Fundamental Concepts in Cell Biology and Genetics, Exams of Nursing

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Adaptation- - correct answersThe adjustment or changes in behavior, physiology, and structure of an organism to become more suited to an environment. Aerobic- - correct answersA process that requires oxygen. Allele -An alternative form of a gene. An example would be genes that encode eye color —some encode blue eyes (one allele), while others encode brown, green, or hazel eye colors (other alleles). - correct answers amino acids - - correct answersA small organic molecule with the structure of an amino group, a carboxylic acid group, and an "R" group, which are all bonded to a single central carbon atom. The difference between the "R" group is what distinguishes one amino acid from another. Amino acids are the building blocks of proteins. Anaerobic- - correct answersA process that occurs without oxygen. Anaphase- - correct answersA stage within the mitosis phase of cell division (also known as cell reproduction). Anaphase starts when sister chromatids separate from each other and ends when each set of separated, sister chromatids arrives at the opposite poles of the cell. anaphase I- - correct answersThe third stage of Meiosis I—the two homologous chromosomes separate and migrate toward opposite poles. anaphase II- - correct answersThe third stage in Meiosis II—the centromeres separate and the sister chromatids (now individual chromosomes) move toward the opposite poles of the cell. artificial selection- - correct answersDeliberate mating between two individuals who were selected based on desired traits. asexual reproduction - - correct answersA type of reproduction where genetically identical offspring are created from a single parent. This type of reproduction does not utilize meiosis or gametes. Bacteria and fungi are examples of organisms that reproduce in this manner. - correct answers Atom- - correct answersThe basic unit of matter that cannot be further

broken down without losing its unique properties. One atom consists of a dense nucleus surrounded by a cloud of electrons. Autosomal- - correct answersDescribes a trait associated with alleles located on autosomes (non sex chromosomes).

autosomal chromosome- - correct answersA chromosome not involved in sex determination. biogeochemical cycle- - correct answersThe processes that transfer chemical elements between biotic and abiotic components in an ecosystem. There are several main cycles: the water cycle, the carbon cycle, the nitrogen cycle, and the phosphorus cycle. Biome- - correct answersA large naturally occurring community of plants and animals occupying a major habitat. Examples include tropical forest and arctic tundra. Biomes- - correct answersA pattern of distribution of ecosystems across the globe, where similar environmental conditions lead to similar animal and plant adaptations. Examples of biomes include tropical rainforests, deserts, and tundra. biosphere- - correct answersAll areas on, within, and around the planet Earth that are capable of supporting life. Calvin cycle (Calvin-Ben - correct answersson cycle or light-independent reaction)- The set of chemical reactions that take place in chloroplasts during photosynthesis. The cycle is light-independent because it takes place after the energy has been captured from sunlight. Also called Calvin- Benson Cycle, Benson-Calvin Cycle. Carbohydrates- - correct answersThe extracellular surface of the cell membrane is decorated with carbohydrate groups attached to lipids and proteins. These short carbohydrates play a role in giving a cell its identity (i.e., distinguishing self from non- self) and are the distinguishing factor in human blood types. carbon cycle- - correct answersThe biogeochemical cycle through which carbon flows between the atmosphere, water, land, and ecosystems. cell cycle- - correct answersA series of phases in the life of the cell through which it grows and divides. cell wall- - correct answersProtective and reinforcing structure found in certain cells, situated outside the plasma membrane. Bacterial cell walls are mainly built of peptidoglycan, although they may also contain lipidic molecules. Among eukaryotes, plants and fungi possess cell walls, made of cellulose and chitin, respectively. cellular respiration- - correct answersUse of oxygen to release energy from nutrients; also called aerobic respiration.

Centromere- - correct answersA specific section of a chromosome where spindle fibers attach during cell division; also the connection point of sister chromatids.

