Cellular Respiration_Chapter 9

1. What are the redox, oxidation, and reduction reactions?

2. What are the 3 steps of respiration?

3. What is a fermentation?

1. The cell devises the energy stored in food molecules through redox reaction, in which one substance partially or totally shifts electrons to another. The substance receiving electrons is reduced, the substance losing electrons is oxidized. During cellular respiration, glucose is oxidized, and oxygen is reduced to water.

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (as ATP)

2. The three steps are : Glycolysis, The Citric Acid Cycle, and Oxidative Phosphorylation.

3. All cells are able to synthesize ATP via the process of glycolysis. In many cells, if oxygen is not present, pyruvate is metabolized in a process called fermentation. Fermentation complements glycolysis and makes it possible for ATP to be continually produced in the absence of oxygen. By oxidizing the NADH produced in glycolysis, fermentation regenerates NAD+, which can take part in glycolysis once again to produce more ATP.

5 main facts about this chapter.

. With cellular respiration, the energy is released from the chemical bonds into the complex organic molecules.

. Glycolysis splits glucose and produce NADH and ATP, location is cytoplasm.

. Krebs cycle oxidizes pyruvic acid to CO2, produces NADH and FADH2, location is mitochondria matrix.

. Electron Transport Chain converts NADH and FADH2 into ATP, location is mitochondria cristae.

. Electron carrier compounds are the molecules that transport or shuttle electrons within the cell.

Video about cellular respiration :

http://www.youtube.com/watch?v=iXmw3fR8fh0

In this chapter, we learn about cellular respiration, its function, its requirements, and products. We learnt about the redox reaction, the three steps of the respiration, and the fermentation. Glycolysis and the citric acid cycle supply electrons to the electron transport chain, which drives oxidative phosphorylation. Oxidative phosphorylation generates ATP.

Key Terms_ Chapter 1 to 8

Chapter 1 :

biology = ongoing inquiry about the nature of life

evolution = the process of change that has transformed life on Earth from its earliest beginnings to the diversity of organisms living today

reductionism = the reduction of complex systems to simpler components that are more managable to study

cell = organism's basic units of structure and function

system = a simply combination of components that function together

gene = a discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA/RNA (in some viruses)

DNA = deoxyribonucleic acid

genome = the entire "library" of genetic instructions that an organism inherits

inquiry = a search for information and explanation

hypothesis = tentative answer to a well framed question

Chapter 2 :

matter = anything that takes up space and has a mass

element = substance that cannot be broken down to any other substance by any chemical reactions

compound = substance consisting in two or more different elements combined in a fixed ratio

atom = the smallest unit of matter that still retains the properties of an element

dalton = atomic mass unit

atomic number = number of protons, subscript to the left of the symbol

mass number = sum of the protons and neutrons in the nucleus of an atom, superscript to the left of the symbol

energy = capacity to cause change, especially to do work

orbital = 3D space where electron is found 90% of the time

valence = bonding capacity, usually equals to number of unpaired electrons

Chapter 3 :

polar molecule = molecule whose two ends have opposite charges

cohesion = the binding together of like molecules, often by hydrogen bond

adhesion = the clinging of one substance to another

kinetic energy = energy of motion

heat = form of energy

temperature = a measure of heat intensity (average kinetic energy of the molecules)

vaporization (evaporation) = transformation from liquid to gas

heat of vaporization = the quantity of heat a liquid must absorb for 1 g to be converted from the liquid to the gaseous state

solution = a liquid that is completely homogeneous mixture of two or more substances

solvent = dissolving agent of a solution

solute = substance that is dissolved

acid = a substance that increases the hydrogen ion concentration of a solution

base = a substance that reduces the hydrogen ion concentration of a solution

Chapter 4 :

Organic Chemistry = branch of chemistry that specializes in the study of carbon compounds

Vitalism = the belief in a life force outside the jurisdiction of physical and chemical laws

Mechanism = the view that physical and chemical laws govern all natural phenomena, including the process of life

Tetravalence = ability of the molecule to branch off in as many as four directions

Hydrocarbons = Organic molecules made of only carbon and hydrogen

Isomers = Compounds with the same molecular formula but have different structures

Enantiomers = molecules that are mirror images of each other.

Functional groups = A group of atoms attached to a carbon skeleton

ATP = adenosine triphosphate, an important source of energy

ADP = adenosine diphosphate, product of losing one phosphate from ATP

Chapter 5 :

Macromolecules (polymers) = Large molecules formed by joining many subunits together

Polymer = molecule that consists of a single unit (monomer) repeated many times

Monomer = A building block of a polymer

Dehydration/ Condensation synthesis = the chemical reaction that joins monomers into polymers. Covalent bonds are formed by the removal of a water molecule between the monomers

Hydrolisis = Reverse of

condensation synthesis. Breaks polymers into monomers by adding water.

Polypeptide = polymers of amino acids

Proteins = polypeptide chains of Amino Acids linked by peptide bonds

Fatty acid = a long carbon chain (12-18 C) with a -COOH (acid) on one end and a -CH₃ (fat) at the other.

