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104 terms

9th grade

biology semester 1
STUDY
PLAY
active trasport
the transport of materials against a concentration gradient
anaphase
phase of mitosis in which sister chromatids separate from each other
hypotonic solution
the concentration of dissolved substances is lower in the solution outside the cell than the concentration inside the cell
cell cycle
the regular sequence of growth and division that cells undergo.
inter-phase
the period in which chromosomes duplicate
gene
the segment of dna that controls the production of a protein
metaphase
the stage in mitosis or meiosis in which the duplicated chromosomes line up along the equatorial plate of the spindle
sister chromatids
two halves of the doubled chromosome structure
cancer
Uncontrolled Cell DIvision
facilitated diffusion
passive transport with the aid of transport protiens
mitosis
the process by which nuclear material is divided equally between two new cells
endocytosis
some cells surround and take in materials by this process
centriomeres
the structures that hold together sister chromatids
ionic bonding
water dissolves many ionic and molecular compounds because of this
nucleus
center of an atom
the atoms stop moving
when there is no difference in the concentration of a substance from one area to another
solution
mixture in which one or more substances are distributed evenly in another substance
metabolism
all of the chemical reactions that occur within an organism
peptide bond
Bond between amino acids
enzyme
a protein that changes the rate of a chemical reaction
polar molecule
molecule with an unequal distribution of charge
polymer
large molecule formed when many smaller molecules bond together
diffusion
the process by which molecules move from an area of higher concentration to an area of lower concentration
isotopes
atoms of the same element that have different numbers of neutrons
compounds
atoms of two or more elements chemically combined are...
covalent
two atoms that share electrons are held together by these type of bonds
sex chromosomes
23rd pair of chromosomes that differ in males and females
multiple alleles
a trait controlled by four alleles is said to have this
deoxyribose sugar and thymine
a DNA nucleotide may be made up of a phosphate group, along with
mRNA
during the process of transcription, DNA serves as the template for making_____ which leaves the nucleus and travels to the ribsomes
frameshift mutation
the addition or deletion of a single base in a DNA molecule
watson and crick
Figured out structure of DNA was a double helix
nitrogenous bases
adenine, guanine, cytosine, thymine
replication
process in which DNA makes a copy of itself
codon
each set of three nitrogenous bases representing and amino acid
tRNA
brings amino acids to the ribosomes for the assembly of protiens
point mutation
a change in a single base pair in DNA molecule
nondisjunction
failure of homologous chromosomes to separate properly during meiosis; results in gametes with too many or too few chromosomes
translation
the process of converting RNA into an amino acid sequence
chromosomal mutation
when parts of chromosomes are broken off and lost or reattached incorrectly during mitosis or meiosis
cancer
mutations in DNA can result in cells reproducing rapidly, producing the disease called
reproduction
The process by which organisms make more of their own kind from one generation to the next
control
in an experiment, the standard that is used for comparison
homeostasis
process by which organisms maintain a relatively stable internal environment
adaptation
any structure, behavior, or internal process that enable an organism to better survive in an environment
hypothesis
a testable explanation for a question or problem
parts of adenosine diphosphate
ribose, adenine, two phosphate groups
stroma
the light-independent reactions of photosynthesis take place here
reflected
leaves appear green because the green portion of the light strikes them is
photosynthesis
use light energy to change CO2 and water into O2 and carbohydrates
maintain homeostasis
requires detection and the ability to respond, an organism maintains a stable internal environment, characteristic of life
hydrogen ions
In respiration, the final electron acceptor in the electron transport chain
gyclolysis
2 molecules of ATP are used in the first step and 4 molecules of ATP are produced in the second step
light-dependent reactions release oxygen
in the process of photsynthesis
codominant alleles
cause the phenotypes of both homozygous to be produced in heterozygous individuals
completely dominant alleles
phenotypes of both heterozygous and homozygous dominant individuals have the same phenotype.
incomplete dominance
a phenotype of the heterozygote is intermediate between those phenotypes expressed by the homozygotes
carrier
a heterozygous individual
simple recessive heredity
inheritance pattern of phenylketonuria and Tay-Sachs disease
polygenic inheritance
the inheritance pattern of a trait that is controlled by two or more genes
pedigree
a graphic representation of an individual's family tree
autosomes
the other 22 pairs of chromosomes
sex-linked traits
traits controlled by genes located on the X or Y chromosome
codominant alleles
when roan cattle are mated, 25% of the offspring are red, 50% are roan, and 25% are white. Upon examination, it can be seen that the coat of a roan cow consists of both red and white hairs. This trait is controlled by
homozygous
having two identical alleles for a given trait
crossing over
the exchange of genetic material between nonsister chromatids
fertilization
The uniting of the male and female gametes
meiosis
cell division that produces gametes
nondisjunction
failure of homologous chromosomes to separate properly during meiosis
zygote
the cell produced when a male gamete fuses with a female gamete
haploid
a cell that contains one member of each chromosome pair
alleles
different forms of genes
pollination
the transfer of a male pollen grain to the pistil of a flower
egg
the gamete that contains genes contributed by the mother
homozygous
two identical alleles for a trait
haploid
(genetics) an organism or cell having only one complete set of chromosomes
heredity
Mendel's law of heredity "in meiosis, the way in which a chromosome pair separates does not affect the way other pairs separate
provide usable nitrogen for the plants
bacteria that live in the roots of legumes
binary fission
The type of cell division by which prokaryotes reproduce. Each dividing daughter cell receives a copy of the single parental chromosome.
causing holes to develop in their cell walls
penicillin kills bacteria by
cell wall
a structure outside the plasma membrane in some cells
nucleus
the functions of a eukaryotic cell are managed by this
chromatin
in a cell, the tangles of long strands of DNA form this
endoplasmic reticulum
the folded system of membranes that forms a network of interconnected compartments inside the cell
chlorophyl
pigment - gives plants a green color
cytoskeleton
network of tiny rods and filaments that forms a framework for the cell
chloroplast
found in plants the structures that capture the energy from sunlight and converts it into chemical energy
transport proteins
make up the selectively permeable membrane that controls which molecules enter and leave the cell
cilia
short projections used for oarlike locomotion
mitochondria
in a cell, the breakdown of molecules in order to release energy occurs in this
prokaryote
an organism with a cell that lacks a true nucleus
plasma membrane
the movement of the materials into and out of the cells is controlled by this
organelles
the small, membrane-bound structures inside a cell
ribosomes
site of protein synthesis
lysosomes
cell structures that contain digestive enzymes
protists
kingdom of one celled organisms with a nucleus
bacteria
single-celled organisms that lack a nucleus; prokaryotes
euglenoids
have characteristics of both autotrophs and heterotrophs. single celled algae with a flagellum- they can eat like a animal
sporophyte
the stage in the life cycle of a plant in which the plant produces spores
gametophyte
the stage in the life cycle of a plant in which the plant produces gametes, or sex cells
what is the relationship between the sporophyte and gametophyte stages of some algae?
gametes fuse to form a zygote which is the diploid form that is called sporophyte
What triggers sexual reproduction in diatoms
have two shells of silica (glass) overlapping like the halves of a petri dish (Chrysophyta) when the two halves (boxes) separate, it triggers sexual reproduction
gonyaulax catanella, produces an extremely strong nerve toxin
what causes the dangerous red tides in the ocean?
phycobolins
what adaptation helps red algae to live in deep water?