Chlorophyll- - correct answersA plant pigment used to absorb light energy for photosynthesis. Chlorophyll gives plants their green color because it absorbs red and blue light particularly well, while reflecting green. Chloroplast- - correct answersAn organelle found in plants and photosynthetic protists (single-celled eukaryotic organisms) that contain pigments such as chlorophyl. Its primary function is to capture solar energy and convert it into chemical energy through the process of photosynthesis. Chloroplast absorbs sunlight energy and uses the energy to power the synthesis of organic food molecules (sugars). A chloroplast contains its own DNA as a single circular chromosome. Sister Chromatid - - correct answersOne of two identical copies of a chromosome duplicated during the S phase of the cell cycle. A centromere connects two sister chromatids together. When joined together, sister chromatids compose one chromosome. Chromatids are separated from each other during mitosis or meiosis II. Citric acid cycle- - correct answersThe 2nd stage of aerobic cellular respiration that occurs when acetyl CoA combines with a four-carbon molecule and goes through a cycle of reactions, ultimately producing ATP, NADH, FADH2, and CO2. climate change- - correct answersIt is the full range of climatic disruptions that have occurred as a probable result of human alteration of the atmosphere. In other words, it is recent climate warming—and weirdness— that is probably caused by human activities and technology use. Codominance- - correct answersA form of dominance where both alleles of a gene pair in a heterozygote are fully expressed. This results in offspring with a phenotype that is neither dominant nor recessive. A typical example showing codominance is the ABO blood group system. Codons- - correct answersA sequence of three nucleotides in an mRNA molecule that specifies which amino acid should be added to a growing polypeptide chain. Commensalism- - correct answersA symbiotic relationship in which one species benefits and the other does not, but also is not harmed. Competition- - correct answersA type of interspecific interaction where both species are harmed. complementary base pairing- - correct answersDescribes the hydrogen bonding that occurs between specific nucleotides on opposing strands of DNA or RNA. In DNA, adenine is paired with thymine, and guanine is paired with cytosine. When RNA is made from DNA, adenine is paired with uracil,

and guanine is paired with cytosine.

Consumers- - correct answersAn organism that must eat or absorb complex food molecules derived from the bodies of other organisms. Consumers get their energy and nutrients from such food molecules. Humans and other animals are consumers, as are fungi and most bacteria. covalent bonds- - correct answersCovalent bonds represent the sharing of the electrons (negatively charged subatomic particles between atoms). The number of covalent bonds that can form is dictated by the number of unpaired electrons in the outer valence shell of the atom. Cytoplasm- - correct answersThe substance that fills the inside contents of a cell between the plasma membrane and the nucleus. Contains a semifluid medium, composed mainly of water, and organelles (organelles are present only if it is a eukaryotic cell). Cytoskeleton- - correct answersA eukaryotic cell structure formed by a series of protein filaments. The cytoskeleton is a scaffold for the cell structure and a framework for many cellular activities, including movement and cell division. Decomposer- - correct answersBacteria and fungi that colonize dead material and absorb food molecules from it. deoxyribonucleic acid (DNA)- - correct answersA nucleic acid polymer that contains the genetic instructions for all living organisms. DNA is composed of two strands of nucleotides that are intertwined in a double helix. Detritivores- - correct answersAnimals that feed on dead organic matter. Some detritivores specialize on eating dead animals (e.g., vultures) and others feed on dead plant material (e.g., earthworms). Disaccharide- - correct answersA carbohydrate made of two monosaccharides linked together by a covalent bond. Two common disaccharides are sucrose and lactose. glucose + fructose = Sucrose (table sugar) glucose + galactose = Lactose (milk sugar) DNA: deoxyribonucleic acid- - correct answersThe nucleic acid that contains genetic instructions for making RNA and, ultimately, proteins in all living organisms. DNA is composed of two strands of nucleotides, which are intertwined in a double helix. Ecology- - correct answersThe branch of biology that deals with the relations of organisms to one another and to their physical surroundings. ecosystem diversity- - correct answersThe variety of distinct ecosystem types (habitats) within a region. In some places a wide array of habitats can form a diverse patchwork of life.

