Download Unit 5 vocab

Unit 5 - Cell Growth and Division
DNA, Mitosis, Meiosis, & Intro to genetics
Term
Nucleotides
Definition
A monomer that forms DNA and has a phosphate
group, a sugar, and a nitrogen- containing base
Double helix
Model that compares the structure of a DNA
molecule, in which two strands wind around one
another, to that of a twisted ladder.
Base pairing rule
Replication
DNA Polymerase
Cell cycle
Mitosis
Rule that describes how nucleotides form bonds in
DNA, Adenine (A) always bonds with thymine (T) and
guanine (G) always bonds with cytosine (C)
The process by which a strand of DNA and all of its
genetic information are copied.
Enzyme that makes bonds between nucleotides,
forming an identical strand of DNA during replication
It is a pattern of growth, DNA replication, and cell
division that occurs in a eukaryotic cell
The process by which a cell divides its nucleus and its
contents
Synthesis
Cytokinesis
Chromosome
The process by which the cytoplasm of a cell divides
Long, continuous thread of DNA that consists of
numerous genes and regulatory information.
Term
Histone
Definition
Protein that organizes chromosomes and around
which DNA wraps itself
Chromatin
Loose combination of DNA and proteins that is
present during interphase of cell replication
Chromatid
one half of a duplicated chromosome
Centromere
Region of condensed chromosome that looks
pinched: it is where spindle fibers attach during
meiosis and mitosis
Telomere
Repeating nucleotide at the ends of DNA molecules
that do not form genes. They help prevent the loss of
genes
Prophase
First phase of mitosis when chromatin condenses, the
nuclear envelope breaks down, the nucleolus
disappears and the centrosomes and centrioles
migrate to opposite sides of the cell
Metaphase
Second phase of mitosis when spindle fibers align the
chromosomes along the cell equator (the middle of
the cell)
Anaphase
Third phase of mitosis during which chromatids
separate and are pulled to opposite sides of the cell
(anaphase- apart)
Telophase
Last phase of mitosis when a complete set of identical
chromosomes is positioned at each pole of the cell,
the nuclear membranes start to form, the
chromosomes begin to uncoil, and the spindle fiber
Growth factors
A broad group of proteins that stimulate cell division
Term
Apoptosis
Definition
Programmed cell death
Cancer
Common name for a class of diseases characterized
by uncontrolled cell division
Benign
Having no dangerous effect on health, especially
referring to an abnormal growth of cells that are not
cancerous
Malignant
Cancerous tumor in which cells break away and
spread to other parts of the body, causing harm to the
organisms health
Metastasize
To spread by transferring a disease-causing agent
from the site of the disease to other parts of the body
carcinogen
Substance that produces or promoted the
development of cancer
Asexual reproduction
Process by which offspring are produced from a single
parent; does not involve joining of gametes (ie: no
sperm combining with egg)
Binary fission
Form of asexual reproduction in which a cell divides
into two equal parts
Budding
a form of asexual reproduction in which a new
individual develops from some generative anatomical
point of the parent organism
Fragmentation
A form of asexual reproduction wherein a parent
organism breaks into fragments, each capable of
growing independently into a new organism
Term
Vegetative reproduction
Definition
Asexual reproduction in which a stem leaf or root will
produce a new individual when detached from a
parent plant
Somatic cells
Cell that makes up all of the body tissues and organs,
except for gametes
Gamete
Sex cell; an egg or sperm cell
Homologous
chromosomes
Chromosomes that have the same length,
appearance, and copies of genes, although the alleles
may differ
Autosome
Chromosome that contains genes for characteristics
not directly related to the sex of the organism
Sex chromosome
Chromosome that directly controls the development
of sexual characteristics
Sexual reproduction
Process by which two gametes fuse and produce
offspring that are genetically a mixture of both
parents
Fusion of an egg and sperm cell
Fertilization
Diploid
Cell that has two copies of each chromosome, one
from an egg and one from a sperm
(think diploid =double)
Haploid
Cell that has only one copy of each chromosome
(Think haploid =half)
Term
Meiosis
Sperm
Definition
Form of nuclear division that divides a diploid cell into
haploid cells; important in forming gametes (egg and
sperm) for sexual reproduction
Process by which gametes are produced through the
combination of meiosis and other maturational
changes
Male gamete
Egg
Female gamete
Traits
Characteristic that is inherited (or passed from parent
to offspring)
Genetics
Study of heredity patterns and variation of organisms
Purebred
Type of organism that whose ancestors are genetically
uniform
Cross
Mating of two organisms
Law of segregation
Mendel’s 1st law, stating that (1) organisms inherit
two copies of genes, one from each parent, and (2)
organisms donate only one copy of each gene in their
gametes because the genes separate during gamete
formation
Gene
Specific region of DNA that codes for a particular
protein
Gametogenesis
Term
Allele
definition
Any of the alternative forms of a gene that occurs at a
specific place on a chromosome
Homozygous
Characteristic of having two of the same alleles at the
same locus of sister chromatids
Heterozygous
Characteristic of having two different alleles that
appear at the same locus of sister chromatids
Genome
All of an organisms genetic material
Genotype
Collection of all of an organisms genetic information
that codes for traits
Phenotype
Collection of all of an organisms physical
characteristics
Dominant
Allele that is expressed when two different alleles are
present in an organisms genotype
Recessive
Allele that is not expressed unless two copies of it are
present in an organisms genotype
Punnett Square
Model for predicting all possible genotypes resulting
from a cross or mating
Monohybrid cross
Cross or mating, between organisms that involves
only one pair of contrasting traits
Term
Testcross
Dihybrid cross
definition
Cross between an organism with an unknown
genotype and an organism with a recessive
phenotype
Cross, or mating between organisms involving two
pairs of contrasting traits
Law of independent
assortment
Mendel’s 2nd law, stating that the allele pairs separate
from one another during gamete formation
Probability
Likelihood that a particular event will happen
Crossing over
Exchange of chromosome segments between
homologous chromosomes during meiosis I
Genetic linkage
Tendency for genes located close together on the
same chromosome to be inherited together