Highlighting Guide=Important terms
General Biology Exam 1 Study Guide Ch 1-4 Ch 1. Biology Exploring Life
Biology- the scientific study of life (or living organisms)
Cells- the structural and functional units of life.
Characteristics of Life
-Reproduction: organisms reproduce their own kind
-Growth and Development: inherited information encoded in DNA controls the pattern of growth and development of all organisms
-Response to the environment: All organisms respond to environment stimuli.
-Energy Processing: Organisms take in energy and use it to power all their activities
-Regulation: Organisms have regulatory mechanisms that maintain a beneficial internal environment
-Evolutionary Adaptation: Adaptations, such as a red panda’s warmth providing tail, evolve countless generations as individuals with heritable traits that are best suited to their environments have greater reproductive success
Life can be Organized into Three Domains
1. Bacteria- Are considered a mesophilic- they thrive in moderate environments.
2. Archaea- thrive in harsh extreme environments such as boiling springs or artic cold for example
3. Eukarya- all organisms that consist of more complex cells; are grouped in the domain of Eukarya. These include…
*Protists- diverse collection of mostly single-celled organisms.
*Fungi- members of this group mostly decompose organic wastes and absorb the nutrients into their cells.
*Plantae (Plants)- produce their own food by using photosynthesis; they are multicellular
* Animals- grouped into kingdom animalia -obtain food by eating other organisms. Example (a butterfly drinking nectar from a flower).
Biologist study life across a very broad range of scales, from the molecules in a cell to the entire living planet. They divide this into a series of structural levels.
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The Hierarchy organization
1. Biosphere-all life on earth; places where life exist
2. Ecosystem- all the organisms in a particular area. (such as soil, water and light)
3. Community- all the organisms in an ecosystem.
4. Population- all the individuals of a species living in a community. 5. Organism- an individual living thing
6. Organs and organ systems: Body parts that perform a specific function. Several organs may cooperate in an organ system. 7. Tissue- A group of similar cells performing a specific function. 8. Cell- the fundamental structural and functional unit of life. 9. Organelle- membrane-enclosed structure in a cell. Don't forget about the age old question of what institutionalized system of communication that conveys information and
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10. Molecule- A chemical structure consisting of two or more units called atoms.
Process of science
∙ Science is a way of knowing-an approach to understanding the natural world.
Hypothesis- a proposed explanation for a set of observations.
Theory- supported by a large and usually growing body of evidence, and has not been contradicted by any scientific data
Data- recorded observations; the evidence on which scientific inquiry is based.
Controlled Experiment- scientific test often carried out by controlled conditions. A treatment group knows their being observed.
Evolution is the Core Theme of Biology
Evolution- the process of change that has transformed life on earth from its earliest forms to the vast array of organisms living today.
-Evolution was studied by both Charles Darwin and Alfred Wallace.
-Charles Darwin Came up with natural selection and published a book called “On the Origin of species” Although both men knew about the concept, Darwin published his book first and got accredited. We also discuss several other topics like organizational opportunities means what?
Natural Selection- a process in which individuals with certain inherited traits are more likely to survive and reproduce than are individuals that do not have those traits.
The Theme of Life Depends on the Flow of Information
DNA- encodes a cell’s instructions for all a cell’s functions; heritable information.
-made up of two long strands called strands.
- They are coiled together in to a double helix. Compared to RNA which has single Stranded helix
RNA- A type of nucleic acid consisting of nucleotide monomers with ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U).
-Single stranded helix, unlike DNA that has a double stranded helix
-Strands are made up of four different kinds of chemical building blocks called nucleotides.
Genes- Specific sequences of these four chemical letters encode precise information in units of inheritance called gens, which are typically hundreds of thousands of “letters” long We also discuss several other topics like What is gaussian elimination?
-most genes, the sequence of the letters provides a blueprint for making a protein, and proteins are the major players in building and maintaining the cell and carrying out its activities.
Transcription- the synthesis of RNA on DNA template
Translation- the synthesis of a polypeptide using genetic information encoded in an mRNA
Organisms are composed of elements, usually combined into compounds
Matter- is defined as anything that occupies space and has mas.
Element- is substance that cannot be broken down to other substances by ordinary chemical means.
Compound- is a substance consisting of two or more different elements combined in a fixed ratio.
∙ Elements Essential for life
-Oxygen (most abundant), Carbon (most abundant on a dry weight bases), hydrogen- Components of all organic molecules, especially carbohydrates.
-Sodium, Chlorine- nerve impulse transmission
-Magnesium- enzyme cofactor
make up the least amount of the human body weight. The most important of these elements are
* Fe (Iron)- oxygen transport by blood; prevents anemia. * I2 (Iodine)- iodized salt; for thyroid function; prevents goiter *F2 (fluorine)- in toothpastes & water, prevents tooth decay. Also present in vitamins, preservatives and colorings. Don't forget about the age old question of How did the Camp David accords affect the US?
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Atoms consist of protons, neutrons
∙ Each element has its own type of atom, which is different from the atoms of other elements.
Atom- the smallest unit of matter that still retains the properties of the elements
Proton- is a subatomic particle with a single positive electrical charge Electron- is a subatomic particle with a single negative charge
Neutron- is electrically neutral
Nucleus- made up of protons and neutrons, in the center of an atom
-The attraction between the negatively charged particles and the positively charged particles holds the electrons near the nucleus.
All atoms of a particular element have the same unique number of protons. This number is the element’s atomic number.
An atoms mass number is the sum of the number of protons and neutrons in its nucleus.