electron transport chain- - correct answersThe last stage of aerobic cellular respiration where the NADH and FADH2 made in other steps deposit their electrons. As electrons move down the chain, energy is released and used to move protons across the mitochondrial membrane to form ATP. At the end of this process, oxygen acts as the final electron acceptor to form water. Electronegativity- - correct answersThe tendancy of an atom to hold shared electrons more close to its nucleus. Atoms like oxygen have a high electronegativity. This means when oxygen forms a covalent bond with an atom of lower electronegativity, the shared electrons will stay closer to the oxygen atom than to the other atom. Strongly electronegative atoms bonded to weakly electronegative hydrogen atoms, in a molecule, result in hydrogen bonding. The most important strongly electronegative elements in biological systems are oxygen and nitrogen. Electrons - - correct answersNegatively charged subatomic particle that occupies shells surrounding the nucleus and has a mass that is so small it is considered to be zero. Endocytosis- - correct answersThe movement of materials into the cytoplasm of a cell via vesicles or vacuoles. endoplasmic reticulum (ER)- - correct answersAn organelle made up of a series of sacs and tubes that assemble other cellular components. There are two types of endoplasmic reticulum: rough and smooth. Rough ER has ribosomes embedded in it and plays an important role in protein synthesis. Smooth ER, which does not have ribosomes, has different functions such as the synthesis of lipids. eukaryotic cells- - correct answersA type of cell that has a membrane- enclosed nucleus and other membrane-enclosed structures (called organelles) such as mitochondria, chloroplasts, cytoskeleton, and the Golgi apparatus. All organisms except bacteria and archaea are composed of eukaryotic cells (also referred to as eukaryotes); that is, all species of animal, plants, and fungi are composed of eukaryotic cells. Exocytosis- - correct answersThe movement of materials out of the cytoplasm of a cell via membranous vesicles or vacuoles. FADH2- - correct answersOne of the electron carrier molecules produced in the Krebs cycle of aerobic cellular respiration. It is transferred to the electron transport chain where the electrons are used to generate ATP. Fats- - correct answersA type of lipid composed of glycerol and saturated fatty acids; typically solid at room temperature.

Fermentation- - correct answersFermentation breaks down organic molecules and stores energy as ATP. Fermentation reactions do not require oxygen, and they do not break down all glucose fully to carbon dioxide. Instead, they end with organic molecules that still contain considerable chemical potential energy. Such pathways produce only a tiny amount of ATP compared to aerobic cellular respiration. Fermentation can produce a variety of end products including lactic acid, ethanol, and others. Fitness- - correct answersA measure of reproductive success in organisms. If an individual has high fitness, it has been able to reproduce and pass on its traits to its offspring. Flagella: Flagellum (plural flagella) - - correct answersA long whip-like projection used in moving the cell from one place to another. It can be found in both prokaryotes and eukaryotes. A cell may have one or more flagella. fossil record- - correct answersThe total number of fossils that have been discovered, as well as to the information derived from them. foundation species- - correct answersA species that are physically dominant (largest and/or most abundant) in communities. G1- - correct answersThe first growth phase of Interphase in the cell cycle when the cells increase in size and make proteins and organelles needed for normal cellular functions. G2- - correct answersThe 2nd growth phase of Interphase in the cell cycle where the DNA and the cell is checked to ensure it is ready to undergo cell division. Gamete- - correct answersA haploid, sex cell (egg or sperm) produced from germ cells that have undergone meiosis. When two gametes join in fertilization, the resulting zygote is a complete diploid cell. gene flow- - correct answersThe result of fertile members of a species moving into or out of a population. genetic diversity- - correct answersDiversity in a population due to many different genetic traits being present. A population with high amounts of allele variety has high genetic diversity. genetic drift- - correct answersThe change in a gene pool as a result of random chance. Glucose- - correct answersA simple carbohydrate (monosaccharide) with the chemical formula of C6H12O6. This is the primary product (output) of photosynthesis and the primary reactant (input) of cellular respiration.

Glycolysis- - correct answersThe breakdown of glucose into pyruvate. Occurs in the cytoplasm of cells and produces small amounts of the energy molecule ATP and the electron carrier molecule NADH. Haploid- - correct answersCells that contain only one set of chromosomes. Haploid cells are referred to as "1n." Gametes (sperm and eggs) are haploid. In human haploid gametes contain 23 chromosomes. Histones- - correct answersSmall proteins found along the length of chromosomes that can move closer or farther apart to help chromosomes contract into chromatin during cell division or decondense after cell division is complete. homologous chromosomes- - correct answersChromosome pairs (one from each parent) that are similar in length, gene position, and centromere location. The position of the genes on each homologous chromosome is the same, however, the genes may contain different alleles. hydrogen bonds- - correct answersHydrogen bond (H-bond) is an interaction between a partially positive hydrogen atom and a partially negative atom with an unshared (lone) pair of electrons. In order for hydrogen to have a sufficient partial positive charge, hydrogen must be covalently attached to a very electronegative atom (O, N, P). A partially negative atom with a lone pair of electrons must also be a highly electronegative atom like oxygen or nitrogen. hydrophilic. - - correct answersSubstances that dissolve in, or are attracted to, water. Hydrophilic (from Greek meaning "water-loving") refers to molecules that are water soluble. Hydrophilic molecules contain polar functional groups that can form hydrogen bonds or ionic bonds with water. Ionic and polar substances are hydrophilic. hydrophobic.- - correct answersHydrophobic (from Greek meaning "water- fearing") refers to molecules that do not interact with water and are characterized by a complete lack of electronegative atoms. In aqueous solutions, the hydrophobic molecules are driven together to the exclusion of water. incomplete dominance- - correct answersA form of intermediate inheritance where one allele for a specific trait is not completely expressed over the other allele in the heterozygote. This results in a third phenotype where the expressed physical trait is a combination of the phenotypes of both alleles. inorganic molecules- - correct answersSimple molecules not found in living things. They may contain carbon or hydrogen, but not both. Examples include CO2, N2, O2.

