Flashcards in Biology Lecture Final Deck (90):
An explanation for a very general class phenomena or observations
All organisms are made of cells and all cells come from pre-existing cells. This came about in the mid 1800s
The process by which species have changed and diversified since life first arose. Explains unity, all living things share the same characteristics and the diversity if life.
Natural selection occurs when two conditions are met-
1. Individuals within a population vary in characteristics that are heritable ( traits that can be passed on to offspring). A population is defined as a group of individuals of the same species.
2. Certain versions of these heritable traits help individuals survive better or reproduce more than other versions
Changes in populations that occur when humans select certain individuals to reproduce the most offspring
Cells have a nucleus. Are multicellular. Animals, fungi and plants
Do not have a nucleus. One celled. ex: Bacteria and archaea
To name and classify organisms
Taxon (taxa, plural)
Any named group
Three domains of life bacteria, archaea and eukarya
Phylum (phyla, plural)
A term to refer to major linages within in domain.
Taxon- domain- phylum
1735. Swedish botanist came established a system for naming species. A two part name made for the organism. First part to the name is called the genus and the second part of the name identifies the organisms species. Ex: homo (genus) sapiens (identifies species)
Specifies what we should observe when the hypothesis being tested isn't correct
Leading explanation for the origin of life.
Inputs of energy on early earth led to the formation of increasingly complex carbon containing substances, culminating in a compound that could make a copy of itself or self replicate.
What are the four molecules that make up 96 percent of all matter found in organisms.
Hydrogen, carbon, nitrogen and oxygen
The number of protons of an element
The sum of protons and neutrons
Forms of an the same element with different numbers of neutrons
Results when two atoms share electrons in order to have a completed two electrons.
A group of atoms together. When it contains atoms of more than one element it is called a compound. There are two types if chemical bonds: ionic and covalent
Nonpolar covalent bond
Because carbon and hydrogen have approximately equal electronegativity the electrons in a C-H bond are shared equally
Polar covalent bond
Atoms that tend to be mor electronegative tend to hold shared electrons more tightly. Meaning atoms on both sides of the bind are partially charged.
Forms when two atoms are held together by the attraction between opposite charges. This makes ions; charged atoms.
Positively charged ion. Has electrons taken away from it
Negatively charged ion. Electrons are added.
Substances that interact with water. Ions and polar molecules react with water.
Substances that do not interact with water. Compounds that are uncharged and non polar. Do not react with water through hydrogen bonding.
Binding between like molecules
Bindings between unlike molecules
Heat is absorbed during reaction or a process
Releases heat. Transformation of water vapor to liquid water.
The energy if motion. Molecules always have kinetic energy because they are constantly in motion
Kinetic energy of molecular motion
Formaldehyde, hydrogen cyanide and other simple organic compounds reacted to form mid sized molecules called amino acids, nitrogenous bases and sugars. Oparin- haldane theory: these molecules accumulated in the shallow waters of the ancient ocean forming a complex solution.
Amino acids like together and make?
Nucleotides attach together and make?
Simple sugars link together to form?
Molecular subunits (monomers)
Amino acid, nucleotide and sugar.
These monomers link together and make polymers.
Is the linking process of monomers making a polymer. Ex : amino acids polymerize to form proteins
A very large molecule made up of smaller molecules joined together.
Condensation reactions aka dehydration reactions
Monomers polymerize by this.
The reverse reaction of condensation. Breaks polymers apart by adding water molecule. The water molecule reacts with the bond linking the monomers, separating one monomer from the polymer chain
C-N bond that results from this condensation reaction.
When amino acids are linked by peptide bonds into a chain, the amino acids are referred to as residues and the resulting molecule
Polypeptides that contain 50 or more amino acids
300 million copies if it in each red blood cell. Helps being oxygen from the lungs to the rest of the body.
It is a protein also in red blood cells. Important for moving carbon dioxide from cells to FB lungs and breathed out
A protein that functions as a catalyst. Many proteins are specialized to catalyze or speed up, chemical reactions. Ex: carbonic anhydrase, salivary amylase.
The location where substrates bind and react became known enzymes active site
Carbohydrate or sugar
Encompasses the monomer called monosaccharides ( one sugar)
Each monosaccharide has a number of carbon atoms present. Each time they vary.
Name for three-carbon, name for five carbons and a six carbon
Pentose: ribose acts as a building block for nucleotides
Hexose: glucose in the bloodstream.