Denaturation = pH shifts, high salt concentrations, heat

Nucleotide = monomer

Chapter 6 :

cell = basic functional unit of all living things

lipid bilayer = double phospholipid membrane --> outer hydrophilic heads and hydrophobic tails pointing towards inside

organelles = bodies within the cytoplasm that serve to physically separate the various metabolic reactions that occur within the cells

nucleus = brain of the cell

ribosome = consisting of RNA

endoplasmic reticulum = stacks of flattened sacs involved in the production of various materials

golgi apparatus = group of flattened sacs arranged like a stack of bowls, functioning to modify and package proteins and lipids into vesicles

lyzosomes = vesicles from a golgi apparatus that contain digestive enzymes

mitochondria = organelles that carry out aerobic respiration

chloroplasts = organelles that carry out photosynthesis

flagella and cilia = structures that protrude from the cell membrane and make wavelike movements

Chapter 7 :

Integral proteins = transmembrane protein with hydrophobic regions that extend into and often completely span the hydrophobic interior of the membrane and with hydrophilic regions in contact with the aqueous solution on either side of the membrane

Peripheral proteins = proteins loosely bounded to the surface of a membrane or to part of an integral protein and not embedded in the lipid bilayer

Glycolipids = molecules formed of membrane carbohydrates covalently bonded to lipids

Glycoproteins = membrane carbohydrates + proteins

Aquaporins = channel proteins (facilitate the passage of water molecules through the membrane)

Diffusion = the movement of molecules of any substance so they spread out evenly into the available space (passive transport)

Osmosis = the diffusion of water

Facilitated diffusion = the spontaneous passage of molecules or ions across a membrane with the assistance of specific transmembrane transport proteins

Passive transport = no energy required / invested

Active transport = energy required

Chapter 8 :

Metabolism = the totality of an organism’s chemical reactions

Energy = the ability to do work

Kinetic energy = energy of motion / action

Potential energy = tored energy or capacity to do work

Energy of activation = Energy needed to convert potential energy into kinetic energy

Entropy = measure of disorder

Free energy = portion of a system’s energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell

Exergonic reaction = release of free energy

Endergonic reaction = absorbs free energy

Energy coupling = a key feature in the way cells manage their energy resources to do work (chemical, transport, mechanical)

Phosphorylated = the recipient of the phosphate group

An Introduction to Metabolism_Chapter 8

1. What are the forms of energy?

2. Explain the structure, function, and the regeneration of ATP.

3. How do enzymes work ?

1. Forms of Energy.

Energy is the capacity to cause change. 3 different energies; kinetic, potential and activation energy. If it is a relative motion of objects; kinetic. ex: moving objects, muscles in the body. there is heat or thermal energy. random movement of atoms and molecules.And object which is not moving has also energy. it has potential energy. this is; because of the objects location and structure. molecules have energy because of the arrangement of atoms.It is a stored energy.The initial investment of energy for starting a reaction is called activation energy. activation energy is often supplied by heat. the energy used to convert the potential energy into kinetic energy.

2. ADENOSINE TRIPHOSPHATE

(ATP). composed by three phosphate groups, one adenine nitrogenous base, and one ribose. (pentose sugar) it is used to build energy but also to make RNA. it is renewable energy source ant they are unstable bonds. ATP works by energizing other molecules by transferring phosphate groups.

Video on ATP :

http://www.youtube.com/watch?v=Lx9GklK0xQg&feature=related

3. Enzymes :

Enzymes speed up metabolic reactions by lowering energy barriers. so lower the activation energy.it would take much more time to solve a substance without the aid of enzymes. enzymes are proteins. it acts as a catalyst.

AB + CD ----> AC + BD

reactants---->products

here is the transition state.

substrate is the material that the enzyme works on. so basically the substance which need to be broken down. active site is the area that the substrate comes in. each substrate has a different and a specific active site that can fix just that substrate. enzymes are affected by the environment, cofactors, coenzymes, inhibitors and by allosteric sites.

5 main facts about this chapter :

. Metabolism is the totality of an organism's chemical processes.

. Catabolic Pathways break down complex molecules into smaller ones, releasing energy.

. Anabolic Pathways consume energy, build complex molecules from smaller ones.

. According to the first law of thermodynamics, energy can be transferred and transformed, but it cannot be created or destroyed.

. Second law of thermodynamics is that energy transfer or transformation increases the entropy of the universe.

In this chapter, we were introduced The Metabolism. We learnt the role of ATP on cell energy, the job of enzymes, and the two main laws of thermodynamic.

Membrane Structure and Function_Chapter 7

1. What is the structure of cell membrane and how are the materials arranged?

2. Why is the cell membrane fluid?

3. What are the differences between passive and active transport?

The structure of cell membrane :

Phospholipids and proteins. There are hydrophilic head and hydrophobic tails. Proteins are outside and inside and phospholipid bilayer is in these protein surface. Proteins are hydrophilic and phosphate bilayer is hydrophobic. There are two protein structure. One is integral, bigger, and the other is peripheral, still connected to the membrane. It also has some cholesterol inside the membrane.