Interphase- - correct answersThe stage of the cell cycle when division (mitosis) does not occur. During interphase, the cell grows, acquires nutrients, and replicates both its chromosomes as well as its organelles. Interphase consists of the G1 (chromosomes condense), S (DNA duplicates), and G2 (DNA integrity checked and repaired) phases of the cell cycle. Cells spend the majority of their time in interphase. interspecific interaction- - correct answersAn effect of one population on another in a community; any interaction between members of different species. This is a type of community interaction and has three subtypes: mutualism, predation, and competition. ionic bonds- - correct answersAn attractive force generated by the interactions between ions of opposite charges. An ionic bond forms due to an attraction between a positive and a negative ion. No electron sharing occurs in the ionic bond. In the formation of an ionic bond, electrons are said to be transferred from one atom to another. keystone species- - correct answersA species that has an unexpectedly strong effect on the stability or diversity of a community that is much larger than its abundance or biomass would suggest. Krebs cycle (citric acid cycle)- - correct answersThe 2nd stage of aerobic cellular respiration that occurs when acetyl CoA combines with a four- carbon molecule and goes through a cycle of reactions, ultimately producing ATP, NADH, FADH2, and CO2. law of segregation:- - correct answersStates that the two alleles for each gene separate from each other when gametes form, so that each gamete contains one allele of each gene. light-dependent reaction- - correct answersThe first stage of photosynthesis where light energy is used by the chlorphyll to generate chemical energy in the form of ATP and electron carrier molecules in the form of NADPH. light-independent reaction- - correct answersAlso called Calvin-Benson Cycle or Benson-Calvin Cycle. The set of chemical reactions that take place in chloroplasts during photosynthesis. The cycle is light-independent because it takes place after the energy has been captured from sunlight. Lipids- - correct answersOrganic marcromolecules that are largely nonpolar (electrons are evenly distributed among atoms in a molecule) and as a result are hydrophobic ("water-fearing"). Lipids perform many functions in the cell including storage of energy for long-term use in the form of fats, insulation from the environment, and building blocks for hormones. Lipids include fats, oils, waxes, phospholipids, and steroids.

Macroevolution- - correct answersA change in a biological lineage including the origin or extinction of species. This is evolution beyond the species level.

Macromolecules - - correct answersA large and complex molecule formed by combining smaller subunits producing a larger unit consisting of many atoms with new properties. Biological macromolecules are special large macromolecules produced by living organisms that contain carbon atoms covalently bonded to hydrogen atoms. There are four main types of biological macromolecules (sometimes referred to as biomolecules or biomacromolecules) that you will be learning about in this course: carbohydrates, nucleic acids, lipids, and proteins. Meiosis - - correct answersA type of cell division in which a single, diploid germ cell is divided into four, haploid gamete cells. Meiosis only occurs in organisms that sexually reproduce and results in the production of sperm in males and eggs in females. meiosis I- - correct answersThe first half of the whole process of meiosis. Homologous pairs of chromosomes bind together and exchange pieces in a process called "crossing over." By the end of meiosis I, the homologous pairs of chromosomes have been sorted into separate cells. meiosis II- - correct answersThe second half of the whole process of meiosis in which the sister chromatids in each of the two haploid cells produced during meiosis I are separated. Meiosis II results in the production of four haploid gamate cells and is similar in process to mitosis. messenger RNA (mRNA)- - correct answersThe type of RNA molecules that contain instructions for making a protein. Metaphase- - correct answersThis is a stage of mitosis where the sister chromatids connected by centromeres are lined up along the plane of the cell's center (called the metaphase plate). metaphase I- - correct answersThe second stage of Meiosis I—the pairs of homologous chromosomes line up along the equator of the cell and are attached to the fully formed meiotic spindle. metaphase II- - correct answersThe second stage in Meiosis II—the chromosomes line up on the equator of the cell (similar to mitosis) and are attached to the fully formed spindle. Microevolution- - correct answersOccurs when the type or frequency of the alleles and genotypes in a population change over one to many generations of time. Mitochondria: Mitochondrion (pl. mitochondria) - - correct answersThe powerhouse of the eukaryotic cell; an organelle whose primary function is to perform cellular respiration: the process that converts chemical energy

