midterms (1) Flashcards
● A change in matter from one
physical state to another physical
state
● Reversible change
● Involves a change in the phases of
matter
physical change
● Atoms rearrange to create a new
substance
● Irreversible change
● Involves a change in chemical
bonds
chemical change
Carbon dioxide in solid form (CO2)
dry ice
6 examples of physical change
● Freezing (liquid → solid)
● Melting or fusion (solid → liquid)
● Condensation (gas → liquid)
● Vaporization (liquid → gas)
● Sublimation (solid → gas)
● Deposition (gas → solid)
2 Ammonia gas (NH3)
Nitrogen gas (N2) + 3 Hydrogen gas (H2)
6 examples of chemical change
● Rusting of metals
● Combustion
● Metabolism of food
● Burning
● Color change
● Odor change
● Sum of all chemical reactions within a living organism
● Refers to a specific set of chemical reactions occurring
at the cellular level
○ e.g. sugar metabolism and fat metabolism
metabolism
2 key players in metabolism
enzymes and adenosine triphosphate
○ Proteins that act as catalyst to speed up reactions
○ Catalyze reactions for specific molecules called
enzymes, substrates
Substrates are transformed into new
substances called
products
A molecule that is a common energy source for all cells
adenosine triphosphate
A form of electromagnetic radiation that is visible to the eye. The energy of ___ is packaged in photons.
light energy
example of light energy
during photosynthesis
The transfer of kinetic energy from one object to another or from an energy source to an object.
heat energy
example of heat energy
organisms at constant body temperature
Energy possessed by an object due to its motion or its position relative to other objects.
mechanical
example of mechanical energy
muscle contraction such as walking
Potential energy stored in the electrons of
molecules. When bonds are broken and
rearranged, energy may be released.
chemical potential
example of chemical potential
The covalent bonds in organic molecules, such as glucose and ATP, store large amounts of energy. When bonds are broken in larger molecules to form smaller molecules, the energy that is released can be used to
drive cellular processes.
The movement of charge or the separation of charges can provide energy. Ion concentration across a membrane constitutes an electrochemical gradient, which is a source of potential energy.
electrical / ion gradient
example of electrical / ion gradient
During oxidative phosphorylation, an H+ gradient provides the energy to drive ATP synthesis.
Specific region of the surface of
enzyme molecule
active site
Material obtained as a result
from the chemical reaction
product
Chemical reactants where
enzymes bind to
substrates
Chemical reactions coordinated with each other and often occur in a series of steps
metabolic pathways
● Results in the breakdown of larger molecules into smaller ones
● Releases energy in the process
● Generally hydrolytic
○ Uses water
● Exergonic
○ Produce more energy than they consume
catabolic
● Results in the synthesis of larger molecules from smaller precursor molecules
● Uses energy in the process
● Often involve dehydration synthesis reactions
○ Releases water
● Endergonic
○ Consume more energy than they produce
anabolic
Comprises the metabolic reactions that a cell uses to get energy from food molecules and
release waste products
cellular respiration
Breakdown of glucose (compound with 6 carbon atoms) into two molecules of pyruvate (compound with 3 carbon atoms). Covalent bonds are broken and rearranged, and some of the energy released during the breakage of covalent bonds in glucose is harnessed to synthesize ATP.
glycolysis
Breakdown of carbohydrates to carbon dioxide.
citric acid cycle
Removal of electrons from nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FADH2 ) and ATP is made by the phosphorylation of ADP.
oxidative phosphorylation
Breakdown of organic molecules in the absence of oxygen by using a final electron acceptor that is something other than oxygen.
anaerobic respiration
Breakdown of organic molecules to produce energy without any net oxidation of an organic molecule. Does not use electron transport chain to produce energy from anaerobic environment.
