

- The pyruvate that accumulates as the result of glucose can be converted to lactic acid

Alcoholic Fermentation

- Happens in yeast and bacteria

- Fermentation forms ethyl alcohol and carbon dioxide

By, Ayanna R

ATP: Energy Currency of a Cell

• “ATP” stands for Adenosine triphosphate.• It provides energy to the cell (and the organism!).• The breakdown of glucose, also known as oxidation-

reduction, produces ATP.• The production of ATP looks like this: Adenosine diphosphate + inorganic Phosphate + energy = ATP• ATP works like “rechargeable batteries.”

ATP: Energy Currency of a Cell

• ATP is released when this chemical reaction takes place: ATP produces Adenosine diphosphate + energy + inorganic Phosphate• We get energy from ATP by breaking the bonds between the last

two phosphates in the ATP chain.• Then the cycle starts all over again!

ATP: Energy Currency of a Cell

• “ATP” stands for Adenosine triphosphate.• It provides energy to the cell (and the organism!).• The breakdown of glucose, also known as oxidation-

reduction, produces ATP.• The production of ATP looks like this: Adenosine diphosphate + inorganic Phosphate + energy = ATP• ATP works like “rechargeable batteries.”

Krebs Cycle!!!The Krebs Cycle is

the process that pyruvic acid goes through to be broken down into CO2. As the pyruvic acid enter the mitochondrion of a cell, a removed carbon forms CO2, and removed electrons change NAD+ to NADH. Coenzyme A joins the 2-carbon molecule to form acetyl-CoA. This acetyl-CoAthen adds the 2-carbon acetyl group to a 4-carbon compound, thus forming citric acid.

As the citric acid proceeds through the cycle, it is first broken down into a 5-carbon compound, and then into a 4-carbon compound. Simultaneously, two other CO2 molecules are released, and NAD+ and FAD join with electrons, forming NADH and FADH2.

Krebs Cycle!!!

• Pyruvic acid is broken down into CO2.

• Pyruvic acid enters the mitochondrion of a cell, a removed carbon forms CO2, (forms C-C molecule)

• removed electrons change NAD+ to NADH.

• Coenzyme A joins the 2-carbon molecule to form acetyl-CoA, used to make citric acid.

• Two other CO2 molecules are released, and NAD+ and FAD join with electrons, forming NADH and FADH2.

Electron Transport Chain(ETC)

What?

3rd stage of cellular respiration

When?After the Krebs Cycle

Where?

Mitochondria

http://hyperphysics.phy-astr.gsu.edu/hbase/biology/imgbio/eltranmit.gif

What’s happening?High energy electrons are used to convert ADP to ATP

Part A:

Electrons move down a line of carrier proteins, then form water with excess O and H ions

• Part B:Electrons moving transport H+ ions across the membrane.The inside = + The outside = -

•Part C:H+ ions go through ATP synthases, making them spin.The spinning grabs an ADP and a phosphate, making ATP!

http://fhs-bio-wiki.pbworks.com/f/1259628320/electron_transport_chain.jpg

Electron Transport Chain

The electron transport chain (etc) is what changes ADP to ATP using high energy electrons from the krebs cycle. (The krebs cycle is the series of energy extracting reactions that

breaks down pyruvic acid into CO2.)

How ATP links matter to energy:ATP is adenosine triphosphate (the most basic, but useful energy source of all cells)

ADP is adenosine diphosphate

ATP synthase= protein spheres found in inner membranes of mitochondria

Muscle TissueSkeletal Muscle: Skeletal muscles are muscles attached to bones. They have alternating light and dark bands called striations and many nuclei. They are responsible for voluntary movements.Smooth Muscle: Smooth muscles are found in the walls of the stomach, blood vessels and intestines. Are spindle-shaped, not striated, have one nucleus. Not under voluntary control, responsible for dilating eyes and moving food through digestive tract.Cardiac Muscle: Only found in the heart. Striated, smaller cells, usually have one nucleus but may have two. Non-voluntary.

Skeletal Muscles• The Skeletal Muscles are attached to the bones.• Skeletal Muscles are responsible for specific movements such as typing, dancing, or winking an eye.• Most Skeletal Muscles are controlled by the nervous system.• Skeletal Muscles are large and have many nuclei.

Smooth Muscles Smooth Muscles have one Nucleus.

Found in the walls of hollow structures such as the stomach, broad vessels, and the intestines.

Smooth Muscles move food through the digestive tract and controls the way blood flows through the circulatory system.

Smooth Muscles also decreases the size of the pupils when bright light is being shown onto the eyes.

Connected together by gap junctions.

Cardiac MuscleFound in the heart.

Connected together by gap junctions.

Cardiac muscles flex automatically to squeeze the walls of the heart inward so that the heart beats.

Energy is stored in muscle and tissue in the form of

carbohydrate glycogen. This energy (ATP) can be used physically for a duration of

about 15-20 minutes.

Where is energy stored?

MUSCLE FATIGUE-the decline in ability of a muscle to generate force.

Muscle Fatigue and Work in Antagonistic Pairs

Muscle Fatigue-Muscles capacity to produce max. voluntary action is reduced

Result of the muscle exceeding tissue substrate and oxygenation capacity.Muscle Work in Antagonistic Pairs-

When one muscle contracts, the other relaxes(and vice versa)

Disadvantages and Advantages

H y d r o s k e l e t o n

Fluid Shape: Fits through oddly shaped passages.

Strength: Can pry open by squeezing and expanding. Does not have lifting capacity.

Fragility: Fluid must be incased to work properly.

Healing is fast.

E x o s k e le t o n

Provides bony plate of armor for support and protection of soft internal tissues and organs.

Limits animal size.

Inflexible

Good leverage for the pull of muscles.

During molts animals are extremely vulnerable.

E n d o s k e l e t o n

•Less protective, usually underthe muscle and soft tissue.•Leverage is worse•Can support great size and weight without become too heavy.•Grows fairly smoothly and evenly,no molting

Hydrostatic Skeleton

Lack of permanently rigid structures

No Support

Lack of speed

Exoskeleton

Not much movement

Blood prevents anything that has an exoskeleton from being on their backs to long

Endoskeleton

Can’t mold or shed

Can be hurt by damage and pollution

Exoskeleton

Hydrostatic Skeleton

Endoskeleton

Advantages Hydroskeleton- flexible ,

able to move in tight spaces, and strong muscles, body can change shapes.

Exoskeleton- External skeleton, hard body covering made of chitin,pretty stable muscles, a suit of armor that protects and supports its body

Endoskeleton- calcified plates for animals and bones for humans, protection from plates and bones and harder to be taken down, have irregular and bumpy texture for animals.