Makes up the bulk of the brain. Is divided into left and right hemispheres and is involved in conscious thought and memory.
Coordinates complex motor patterns.
Relays sensory messages that go to the cerebellum and controls homeostasis
Connect the brain to the spinal cord and is the autonomic center for regulating the heart, lungs and digestive system
Four major lobes.
The frontal lobe, the parietal lobe, the occipital lobe and the temporal lobe.
Two hemispheres are connected by a thick band of axons
"Rest and digest"
Conserve or restore energy. Constrict pupils, stimulate salvation, slow heart beat, constrict hear beat, constrict air ways, stimulate stomach activity, inhibit release of glucose; stimulate gallbladder.
Sympathetic nervous system
Typically prepare organs for stressful "fight or flight" situations. Speed up heart rate, stimulate the release of glucose from the liver and inhibit action by digestive organs
Carbohydrate that plant cells use. Monosaccharide are stored as starch.
Performs the same storage role in animals that starch performs in plant cells. In humans it is stored in the liver and muscles. Glycogen is broken down into glucose when you work out.
Is a protective sheet that occurs outside the membrane. In algae, bacteria, fungi. Composed if primarily of one it more polysaccharides.
Major comment to the cell wall. Polymer of b-glucose monomers.
Is a polysaccharide that stiffens the cell walls of fungi. Important component of the external skeletons of insects and crustaceans.
A polysaccharide that gives bacterial cell walls strength and firmness.
Separates life from no life. It is a layer of molecules that surrounds the cell interior and separates it from the external environment.
Molecules that contain only carbon and hydrogen. Hydrocarbons are nonpolar because electrons are shared equally. Lipids are this and are not soluble in water
Are composed of three fatty acids. Linked to a 3 carbon molecule called glycerol.
A family of lipids. Cholesterol.
Consist of a glycerol that is linked to a phosphate group.
Are created when two sheets of phospholipid molecules align. Hydrophilic heads in each layer face surrounding solution while hydrophobic tails face one another inside the bilayer. Hydrophobic side interact with water
Of a structure is its tendency to allow a given substance to pass across it. Only certain molecules and ions can go thru a lipid bilayer.
Means that some substance cross hype membrane more easily that other substances can. Small nonpolar molecules move across bilayer a quickly. While large molecules and charges substances cross the membrane slowly, if at all
Hydrocarbon chains without double bonds. This means a lot if hydrogen atoms can attach to the carbon skeleton
Hydrocarbon chain contains a double bond. Fewer than the maximum number of hydrogen atoms ate attached
Cell will shrink and the membrane will shrivel
Incoming water will cause the cell to swell or even burst
If solute concentrations at sequel on either side the membrane will be able to maintain itself. When the outside does not affect the membranes shape.
Special channels in the cell membrane:
Ion channels: ions cross membranes thru specialized membrane proteins. Diffusion. High concentration to low concentration
Channel proteins: subsequent research has shown that cells have many different types of pore like. Is selective, allows in particular types of ion or small molecules
Awuaporins: allow water to cross the plasma membrane
Contains the chromosomes and functions as an information storage a d processing center.
Enclosed the nucleus. Complex double membrane. Studded with pore like openings.
Where DNA is held within the nucleus.
On the nuclear envelope, membrane bound sacs. Extends from envelop to the cytoplasm.
Rough endoplasmic reticulum (rough ER)
Are ribosomes that attach to the membrane. Synthesize proteins that will be inserted into plasma membrane. Some of these proteins carry messages to other cells, some act as membrane transport proteins
Smooth endoplasmic reticulum (smooth ER)!
Contains enzymes that catalyze reactions involving lipids.
The products of the rough ER pass thru here before they reach their final destination. Consists of Flattened, membranous sacs called cisternae.
Least inclusive to most inclusive. Classification categories
Species, genus, family, order, class, phylum, kingdom and domain
Electrons that share between two atoms in a covalent bind are not always shared equally. Atoms different their electronegativity. Is related to size, larger atoms tend to have a higher affinity and electronegativity.
Ribose and deoxyribose
Both have five carbon atoms. (Polysaccarides) Are significant because they are found in nucleic acids RNA and DNA.
Fats (bacon fat, lard and butter) and oils (such as corn oil, olive oil and coconut oil). In animals fats are used for insulation and long-term energy storage