into adenosine triphosphate

(ATP), a form that can be used directly by the cell. This organelle is surrounded by a double membrane and is where most of the cell's ATP is made. The mitochondrion is also bacteria-like, so it contains its own DNA as a singular circular chromosome. Monosaccharide- - correct answersA simple sugar (carbohydrate) containing carbon, hydrogen, and oxygen atoms in a 1:2:1 ratio respectively. Some common monosaccharides are glucose, fructose, and ribose. Mutations- - correct answersChanges to the DNA nucleotide sequence. A permanent, irreversible, and heritable change in DNA. Mutualism- - correct answersA type of interspecific interaction where both species benefit. NADH- - correct answersAn electron carrier molecule produced in glycolysis and the Krebs cycle. It is transferred to the electron transport chain where the electrons are used to generate ATP. NADPH- - correct answersAn electron carrier molecule produced in the light- dependent reactions of photosynthesis. It is transferred to the Calvin Cycle where the electrons are used to generate glucose. natural selection- - correct answersA process by which nature (i.e., the environment and all of its components) impacts the evolution of a population. Neutrons- - correct answersSubatomic particle with a neutral charge that is contained in the nucleus and has a mass of approximately 1 atomic mass unit. nitrogen cycle- - correct answersThe biogeochemical cycle through which nitrogen moves through terrestrial ecosystems. Bacteria play multiple roles in the nitrogen cycle, including nitrogen fixation and decomposition. nonrenewable resource- - correct answersResources that are in a limited supply in the earth and typically take millions of years to produce. Examples include fossil fuels, minerals, and metals. nuclear envelope- - correct answersThe double-layered membrane surrounding the nucleus of a cell. It is also called the nuclear membrane. Nucleic acids - - correct answersOrganic macromolecules, built from nucleotides, that carry out two main functions in the cell: storage of genetic information and synthesis of proteins. DNA and RNA are both nucleic acids.

nucleoid region Nucleoid - - correct answersA specific region in the cytoplasm of a prokaryotic cell where genetic material (DNA) is stored. Oils - - correct answersA type of lipid composed of glycerol and unsaturated fatty acids; typically liquid at room temperature. Organisms- - correct answersAn organism is an individual living entity that survives and reproduces as a unit. Examples include a single bacterial cell, a plant grown from a single seed, or you—as an individual human being. Organisms include any type of life form, such as animal, plant, fungus, bacteria, protist, or single-celled entity. Organs- - correct answersA collection of tissues grouped together based on a common general function. Some common organs in the human body are the heart, lungs, and kidneys. Osmosis- - correct answersThe diffusion of water across a selectively permeable membrane. Parasitism- - correct answersA symbiotic relationship between species, where one organism, the parasite, lives on or in another organism, the host, causing it harm. Phenotypes - - correct answersPhysical or physiological characteristic present; also defined as the manifestation of the genes in an organism. phospholipid bilayer - - correct answersA double layer of phospholipid molecules (each molecule consisting of a glycerol bonded to a phosphate group and two fatty acids) that is the primary component of all cellular membranes. Photosynthesis - - correct answersA metabolic pathway that uses light energy to build carbohydrates from CO2. The overall equation for photosynthesis is: CO2 + H20 + light → sugar + O2 - correct answers phylogenetic trees - correct answers- Phylogenetic tree (also called phylogeny) is a tree diagram that represents a hypothesis as to how a biological lineage may have branched and formed clades over time. Remember that as a hypothesis, phylogenetic trees are subject to change as more data are gathered and as analysis techniques improve. polygenic inheritance - - correct answersThis occurs when one phenotype is controlled by two or more genes. Examples of human polygenic inheritance are height, skin color, eye color, and weight.