Isotopes- have the same number of protons but a different number of neutrons, they behave the same in chemical reactions.
Radioactive isotope- is one in which the nucleus decays spontaneously, giving off particles and energy.
Electrons can be located in different electron shells with characteristic distance from the nucleus.
Ch 3. The Molecules of Cells
The 3 Main types of Bonds
-When two atoms with two incomplete outer shells interact, they may give up or accept, or share electrons, so that both electrons end up with outer shells. These interactions usually result in atoms staying close together called a chemical bond.
-The actual transfer of an electron between atoms results an attraction called an ionic bond.
-In a covalent bond, atoms do not transfer electrons but actually share electrons between them. Sharing one or more pairs of electrons between them. Sharing one or more electrons.
-In each case, an atom has become an ion- an atom or molecule with an electrical charge resulting from a gain or loss of one or more electrons.
One of the most important type of weak bonds is the hydrogen bond.
Polar molecule- that is, it has an unequal distribution of charges. It is slightly negative at oxygen end of the molecule (polar)
The tendency of the same molecules sticking together is called cohesion. Adhesion is the clinging of one substance to another (different kinds of molecules sticking together.)
Waters hydrogen bonds moderate temperature
Evaporative cooling occurs because the molecules with the greatest energy (the hottest ones) leave.
Water is the Solvent of life
-A solution is a liquid that is a mixture of two or more substances.
If there was a salt and water mixture in a glass, the solvent would be the thing dissolving the salt (water) the solute would be the thing getting dissolved (salt). This is an example of an aqueous solution because water is the solvent.
Life’s molecular diversity is based on the properties of carbon Carbon based molecules are called organic compounds
The number of electrons in the outermost shell determines an atoms chemical properties.
Isomers are compounds with the same formula but different structural arrangements.
Hydrocarbons are molecules only consisting of carbon and hydrogen. Hydroxyl groups consist of a hydrogen atom bonded to an oxygen atom
Carbonyl groups is when a carbon atom is linked by a double bond to an oxygen atom.
A carboxyl group consists of v=carbon double bonded to an oxygen atom and also bonded to a hydroxyl group
An amino group has a nitrogen bonded to two hydrogens. It can act as a base as well.
A phosphate group consists of a phosphorus atom bonded to four oxygen atoms. It is usually ionized.
A methyl group consists of a carbon bonded to three hydrogen atoms.
The Chemistry of life is sensitive to acidic and basic conditions ∙ Some chemical compounds contribute additional H+ bonds to an aqueous solution (Acidic bonds) while other contribute H- bonds to a solution which reduces the hydrogen ion concentration of a solution (A base).
Fats and lipids are mostly storage molecules.
Lipids- are a diverse group of molecules classified together because they share one trait: they do not mix well with water. They are hydrophobic (water fearing).
A fat is a large lipid made of two smaller molecules (glycerol and fatty acids) -Consists of a carboxyl group
An unsaturated fatty acid has hydrocarbon that contains one or more double bonds.
A Saturated fatty acid has no double bonds in its hydrocarbon chain. -Partially hydrogenated
The product of hydrogenation creates trans-fat which is a form of fat that causes health risks.
Phospholipids ad steroids are important lipids with a variety of functions
Cells could not exist without Phospholipids, they are the major component of a cells membrane.
Steroids are lipids in which the carbon skeleton contains four fussed rings.
Cholesterol is a common component in animal cell membranes and is the precursor for making other steroids including sex hormones.
Amino Acids all have an amino group, and a carboxyl group (which makes it an acid) and alpha carbon and an R-group. The R-group changes, which distinguished the different type of amino acids…
1. Leucine- nonpolar
2. Serine- polar
3. Aspartic- polar
-Cells join amino acids together in dehydration reaction that links the carboxyl group of one amino acid to the amino group of the next amino acid as water molecules are removed. Next a covalent bond is made and the linkage of this is called a peptide. If two amino acids come together to form one amino acid, it is called a dipeptide.
-A polypeptide is a chain of amino acids.
Ch 4 A Tour of the Cell
The cell theory states that all living things are composed of cells and that all cells come from other cells.
Electron microscope (EM)- focuses abeam of electrons through a specimen or onto its surface.
Light microscope (LM)- visible light is passed through a specimen Scanning Electron Microscope (SEM)- study detail architecture surface Transmission electron microscope (TEM)- study internal detail of a structure Cells
Plasma membrane or cell membrane forms a flexible boundary between living and nonliving surface surrounding and is very thin.
Prokaryotic cells have no nucleus or organelles and was the first to evolve on earth. Eukaryotic cells contain membrane bound organelles and can be single, or multi celled like humans.
Cells consist of….
Cytosol- jelly-like fluid
Chromosomes- carry genes made of DNA
Ribosomes- rib-like make proteins, carry out instructions from genes to make proteins
-consist of smooth endoplasmic reticulum and rough endoplasmic reticulum.
Cytoplasm- inside of the cell
Nucleoid- only in the eukaryotic cell
Nucleus- contains the cell’s genetic instructions encoded in DNA. Chromatin- helps cells divide, appears within the nucleus
Nuclear envelope- encloses the nucleus, double membrane Nucleolus- place where a special type of RNA called rRna is made. Cytoskeleton- provides support for cell
Contractile Vacuoles- fresh water protist that eliminate excess water Plant vacuoles- function in storage of nutrients and waste products -provides hydrastic pressure for cell growth and support.
In animal cells, lysosomes are present. They are a membranous vesicle containing hydrolytic enzymes that aid in breaking down or digestion of food particles and organelle recycling.