Science Flashcards
Elements
A molecule composed of one kind of atom; cannot be broken into simpler units by chemical reactions.
Compounds
2 or more elements chemically combined
Mixtures
A combination of two or more substances that are not chemically combined
Sub-atomic particles
protons, neutrons, electrons
proton
Postively charged particles
Neutron
Neutral charged particle
electron
negatively charged particles
mass (amu)
atomic mass unit
atomic number
number of protons of the atom
atomic mass
number of protons and neutrons
Isotopes
Atoms of the same element with different numbers of neutrons
changing the number of neutrons…
Doesn’t change the element.
Changing the number of protons…
changes the element
Mitosis
cell division in which the nucleus divides into nuclei containing the same number of chromosomes. results in 2 nuclei and occurs in non reproducing cells.
Meiosis
a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores. Cell division that produces reproductive cells in sexually reproducing organisms.
Gametes
sex cells
homologous chromosomes
Pair of chromosomes that are the same size, same appearance and same genes.
Haploid
having a single set of unpaired chromosomes
Diploid
2 sets of chromosomes
PMAT
prophase, metaphase, anaphase, telophase
PMAT
cell division process
Mitosis goes through pmat…
once
Meiosis goes through pmat
Twice
Chromtaid
one half of a duplicated chromosome
homologous pair
a pair of chromosomes, one from each parent, that have relatively similar structures and gene values
Mitosis has
chromtaid
Meiosis had
Homologous pairs
Prophase (Before)
first and longest phase of cell division process, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
Metaphase (meet in middle)
Chromosomes line up in the middle of the cell
Anaphase (Away)
Phase of pmat in which the chromosomes separate and move to opposite ends of the cell
Telophase (two cells)
After the chromosome seperates, the cell seals off, Final Phase of pmat
paternal copies
Father genes
Maternal copies
Mother genes
DNA
deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.
Chromosomes
threadlike structures made of DNA molecules that contain the genes
Genes
A segment of DNA on a chromosome that codes for a specific trait. (Characteristics)
homozygous dominant
Both alleles (factors) for a trait are the same and dominant (AA)
Heterozygous
having two different alleles for a trait(Aa)
homozygous recessive
Both alleles (factors) for a trait are the same and recessive (aa)
The word atom means
indivisible
The word atom means
indivisible
isotope
Atoms of the same element that have different numbers of neutrons
Radioisotopes
An isotope that has an unstable nucleus and undergoes radioactive decay. Losing neutrons to become more stable.
radioactive decay
The breakdown of a radioactive element, releasing particles and energy
raditation
The transfer of energy by electromagnetic waves
half-life
length of time required for half of the radioactive atoms in a sample to decay
Ions
positively and negatively charged atoms
alkai metals
reactive elements of Group 1 in the periodic table, soft with low melting points
Halogens
Contains nonmetals, 7 valence electrons in it’s outermost energy level. Very reactive
Noble gases
Elements in group 8A of the periodic table. Have no charge and are gases under normal conditions. (Helium, Neon, Argon, Krypton, Xenon, Radon). stable
The number of shells present in an element is equal to
The period number of the element
Dominant genotype
AA
Recessive genotype
aa
Genotype
genetic makeup, what genes the person carries
phenotypes
Physical expressions of genetic trait, what the person actual has. eg. brown hair
