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Biology STAAR review

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carbohydrate
biomolecule made of carbon, hydrogen, and oxygen; used to make energy (ATP)
ex) starch, glucose, fructose
lipid
biomolecule that is fat; makes up the cell membrane with phospolipids, stores energy, and protects internal organs
ex) fats, oils, waxes
protein
biomolecule made up of carbon, hydrogen, oxygen, and nitrogen; made of amino acids; functions include growth, repair, and metabolic functions
ex) hemoglobin, enzymes
nucleic acids
biomolecule that stores genetic material, carry out daily functions, and make proteins in protein synthesis
ex)DNA, RNA
lysosome
organelle that carries out the digestive processes in a cell
rough ER
has ribosomes; makes proteins
smooth ER
detoxifies and makes lipids - has no attached ribosomes
golgi apparatus
sorts and distributes proteins
ribosomes
where proteins are made
binary fission
cell division the occurs in bacteria
result: 2 identical organisms (clones)
mitosis
cell division in somatic cells of multicelled organisms (nonsex cells) that occurs for growth and development
result: 2 cells with the same # of chromosomes as the parent cell
meiosis
cell division in gametes (sex cells); makes reproductive cells
result: 4 cells with half the # of chromosomes as the parent cell
plasma membrane
cell membrane composed of phospolipid molecules to serve as a boundary; semi-permeable
homeostasis
maintaining a balanced internal enviornment regarless of the external enviorment
passive transport
when substances pass across the membrane without requiring cellular energy
ex) osmosis
osmosis
the diffusion of water across a memebrane from an area of high water concentration to an area of low water concentration
active transport
when cell enegry is required for substances to pass across the plasma membrane - ATP needed
cellular respiration
the process of transferring stored energy from glucose to energy for the cell (ATP)
cellular respiration formula
C6 H12 06 + 6O2 ---> 6CO2 + 6H2O + ATP
photosynthesis
the process by which plants make their own food (glucose)
photosynthesis formula
6CO2 + 6H2O + sunlight ---> C6 H12 O6 + 6O2
virus
infectious agent that replicates only within the cells of living hosts, mainly bacteria, plants, and animals: composed of an RNA or DNA core, a protein coat, and, in more complex types, a surrounding envelope.
bacteriophage
a virus that attacks bacterial cells
DNA
deoxyribonucleic acid; found in the nucleus of cells and contains the hereditary information for making proteins; made up of nucleotides; double helix, double stranded
nucleotide
building blocks of DNA; made up of a sugar, phosphate, and a nitrogen base
DNA replication
must occur before a cell can divide
ex) GATTACACG ---> CTAATGTGC
RNA
ribonucleic acid; three types of RNA that are involved in making proteins; single stranded, sugar ribose, and RNA had Uracil instead of Thymine
mRNA
messanger RNA; a copy of the DNA code
tRNA
transfer RNA; carries the amino acids to the ribosomes to assemble proteins
rRNA
ribosomal RNA; makes up the ribosomes
codon
a sequence of 3 nucleotides of mRNA; codes for an amino acid
protein synthesis
the process by which the cell makes proteins using the DNA code - transcription and translation
transcription
the DNA code is copied to make mRNA; hydrogen bonds between the DNA seperate --> mRNA nucleotides join one side of the DNA strand to make a copy --> mRNA leaves nucleus o take the copied DNA to a ribosome
translation
tRNA brings amino acids to the ribosome to make a protein
genetics
the study of heredity
allele
alternate forms of genes; located on chromosome pairs
phenotype
physical appearance of an organism
genotype
actual gene makeup
homozygous
when both genes are the same
heterozygous
when the two genes are different
punnett square
chart used to predict the possible genotypes and phenotypes of an organism
incomplete dominance
two different genes, when paired, blend together and produce a 3rd phenotype
ex)red flower and white flower produce pink flowers
codominance
both alleles are expressed
ex)a black chicken crossed with a white chicken produces a checkered chicken
sex-linked trait
found on X chromosome, Y chromosome doesnt have a gene for the trait, males only have to inherit 1 recessive gene so they are more likely to have the condition
ex)hemophilia
multiple alleles
traits controlled by more than two alleles in a population
ex)each individual has 2 genes for blood type, bur 3 alleles exist in our population. The type A allele and type B allele are codominant. Type O is recessive. This gives us 4 blood types. (A, AB, B, O)
karyotype
a picture of an organism's chromosomes; shows if an individual has too many or too few chromosomes
nondisjunction
when chromosomes fail to seperate during meiosis and gametes receive extra or missing chromosomes
mutation
a change in the DNA of a cell; only passed to offspring if it occurs in a reproductive cell or gamete - can be beneficial
ex)mistakes in replication, mistakes in transcription, external agents(chemicals,etc.)
evolution
the theory that organisms change over time
homologous structures
structures that are similar and suggest evolution from a common ancestor
vestigal strutures
structures that have little or no function but were probably used by ancestral organisms
natural selection
a scientific theory that explains the process of evolution; states that organisms with favorable traits are more likely to survive, reproduce, and pass those traits on to their offspring
taxonomy
the science of naming and classifying organisms
kingdoms
archaebacteria, eubacteria, protista, fungi, plant, and animal
phyla
smaller groups of the 6 kingdoms: kingdom, phylum, class, order, family, genus, species
scientific name
species name of an organism that includes the genus name followed by the specific name (should be italicized or underlined)
prokaryotic
no nucleus, no membrane-bound organelles, smaller, less complex
eukaryotic
nucleus, membrane-bound organelles, larger, more complex
invertebrates
organisms with no backbone
vertebrate
organisms with a backbone
plant-like protists
algae; produces much of the Earth's oxygen and green algae is said to be the ancestors of plants
animal-like protists
protozoa; classified by how they move: flagella, no movement, and pseudopods
fungus-like protists
slime mold
mollusks
muscular foot for movement and a mantle
ex)snails,squid,etc.