The fluidity of cell membrane.

Phospholipids and proteins move in the membrane freely. The unsaturated hydrocarbon tails of some phospholipids kept the membrane fluid at lower temperature. The cholesterol acts as a temperature buffer. Molecules are not bonded together. It needs to be fluid to function correctly.

Active transport vs Passive Transport.

Active transport, energy used. 3 types; carrier mediated, endocytosis, exocytosis. Passive transport, energy is not used. High concentration to low concentration.. 3 types; diffusion, osmosis, facilitated diffusion.

Videos on active and passive transports :

http://www.youtube.com/watch?v=VUnvwrx8Wq4&feature=related

http://www.youtube.com/watch?v=K7yku3sa4Y8&feature=related

5 main facts about this chapter :

. Carrier mediated transport is against the concentration gradients. (low to high)

. Davson-Danielli model (1935) is also called the sandwich model since it looks like that.

. According to the evidence obtained by use of TEM Microscopes, we know the structure of cell membrane.

. Proteins in cell membrane function differently. Transportation, enzymatic activity, receptor sited for signals, cell adhesion, cell-cell recognition, attachment to the cytoskeleton.

. Integral proteins stick to the membrane by the solubility of their amino acids.

In this chapter, we learnt about the function and structure of cell membrane. Cell membrane is found both in animal and plant cells. It has several functions. It transport materials from outside and inside of the cell. According to the use of energy, the function, structure of the transport change. Cell membrane is fluid because of the unsaturated lipids in the cell membrane. We now know the hydrophilic and hydrophobic parts of the cells and what they contain such as proteins and phospholipids.

The Cell_Chapter 6

1. What is the function and the structure of a cell?

The cell is the basic functional unit of all living things. The cell membrane bounds the cell and encloses the nucleus and cytoplasm. The cytoplasm consists of specialized bodies called organelles suspended in a fluid, called cytosol, which consists %75-90 of water and dissolves substances like proteins and carbohydrates.

2. What is the differences and similarities of prokaryotic and eukaryotic cells?

Eukaryotic organisms include all living things except bacteria and archaea. In eukaryotic cell, DNA is found in the nucleus with a double membrane but in prokaryotic cell the DNA is found in nucleoid, which does not have a membrane. Eukaryotic cells are much bigger than prokaryotic cells. Prokaryotic cells are lacking a true nucleus and the other membrane-closed organelles of the eukaryotic cell.

3. Identify the structures and functions of cell organelles.

. The plasma membrane separates internal events from the external environment and controls the movement of materials into and out of the cell. The plasma membrane is a double phospholipid membrane with the polar hydrophilic heads and the nonpolar hydrophobic tails to the inside of the membrane.

. The nucleus is bounded by the nuclear envelope, a phospholipid bilayer like plasma membrane has. The nucleus contains DNA. Nucleus is the brain of the cell.

. Ribosome makes proteins. They can be free in cytosol or bounded to rough endoplasmic reticulum or nuclear envelope.

. Endoplasmic reticulum is active in membrane synthesis and other synthesis and metabolic process. It has 2 regions, which are rough and smooth. Smooth ER has no ribosome.

. Golgi Apparatus is active in synthesis, modification, sorting and secretion of cell products. They function to modify and package proteins and lipids into vesicles, which move materials between organelles and the plasma membrane.

. Lysosome is the digestive organelle where macromolecules are hydrolyzed. They do not occur in plant cells.

. Periximose produces hydrogen peroxide as a by-product then converts it to water.

. Mitochondrion is the organelle where cellular respiration occurs and most ATP (obtained from carbohydrate) is generated.

. Chloroplast makes the process of photosynthesis. (convertion of energy of sunlight into the chemical energy stored in sugar molecules.) They do not occur in animal cells.

. Cell wall maintains the shape and protects cell from mechanical damage, made of cellulose, polysaccharides and proteins. It is found in plants, fungi, protists and bacteria. They are outside the membrane.

. Vacuole is the large membrane-bounded vesicle in plants. They digest, store, waste disposal, balance water and protect the cell.

Video about the organelles :

http://www.youtube.com/watch?v=T30PvdRJoR4&feature=PlayList&p=A99C8A255510C861&playnext=1&playnext_from=PL&index=11

5 main facts about this chapter :

. The plasma membrane is made of Phospholipids, proteins, cholesterol and glycocalyx.

. In an eukaryotic cell; the genetic information (DNA) is kept in the nucleus but carried out by the ribosomes in the cytosol.

. There are 4 intercellular junctions in animal tissues, and one in plant cells. Plasmodesmata in plant cells, and tight junctions, desmosomes, gap junctions in animal cells.

. To study cells, biologists use microscopes and the tools of biochemistry.

. Mitochondria and chloroplast change energy from one to another.

In this chapter, we learnt about organelles, their structures and functions. We learnt the differences between eukaryotic and prokaryotic cells but also between animal and plant cells. We know there are different kinds of microscopes such as light and electronic microscopy.