By: Migdy Diaz
Per.3 Introduction
Explain why you are already a scientist.
Since the day of our birth I believe we are all born a scientist. We are always trying to figure things out and discover a deeper meaning. We are born curious and I in particular am a very curious person. I always want to find out the “why” of things, many times just ending in more “whys”. I love to explore and that’s why I believe I am already a scientist.
Describe career goal.
My career goal is to become an astronomer. I have always been fascinated with the stars and galaxies, and want to find out how it all works. As an astronomer I want to discover a new way of living outside our planet. Hopefully working in NASA and with a team this will be possible in the near future.
Personal view towards education.
I see education as the most important thing essential to life. Without education we are nothing. Education makes us who we are, it is all around us and constantly it is being transmitted into us. There is never a moment when we know everything, there is always something new to learn.
Describe what keeps you motivated in life.
What keeps me motivated in life is love. I always feel love all around me, from my friends to my family, there is almost never a moment I feel down in life. They are always there for me, and I hopefully will always be there for them. Unit 1
Chapter 1 Themes In The Study Of Life
Briefly describe unifying themes that pervade the science of biology.
Unifying themes that pervade in the science of biology include the structural level by which life is organized, cell and their structure and function, study of life and heritable information such as that of DNA and organisms and their interaction with their environment.
Diagram the hierarchy of structural levels in biology.
Figure 0110
Explain how the properties of life emerge from complex organization.
The properties of life emerge from complex organization. Firstly, atoms are ordered into complex biological molecules. These molecules of life are then arranged into structures called organelles, which are the components of cells. Although some organisms consist of single cells, multi-cellular organisms have its similar cells grouped into tissues and the specific arrangement of tissues form organs. It is through this hierarchy that all biological processes transcend and life emerges.
Describe seven emergent properties associated with life.
• Order. Organisms are highly ordered, and other characteristics of life emerge from this complex organization. • Reproduction. Organisms reproduce; life comes only from life (biogenesis). • Growth and Development. Heritable programs stored in DNA direct the species-specific pattern of growth and development. • Energy Utilization. Organisms take in and transform energy to do work, including the maintenance of their ordered state. • Response to Environment. Organisms respond to stimuli from their environment. • Homeostasis. Organisms regulate their internal environment to maintain a steady-state, even in the face of a fluctuating external environment. • Evolutionary Adaptation. Life evolves in response to interactions between organisms and their environment. Explain how technological breakthroughs contributed to the formulation of the cell theory and our current knowledge of the cell.
Technological breakthroughs have aided in the formulation of the cell theory and our current knowledge of the cell. A powerful instrument called the electron microscope has been able to expose the complex structure of cells. This instrument proved an improvement to the discoveries of the English scientist, Robert Hooke, and his contemporary, Anton van Leeuwenhoek. The electron microscope showed that all cells are enclosed by a membrane that regulates the passage of materials between the cell and its surroundings and that every cell, at some point in its life span, contains DNA.
Distinguish between prokaryotic and eukaryotic cells.
Prokaryotic- The DNA is not separated from the rest of the cell into a nucleus. They also lack the cytoplasmic organelles typical of eukaryotic cells. Almost all prokaryotic cells have tough external cell walls.
Eukaryotic- By far are more complex, is subdivided by internal membranes into many different functional compartments, or organelles. The DNA is organized along with proteins into structures called chromosomes contained within a nucleus, the largest organelle of most cells.
Explain, in their own words, what is meant by "form fits function."
Depending what the object is possible of is what it can achieve. As in, a bird’s build makes flight possible. The correlation between structure and function can apply to the shape of an entire organism.
List the five kingdoms of life and distinguish among them.
*KINGDOM MONERA - where all prokaryotes are palced in; *KINGDOM PROSTISTA - consists of unicellular eukaryotes and their relatively simple multicellular relatives; *KINGDOM PLANTEA - consists of multicellular eukaryotes that carry out photosynthesis, ei. tullips; *KINGDOM FUNGI - the nutritional mode of its members, organisms that absorbnutrients after decomposing organic refuse, ei. costa rica cup fungi; *KINGDOM ANIMALIA - consists of multicellular eukaryotesthat ingest other organisms.ei. rose pellicans
Figure 0110 Outline the scientific method.
A. Question B. Hypothesis C. Experimental Design D. Collecting data E. Analyze data F. Interpretation G. Write it up
Distinguish between inductive and deductive reasoning.
Induction is reasoning set from a set of specific observations to reach a general conclusion; it is when you make an inference from a set of specific observations to reach a general conclusion. While Deductive reasoning is the opposite (general to specific), it involves predicting experimental results that are expected if the hypothesis is true.
Explain how science and technology are interdependent.