Polysaccharide- - correct answersA carbohydrate (e.g., starch, cellulose, or glycogen) that consists of long chains of monosaccharides bonded together. Often used for energy storage and structural support by organisms. Predation- - correct answersA type of interspecific interaction where one species (predator) kills and eats the other species (prey). primary consumers- - correct answersOrganisms that consume or feeds on plants. Often used in terms of a specific trophic level. These organisms are herbivores. Producer- - correct answersOrganisms that make simple organic food molecules from inorganic raw materials using light energy from the sun and do not consume other living organisms to obtain nutrients. Producers make up trophic level 1 in most ecosystems. Plants, algae, and cyanobacteria are examples of producers. prokaryotic cell- - correct answersA type of cell (also called prokaryotes) lacking a nucleus and other membrane-bound organelles. Prokaryotic cells are unicellular organisms found only in the domains bacteria and archaea. prophase I- - correct answersThe first stage in Meiosis I—chromosomes condense and become visible, crossing-over occurs, the nucleolus disappears, the meiotic spindle forms, and the nuclear envelope disappears. prophase II- - correct answersThe first stage in Meiosis II—the nuclear envelope breaks down and the spindle apparatus forms. protein folding- - correct answersThe final 3-dimensional shape of proteins that results from interactions between the amino acids in the protein. Proton- - correct answersA positively charged subatomic particle that is contained in the nucleus and has a mass of approximately 1 atomic mass unit. renewal resources- - correct answersMaterial used or consumed by humans that can be replenished sufficiently to prevent complete consumption of that material. Resources are renewed through growth or other ongoing processes. Replication: Origin of Replication - - correct answersA sequence of DNA that serves as a binding site for proteins involved in initiating DNA replication. ribonucleic acid (RNA)- - correct answersThe nucleic acid composed of nucleotides in a single strand whose primary function is protein synthesis.

ribosomal RNA (rRNA)- - correct answersThe type of RNA that is a component of a ribosome, and which assists with the process of translating the instructions for making proteins that are present in messenger RNA (mRNA). s phase- - correct answersThis is the second phase of Interphase in the cell cycle where the DNA undergoes replication in preparation for cell division. Scientific inquiry- - correct answersThe application of scientific observation, experimentation, and the scientific method to study, interpret, and predict natural phenomena in the world around us. secondary consumers- - correct answersOrganisms that consume or feed on primary consumers. Often used in terms of a specific trophic level. These organisms can be either carnivores or omnivores. selectively permeable- - correct answersA selectively permeable membrane allows certain molecules or ions to pass through it by means of active or passive transport. semiconservative replication- - correct answersReplication of DNA that produces two copies that each contain one of the original strands and one newly synthesized strand. sex chromosomes- - correct answersA chromosome that is involved in sex determination. Examples include the X and Y chromosomes in humans. sex-linked- - correct answersDescribes a trait associated to alleles located on sex chromosomes, most commonly it is X-linked. sexual reproduction- - correct answersA more complicated form of reproduction where two haploid, gametes (sperm and egg) fuse to create a diploid zygote. This type of reproduction produces offspring that are genetically different from their parents. sexual selection- - correct answersNatural selection arising through preference by one sex for certain characteristics in individuals of the other sex. simple diffusion- - correct answersThe spontaneous movement of particles of any kind down a concentration gradient; that is, movement of particles from where they are more concentrated to where they are less concentrated. sister chromatid- - correct answersOne of two identical copies of a chromosome duplicated during the S phase of the cell cycle. A centromere connects two sister chromatids together. When joined together, sister chromatids compose one chromosome, and chromatids are separated from each other during mitosis or meiosis.