fermentation
Key Roles of
Cell Division
● The ability of organisms to reproduce
best distinguishes living things from
nonliving matter
○ Cell reproduction for unicellular
organisms
■ Reproduces the organism
○ Cell reproduction for
multicellular organism
■ Involved in growth, repair, and
formation of sperm and egg
cells
● Cell division is an integral part of the
cell cycle, the life of a cell from
formation to its own division
All of the genetic material in an organism
genome
prokaryote
single, double-stranded dna
loop or cicrular dna
contained in nucleoid
eukaryote
multiple, double-stranded dna
linear dna bound w proteins
contained in nucleus
Each chromosome consists of one very long, linear DNA molecule associated with many proteins
chromosome
The entire complex of DNA and
proteins that is the building
material of chromosomes
chromatin
organization of eukaryotic chromosome
Amino acid portion of histones create (+) charges Phosphate group of DNA forms (-) charges
The DNA molecule carries several hundred to a few thousand ____,
the units of information that specify the organism’s inherited traits
genes
● Represented differently in females than in males
● Functions in sex determination
sex chromosomes
● Chromosomes that are alike
● Not involved in determining sex
● Gr. autos, self + soma, body
autosomes
central dogma of molecular bio
replication, transcription, translation
dna to dna
replication
dna to rna
transcription
rna to protein
translation
The life of a cell, from its beginning until it divides to produce the new generation of cells
cell cycle
● The shortest part of the cell cycle
● Includes mitosis and cytokinesis
mitotic phase
● Accounts for about 90% of the cell cycle
● Time of cell growth, DNA synthesis, and preparation for
the next mitotic division
interphase
● Early growth phase of the cell
○ Increase cell size
○ Synthesize proteins, lipids, and carbohydrates
G1 (first growth or gap 1)
● Growth continues and involves DNA replication
S (DNA synthesis)
● Prepares the cell for division
● Replication of mitochondria and other organelles
● Synthesis of microtubules and protein
○ Sister chromatids begin to coil and more compact
○ Volume of cell doubled
G2 (second growth or gap 2)
● Also known as ___
○ The replication and division of the nucleus of a eukaryotic cell in preparation
for ____, the division of the cell and cytoplasm into halves that each
contain a nucleus
○ Produces _____ daughter cells, ______
mitosis,
karyokinesis, cytokinesis, diploid (2n), containing two sets of chromosomes
● Consists of fibers made of microtubules and associated proteins that controls chromosome movement
mitotic spindle
● Where spindle microtubules starts to assemble
● Single centrosome duplicates in two during
interphase in animal cells
● Move apart during prophase and prometaphase of
mitosis
centrosome
● Made up of proteins that have assembled on
specific sections of DNA at each centromere
● Face in opposite directions of chromosomes
● Some of the spindle microtubules attach to the
kinetochores during prometaphase
kinetochore
● Identical pair of chromosomal DNA strands
sister chromatids
The narrow “waist” of the duplicated chromosome, where the two chromatids
are most closely attached
centromere
> Nuclear envelope
encloses the nucleus
Centrosomes formed
G2 of interphase
> Chromatin fibers
become more tightly
coiled, condensing into
discrete chromosomes
Nucleolus disappear
prophase
> Kinetochores appear at
the centromeres
Mitotic spindle
microtubules attach to
kinetochores
Centrosomes move
toward opposite poles
prometaphase
> Fully developed mitotic
spindle
Chromosomes are lined
up at the metaphase
plate
Each sister chromatid is
attached to a spindle
fiber originating from
opposite poles
metaphase
> Cohesin proteins
binding the sister
chromatids together
break down
Sister chromatids (now
called chromosomes) are
pulled toward opposite
poles
Non-kinetochore
spindle fibers lengthen,
elongating the cell
anaphase
> Chromosomes arrive at
opposite poles and begin
to decondense
Nuclear envelope
material surrounds each
set of chromosomes
The mitotic spindle
breaks down
telophase
● Occurs in animal cells by a process
known as cleavage
cytokinesis
○ The first sign of cleavage is the
appearance of ____,
which is a shallow groove in the
cell surface near the old
metaphase plate
cleavage furrow
The cleavage furrow deepens until
the parent cell is pinched in two,
producing two completely
separated cells, each with its own:
■ Nucleus
■ Cytosol
■ Organelles
■ Other subcellular structures
● A type of cell division in sexually reproducing organisms
which produces ____, _____
○ Interphase
○ Meiosis I
○ Meiosis II
meiosis
haploid (n) daughter cells, containing
only one set of chromosomes
○ The maternal and paternal copies of the same chromosome
homologous chromosome
○ Two replicas of a single chromosome held together at their centromeres by cohesin proteins after DNA replication
sister chromatids
● A haploid reproductive
cell that is formed by
meiosis
● ____ unite during
sexual reproduction to
produce a diploid
zygote
gametes
● Unit of hereditary
information consisting
of a specific nucleotide
sequence in DNA (or
RNA, in some viruses).
genes
● Plural: loci
● Specific location of a
gene on a certain
chromosome
locus