Technology, especially in the form of new instruments, extends our ability to observe and measure and enables scientists to work on questions that were previously unapproachable. In turn, technological inventions often apply the discoveries of science. For example, the inventors of the electron microscope borrowed electromagnetic theory from physics. Chapter 2 The Chemical Context Of Life
Define element and compound.
Element- Any substance that cannot be broken down to any other substance.
Compound- A chemical combination, in a fixed ratio, or two or more elements.
State four elements essential to life that make up 96% of living matter.
Carbon, Oxygen, Hydrogen, and Nitrogen
Describe the structure of an atom
Neutrons, Protons, and electrons. Neutrons and protons are packed together tightly to form a dense core, or nucleus, at the center of the atom. The electrons move about this nucleus at nearly the speed of light
Define and distinguish among atomic number, mass number, atomic weight, and valence.
Atomic Number- number of protons in the nuclei
Mass Number- the sum of protons plus neutrons in the nucleus of an atom
Atomic Weight- The total atomic mass, or mass number
Valence- Bonding capacity Given the atomic number and mass number of an atom, determine the number of neutrons.
Subtract the atomic number from the mass number, and this would equal the number of neutrons.
Explain the octet rule and predict how many bonds an atom might form.
The Octet Rule is: A valence shell is complete when it contains eight electrons. Except: H and He. It does not form any bonds because it already has eight electrons and doesn’t need to borrow from another atom.
Define electronegativity and explain how it influences the formation of chemical bonds.
Electronegativity is an atom’s ability to attract and hold electrons. The more electronegative an atom, the more strongly it attracts shared electrons. The difference in electronegativity between interacting atoms determines if electrons are shared equally, shared unequally, gained or lost. Nonpolar covalent and ionic bonds are two extremes of a continuum from interacting atoms with similar electronegativities to interacting atoms with very different electronegativities.
Distinguish among nonpolar covalent, polar covalent and ionic bonds.
Nonpolar covalent- electrons are shared equally Polar covalent- If one atom is more electronegative than the other, electrons are share equally Ionic bonds-attraction between cations and anions
Describe the formation of a hydrogen bond and explain how it differs from a covalent or ionic bond.
Hydrogen bond is formed by the charge attraction when a hydrogen atom covalently bonded to one electronegative atom is attracted to another electronegative atom. It’s weak attractive force is about 20 times easier to break than a covalent bond. It is a charge attraction between oppositely charged portions of polar molecules. It can also occur between hydrogen that has a slight positive charge when covalently bonded to an atom with high electronegativity. Themes
1. Science as a process- The structure of an atom, moving on to the process undertaken to essentially determine the number of subatomic particles in each atom 2. Evolution- "Chemical reactions and physical processes on the early Earth created an environment that made life possible. And life, once it began, transformed the planet's chemistry," stated Chapter 2 (pp 38) Chemical evolution on the early Earth made the origin of life possible. 3. Relationship of Structure to Function- The number of bonds the atom will form by the number of electrons required to complete that the number of bonds the atom’s valence shell. 4. Science, Technology, and Society- Biology, Microscope, Educated
5. Regulation- protons and electrons regulate each other so that the atom can stay neutral Chapter 3 Water And The Fitness Of The Environment
Describe how water contributes to the fitness of the environment to support life.
All organisms familiar to us are made mostly of water and life in a world where water dominates climate and, many other features of the environment. Most cells are surrendered by water, and cells contain from 70% to 95% water.
Describe the structure and geometry of a water molecule, and explain what properties emerges as a result of this structure.
Water is an excellent solvent (The dissolving agent of a solution. Water is most solvent known). Water has a high heat capacity (The degree to which substance changes temperature in response to a gain or loss of heat). Water has a strong cohesion (The attraction between like substances), and high surface tension (A measure of how difficult it is to stretch or break the surface of a liquid). Water adheres (The attraction of unlike substance) to other molecules.
Explain the relationship between the polar nature of water and its ability to form hydrogen bonds.
Hydrogen bonds are weak bonds between molecules. They form when a positively charged hydrogen atom in one covalently bonded molecules is attracted to a negatively charged area of another covalently bonded molecule. In water, the positive pole around a hydrogen atom forms a hydrogen bond to the negative pole around the oxygen atom of another water molecule.
List five characteristics of water that are emergent properties resulting from hydrogen bonding.
1.Solvent 2.Heat capacity 3.Cohesion 4.Surface tension 5.Adhesion Describe the biological significance of the cohesiveness of water.
Cohesion due to hydrogen bonding contributes to the transport of water against gravity in plants.
Explain how water's high specific heat, high heat of vaporization and expansion upon freezing affect both aquatic and terrestrial ecosystems. N/A
Explain how the polarity of the water molecule makes it a versatile solvent.
Water is an unusually versatile solvent because its polarity attracts it to charged polar substances.
