Exam #1 Short Answers Flashcards
Population
All individuals of a spp. living in
same are at same time
Community
All living organisms in a
particular ecosystem
Biosphere
All life & ecosystems on
Earth
Ecosystem
Consists of living & non- living parts of env.
Organs
Body part made of multiple tissues with a specific bodily function
Cell
Life’s fundamental unit of structure & function
Tissues
Group of cells working together to perform a specialized function
Evolution
heritable change in populations across generations (Framework for biology)
Give an example of any recent microorganism which has evolved through natural selection from the broad real-world scenario? Why understanding the mutations and
selective pressure that drive that mutation is important?
Covid and becasue understanding the mutations help us find a cure
Atom
smallest unit of an element that retains its chemical properties (Composed of subatomic particles)
Atomic Number
number of protons in an atom (Written as subscript (number on bottom) in front of chemical symbol)
Atomic Mass
the mass of protons & neutrons in
an atom (Written as superscript (number written on top) in front of chemical symbol)
Ion
an electrically charged atom that is the result of a gain or loss of electrons
Cation
ion that is formed when an atom loses electrons (positive charge)
Anion
ion that is formed when an atom gains electrons (negative charge)
Isotopes
atoms of the same element with different numbers of neutrons
Molecules
stable particle composed of 2 or more atoms joined by a covalent bond (Ex. Hydrogen gas (H2), Ozone
(O3), Water (H2O))
Compounds
particle composed of 2 or more different elements combined in a fixed ratio (Ex. carbon dioxide (CO2), Water
(H2O), Glucose (C6H12O6))
Valance Electrons
electron(s) in the outermost e- shell
What do Valance electrons do?
- Involved in forming bonds w/ other atoms
- Determine chemical properties of atoms
- Atoms lose, gain, or share e- to fill
valence shell
Electronegativity
A measure of an atom’s ability to attract shared electrons to itself. On the periodic table, electronegativity generally increases as you move from left to right across a period and decreases as you move down a group.
Ionic Bond
formed due to an attraction between
opposite charges of an anion and cation (Electrons are completed transferred between atoms and weak in presence of water)
H-Bond
a weak bond between a H with a
partial (+) charge & an electronegative atom (weakest type of bond)
Acid vs. Base
Acids: increases H+ conc. of a solution Bases: reduces H+ conc. of a solution
(increases OH- conc.)
Cohesion vs. Adhesion
Cohesion: Water is attracted to water, and Adhesion: Water is attracted to other substances
Identify and compare the properties of the bond between sodium and chloride (NaCl) with the bond between oxygen and hydrogen in water (H2O).
NaCL is ionic (electron completely transfered), O and H2O is a covalent bond (Elctron is shared)
organic compounds
compound in which C is covalently
bonded to more C’s to form backbone of molecule (Ex. methane (CH4), glucose (C6H12O6), ethane (C2H6))
isomer
compounds with the same molecular formula but different structures (Structure determines function, so different structure = different chemical properties 2 isomers of Butane (C4H10))
functional groups
chemical groups that affect molecular
function by being directly involved in chemical reactions
polymer
molecule composed of repeating subunits (monomers) of the same general type
mono, -di and -polysaccharide
Disaccharides: formed when dehydration reaction joins two monosaccharides (Formed via a glycosidic bond), Polysaccharides: – >2 monosaccharide units (linked by
glycosidic bonds)
saturated fat
maximum # of hydrogen atoms in the fatty acid chains (Solid at room temp and Often from animal sources)
unsaturated fat
one or more double bonds in the fatty acid chains (Liquid at room temp and often from plant sources)
Phospholipid
amphipathic lipids with 2 fatty acid chains (Component of cell membranes (assemble into bilayer))
steroid
carbon skeleton consisting of four fused rings (No fatty acids in structure)
amino acids
monomers of proteins (3 main components: Amino group, Carboxyl group, Side chain (unique R group))
proteins
macromolecules made up of chains of amino acids (monomers)
nucleic acid and its component
polymers of linked nucleotides (monomers) (3 components: 5-carbon sugar, a phosphate group and a nitrogenous base)
Describe the four levels of organization of protein and list the type(s) of bond(s) involved in
establishing each structural level
Primary (1) Structure – unique sequence of amino acids
Secondary (2) Structure – consists of coils & folds of amino acid chain resulting from hydrogen bonds
Tertiary (3) Structure – 3D structure of each individual polypeptide chain (Formed by interactions between side chains)(H-Bonds and Ionic Bonds and Disulfic bond)
Quaternary (4) Structure – the overall structure (shape) of a complete protein (Formed by interactions between 2 or more polypeptide chains) (Same as 3 structure)
Prokaryotic cell
belong to Domains Bacteria & Archaea (No nucleus, No membrane-bound
organelles, Most have cell walls & ribosomes, Smaller than eukaryotic
cells)
eukaryotic cell
belong to Domain Eukarya (Kingdoms Fungi, Plantae, Animalia, & “Protista”) (Membrane-bound nucleus, membrane-bound organelles, Some have cell walls, Larger than prokaryotic cells)
mitochondria
sites of cellular respiration (Found in nearly all eukaryotic cells, Enclosed by a double membrane, Contain own DNA in circular loop, Grow & reproduce independently)
chloroplast
sites of photosynthesis (Found in plant cells & algae, Enclosed by a double membrane, Contain their own DNA in a circular loop, Grow & reproduce independently)
nucleus
contains most of the DNA in a eukaryotic cell
ribosome
use information from DNA to make proteins
vesicle
a small, fluid-filled sac or cavity in a plant or animal
endoplasmic reticulam
Extensive network of membranes (Encircles nucleus & extends
through cell Two Types: rough ER and smooth ER)
Rough Endoplasmic Reticulum
studded with ribosomes
on outer surface (Aids in protein synthesis, Distributes transport vesicles that contain proteins)
Smooth Endoplasmic Reticulum
lacks ribosomes on outer surface (synthesizes lipids, Metabolizes carbohydrates, Detoxifies drugs & poisons)
golgi complex
a cell organelle that processes, sorts and packages proteins and lipids for use inside and outside the cell
lysosome
are membranous sacs of enzymes that can: digest macromolecules, Break down “food” taken in by cell, Destroy bacteria, and Destroy damaged organelles
microtubule
guide movement of organelles & separate chromosomes during cell division
Write 2 evidences that support the endosymbiotic theory
(1)mitochondria and chloroplasts have their own circular DNA, similar to bacteria, and (2) these organelles replicate independently through a process called binary fission
Use the cell diagram to answer the following questions
Diagram