arthropods
have jointed appendages, an exoskeleton, and body segments
ex) insects-flies, ant, grasshopper
echinoderms
move by tiny tube feet, have spiny skin, and live in the ocean
ex) sea star, sea cucumber, etc.
melanin
pigment that gives the skin color and helps protect it from sun damage
appendicualr skeleton
the bones of the arms and legs and the structures associated with them
villi
finger-like projections that absorb nutrients that line the small intestine; the link between the digestive system and the circulatory system
neuron
nerve cell
cerebrum
part of the brain divided in two halves. controls your conscious activites, intelligence, memory, language, muscle movement, and senses
(nervous system)
cerebellum
part of the brain that controls balance, posture, and coordination
(nervous system)
brain stem
part of the brain; made up of the medulla oblongata(controls involuntary activites like breathing and heart rate), pons, and midbrain
(nervous system)
pancreas
secretes insulin which regulates blood sugar levels (endocrine system)
pituitary
gland that secretes growth hormone
(endocrine system)
thyroid
secretes thyroxin which regulates metabolism
(endocrine system)
adrenal glands
produce hormones to prepare body for "fight or flight"
(endocrine system)
testes and ovaries
reproductive hormones
(endocrine system)
red blood cells
contain hemoglobin molecules which carry oxygen (circulatory system)
white blood cells
fight disease
(circulatory system)
platelets
cell fragments that help blood clot (circulatory system)
plasma
liquid part of blood (circulatory system)
arteries
cary blood away from the heart (circulatory system)
veins
carry blood back to the heart (circulatory system)
capillaries
tiny vessels that allow for nutrients and gas exchange (circulatory system)
atria
upper chambers of the heart (circulatory system)
ventricles
lower chambers of the heart (circulatory system)
alveoli
tiny air sacs where gases are exchanged with the bloodstream (respiratory system)
trachea
windpipe (respiratory system)
bronchial tubes
passageway from the trachea to the lungs (respiratory system)
lungs
made up of tiny air sacs calle alveoli (respiratory system)
integumentary system
skin - dermins and epidermis; first line of defense and helps maintain homeostasis
skeletal system
supports the body and protects internal organs, makes red blood cells; bones - axial and appendicular skeleton
muscular system
lines organs and allows for movement of the bones; 3 types: cardiac (heart), smooth (digestive organs), and skeletal (moves bones)
digestive system
breaks down food for nutrients to be absorbed and transported to cells by circulatory system; contains mouth, esophagus, stomach, large and small intestines, and the liver
nervous system
carries messages from the brain throughout the body; made of neurons, central nervous system (brain and spinal cord), and peripheral nervous system (carries messages from body to central nervous system)
endocrine system
produces hormones; consists of the pancreas, pituitary, thyroid, adrenal, testes and ovaries
circulatory system
delivers oxygen and nutrients to cells and picks up waste from cells; consists of heart, arteries, veins, and capillaries - blood
respiratory system
takes in oxygen to be transported to the cells by the circulatory system then releases CO2 that the circulatory system brings back; consists of mouth/nose, trachea, bronchiole tubes, and lungs; diaphragm contracts for inhalation
reproductive system
produce gametes and development of offspring; male and female reproductive systems; sperm and ovules
excretory system
filters waste from the blood; kidneys and bladder
lymphatic system
immune system; tonsils, spleen, thymus
nonvascular plants
no vessels, or vascular tissue, for transporting water and nutrients; cant grow very large
ex)mosses
vascular plants
have two main types of vascular tissue: xylem and phloem
xylem
vascular tissue that transports water
phloem
vascular tissie the transports food
abiotic factor
the nonliving parts of an organisms enviornment
ex)air currents, temperature, soil, etc.
biotic factor
the living organisms that inhabit an enviornment
autotroph
organism that makes their own food (producers)
heterotroph
organisms that feed on other organisms
herbivore
heterotroph that eats only plants
omnivore
heterotroph that eats both plants and animals
carnivore
heterotroph that eats other animals
decomposers
organisms that break down and absorb dead and decaying plants and animals
mutualism
symbiotic relationship in which both species benefit
commensalism
symbiotic relationship in which one species benefits and the other is unharmed
parasitism
symbiotic relationship in which one member benefits and the other is harmed
predation
the feeding of one organism on another
carrying capacity
the maximum number of organisms of a species that an ecosystem can support
nitrogen cycle
needed by organisms to make proteins;
bacteria-->plants-->animals-->soil
phosphorous cycle
needed for cell membrane, ATP, DNA and RNA; plants--> animals-->soil
water cycle
all living things need water to survive; evaporation-->condensation-->precipitation
carbon-oxygen cycle
need carbon and oxygen for photosynthesis, cellular respiration, and life; living things take in carbon and oxygen;when the die, it is returned to the soil