Write the equation for the dissociation of water, and explain what is actually transferred from one molecule to another.
H2O = H+ + OH-
Explain the basis for the pH scale.
The pH scale compresses the range of H+ an OH- concentrations by employing a common mathematical device: logarithms
Themes
1. Science as a process- The dissociation of water
2. Evolution- Waters hydrogen bonding
3. Relationship of Structure to Function- Surface tension allowing “walking on
water”
4. Interdependence in Nature- Humans are made up of 70% to 95% of water
5. Science, Technology, and Society- Chemistry, pH scale, Acid Chapter 4 Carbon And The Molecular Diversity Of Life
Explain how carbon’s electron configuration determines the kinds and number of bonds carbon will form.
Carbon has a total of six electrons, with two in the first electron shell and four in the second shell. Having four valence electrons in a shell that holds eight, carbon has little tendency to gain or lose electrons and form ionic bonds; it would have to donate or accept four electrons to do so. Instead, a carbon atom completes its valence shell by sharing electrons with other atoms in four covalent bonds. Each carbon atom thus acts as an intersection point from which a molecule can branch off in up to four directions. This to travel is one factor of carbon’s versatility that makes large, complex molecules possible.
Describe how carbon skeletons may vary, and explain how this variation contributes to the diversity and complexity of organic molecules.
The skeleton varies in length and may be straight, branched, or arrange in closed rings. Some carbon skeletons have double bonds, which vary in number and location. Such variation in carbon skeletons is one important source of the molecular complexity and diversity that characterize living matter. In addition, atoms of other elements can be bonded to the skeletons at available sites.
Recognize the major functional groups, and describe the chemical properties of organic molecules in which they occur.
1.Hydroxly Group (-OH) 2.Carbonyly Group (=CO) 3.Carboxyl Group (-COOH) 4.Amino Group (-NH2) 5.Sulfhydryl Group (-SH) 6.Phosphate Group (H3PO4) Themes
1. Science as a process- The balance of chemicals
2. Evolution- How things are not destroyed, but just rearranged
3. Relationship of Structure to Function- Carbons is very versatile
4. Interdependence in Nature- Nothing can be destroyed or made up
5. Science, Technology, Society- Organic Chemistry, Atom, People Chapter 5 The Structure And Function Of Macromolecules
List the four major classes of biomolecules.
Carbohydrates, Lipids, Proteins, and Nucleic acid.
Describe how covalent linkages are formed and broken in organic polymers.
N/A
Describe the distinguishing characteristics of carbohydrates, and explain how they are classified.
Carbohydrates include sugars and their polymers. *monosaccharide- they generally have molecular formulas that are some multiple of CH2O. *disaccharide- double sugars, consists of two monosaccharides joined by a glycosidic linkage, a covalent bond formed between two monosaccharides. *polysaccharides- they are polymers in which a few hundreds to a few thousands monosaccharide are linked together.
Identify a glycosidic linkage and describe how it is formed.
A covalent bond formed between two monosaccharide. For instance, maltose is a disaccharide formed by linking two molecules of glucose.
Describe the important biological functions of polysaccharides.
Some polysaccharides are storage material, hydrolyzed as needed to provide sugar for cells. Other polysaccharides serve as building material for structures protecting the cell or the whole organism.
Explain what distinguishes lipids from other major classes of macromolecules.
What distinguishes lipids is that they have little or no affinity to water. The hydrophobic behavior of lipids is based on their molecular structure. Although they may have some polar bonds associated with oxygen, lipids consist mostly of hydrocarbon. Families of lipids are fats, phospholipids, and steroids.
Describe the unique properties, building block molecules and biological importance of the three important groups of lipids: fats, phospholipids and steroids.
Fats- are large molecules, but they are not polymers. A fat is constructed from two kinds of smaller molecules which are glycerol and fatty acids. Phospholipids- are structurally related to fats, but they have only two fatty acids rathere than three. Steroids-are lipids characterized by a carbon backbone consisting of four interconnected rings.
Distinguish between a saturated and unsaturated fat
Saturated fat have a maximum number of hydrogen atoms and unsaturated have one or more double bonds between their carbons.
Describe the characteristics that distinguish proteins from the other major classes of macromolecules, and explain the biologically important functions of this group.
Proteins account for more than 50% of the dry weight of most cells, and they are used for structural support, storage, transport of other substances, signaling from one part of the organism to another, movement, and defense against foreign substances.
List and recognize four major components of an amino acid
Hydrogen atom, carboxyl group, amino group, and asymmetric carbon
Explain what determines protein conformation
Protein has a complex architecture. We can recognize three superimposed levels of structure known as primary, secondary, and tertiary structure. There is also a fourth level called quaternary structure which occurs when a protein consists of two or more polypeptide chains.
Define primary structure
Primary structure is the unique sequence of amino acids. Describe the two types of secondary protein structure
The secondary structure is the folding or coiling of polypeptide into repeating configuration. The alpha helix which is a delicate coil held together by hydrogen bonding between every fourth peptide bond, and the pleated sheet, in which the polypeptide chain folds back and fourth, or where two regions of the chain lie parallel to each other.
Explain how weak interactions and disulfide bridges contribute to tertiary protein structure.
The hydrophobic interaction contributes by as a polypeptide folds into its functional conformation, amino acids with nonpolar side chains usually congregate at the core of the protein out of contact with water. The disulfide bridges form strong covalent bonds.
Describe quaternary protein structure.
Quaternary structure is the overall protein structure that results from the aggregation of these polypeptide subunits.
Define denaturation and explain how proteins may be denatured.
Denaturation is a process in which a protein unravels and loses its native conformation, there by becoming biologically inactive. Denaturation occurs under extreme conditions of pH, salt concentration, and temperature.
Describe the characteristics that distinguish nucleic acids from the other major groups of macromolecules.
Nucleic acid is a biological molecule that allows organisms to reproduce polymers composed of monomers called nucleotides joined by covalent bonds between the phosphate of one nucleotide and the sugar of the next nucleotide.
Summarize the functions of nucleic acids.
Nucleic acids store and transmit hereditary information. List the major components of a nucleotide
*sugar covalent bond *phosphate group *one to four nitrogen bases
Distinguish between a pyrimidine and a purine.
Pyrimidine is characterized by a six membered ring made up of carbon and nitrogen atoms. Purine are larger, with the six membered ring fused to a five membered ring.
List the functions of nucleotides.
*building block of a nucleic acid *DNA information
Briefly describe the three-dimensional structure of DNA.
The DNA molecule is usually double – stranded, with the sugar phosphate backbone of the polynucleotide on the outside of the helix. In the interior are pairs of nitrogenous bases, holding the two strands together by hydrogen bonds. Chapter 6 An Introduction To Metabolism
Explain the role of catabolic and anabolic pathways in the energy exchanges of cellular metabolism.
Catabolic pathways release energy by breaking down complex molecules to simpler compounds and anabolic pathways consume energy to build complicated molecules form simpler ones.
Distinguish between kinetic and potential energy.
Kinetic energy is the energy of motion, and potential energy is energy that matter possesses because of its location or structure.
Explain, in your own words, the First and Second Laws of Thermodynamics.
The First law of thermodynamics mainly is that energy cannot be created or destroyed it is just always there, and the Second law explains that the energy just changes form (change in entropy).
Describe the function of ATP in the cell.
ATP is the cell’s energy shuttle; it powers cellular work by coupling exergonic to endergonic reactions.
List the three components of ATP and identify the major class of macromolecules of which it belongs.
N/A
Explain how ATP performs cellular work.
ATP drives endergonic reactions by transfer of the phosphate group to specific reactants, making them more reactive. Therefore, cells can carry out work, such as movement and anabolism.
Explain the relationship between enzyme structure and enzyme specificity.
The specificity of an enzyme is attributed to a compatible fit between the shape of its active site and the shape of the substance.
Explain the induced fit model of enzyme function and describe the catalytic cycle of an enzyme.
Induced fit brings chemical groups of the active site into positions that enhance their ability to work on the substrate and catalyze the chemical reaction. The catalytic cycle of an enzyme starts by the substrate binding to the active site to form an enzyme – substrate complex. In most cases, the substrate is held in the active site by weak interactions, such as hydrogen bonds and ionic bonds. Side chains (R groups) of a few of the amino acids that make up the active site catalyze the conversion of substrate to a product, and the product departs from the active site. The enzyme is then free to take another substrate molecule into its active site.
Explain how substrate concentration affects the rate of an enzyme-controlled reaction.
The enzyme binds to its substrate. While enzyme and substrate are joined, the catalytic action of the enzyme converts the substrate to the product of the reaction.
Explain how enzyme activity can be regulated or controlled by environmental conditions, cofactors, enzyme inhibitors and allosteric regulators.
Temperature is one environmental factor important in the activity of an enzyme. Up to a point, the velocity of an enzymatic reaction increases with increasing temperature. Cofactors are ions or molecules for some enzymes to function properly. Inhibitors reduce enzyme function and because allosteric regulators attach to an enzyme by weak bonds, the activity of the enzyme changes in response to fluctuating concentrations of the regulators.
Distinguish between allosteric activation and cooperativity.
Allosteric activation is the binding of an activator to an allosteric site which stabilizes the conformation that has a functional active site. Cooperativity is when an enzyme has two or more subunits and there is an interaction with a substrate molecule which triggers a favorable conformational change in all other subunits of the enzyme.