Speciation- - correct answersSpeciation is the formation of new biological lineage as one species splits into two or more species. speciation event- - correct answersWhen an existing species splits or branches into two or more new species that evolve independently of each other. Species- - correct answersA group of organisms whose members can and will breed with each other to produce fertile offspring. Steroids- - correct answersA type of lipid composed of a common carbon ring structure. Examples include testosterone and cholesterol. Sustainable technologies- - correct answersSolutions that meet human economic and social needs while preserving the productivity or biodiversity of ecosystems over a long period of time. Symbiosis- - correct answersA type of direct community interaction between pairs of species that are intimately and physically connected, with a smaller species (symbiont) living in or on the body of a larger species (host). These direct interactions are described using the term symbiosis, which translates to "together living." Synthesis- - correct answersProtein Synthesis. The process of producing protein chains (polypeptides) by linking together relatively simple amino acid monomers. synthesis (S)- - correct answersThis is the second phase of Interphase in the cell cycle where the DNA undergoes replication in preparation for cell division. Telophase- - correct answersThis is the final stage of mitosis. In telophase, new nuclear envelopes form around the separated chromosomes at each pole of the cell, the chromosomes unfold back into chromatin, nucleoli reappear, and the cell continues to elongate. telophase I- - correct answersThe final stage of Meiosis I—the homologous chromosome pairs reach the poles of the cell, nuclear envelopes form around them, and cytokinesis produces two separate cells. telophase II- - correct answersThe final stage of Meiosis II—nuclear envelope forms around each set of chromosomes and cytokinesis occurs, producing four daughter cells, each with a haploid set of chromosomes. template strand- - correct answersThe DNA strand used by DNA polymerase or RNA polymerase to attach complementary bases during DNA replication or RNA transcription.

Transcription- - correct answersReading the DNA and encoding an mRNA molecule with information to be taken to protein-synthesizing regions of the cell. transfer RNA (tRNA)- - correct answersThe type of RNA, directly involved in protein synthesis, that transports amino acids to ribosomes to be incorporated into an emerging protein. Translation- - correct answersSynthesis of a polypeptide from the information in an RNA sequence. trophic level - - correct answersGroupings of species in a community based on their feeding relationships. These food-based groupings are called trophic levels. Trophic level 1 is composed of producers that form the base of all ecosystems. Organisms in level 1 are eaten by organisms in level 2; organisms in level 2 are eaten by organisms in level 3; organisms in level 3 are eaten by organisms in level 4, and so on. trophic levels- - correct answersAny of the sequential stages in a food chain, occupied by producers at the bottom and in turn by primary, secondary, and tertiary consumers. Decomposers (detritivores) are sometimes considered to occupy their own trophic level. Vacuole- - correct answersA type of vesicle containing mostly water that is found in the cytoplasm of eukaryotic cells. Vacuoles are specialized mainly for storage. Their membranes do not fuse with the membranes of other cellular components. Vesicle- - correct answersA membranous sac in the cytoplasm of eukaryotic cells used to isolate and transport materials in a cell. water cycle- - correct answersThe biogeochemical cycle through which water moves between the oceans, atmosphere, glaciers, soil, and fresh water. Waxes- - correct answersNonpolar lipids that form protective layers on plants and animals. Waxes are the simplest lipids in nature, consisting of two long hydrocarbon chains linked in the middle by an ester group. Vocabulary Bio - correct answers acetyl coA - - correct answersA two-carbon molecule that is an intermediate product between glycolysis and the Krebs cycle in cellular respiration. Pyruvate from glycolysis is broken down into acetyl coA, which enters the Krebs cycle and is further broken down. Adaptation- - correct answersThe adjustment or changes in behavior, physiology, and structure of an organism to become more suited to an

environment.

Aerobic- - correct answersA process that requires oxygen. Allele - - correct answersAn alternative form of a gene. An example would be genes that encode eye color—some encode blue eyes (one allele), while others encode brown, green, or hazel eye colors (other alleles). amino acids - - correct answersA small organic molecule with the structure of an amino group, a carboxylic acid group, and an "R" group, which are all bonded to a single central carbon atom. The difference between the "R" group is what distinguishes one amino acid from another. Amino acids are the building blocks of proteins. Anaerobic- - correct answersA process that occurs without oxygen. Anaphase- - correct answersA stage within the mitosis phase of cell division (also known as cell reproduction). Anaphase starts when sister chromatids separate from each other and ends when each set of separated, sister chromatids arrives at the opposite poles of the cell. anaphase I- - correct answersThe third stage of Meiosis I—the two homologous chromosomes separate and migrate toward opposite poles. anaphase II- - correct answersThe third stage in Meiosis II—the centromeres separate and the sister chromatids (now individual chromosomes) move toward the opposite poles of the cell. artificial selection- - correct answersDeliberate mating between two individuals who were selected based on desired traits. asexual reproduction - - correct answersA type of reproduction where genetically identical offspring are created from a single parent. This type of reproduction does not utilize meiosis or gametes. Bacteria and fungi are examples of organisms that reproduce in this manner. Atom- - correct answersThe basic unit of matter that cannot be further broken down without losing its unique properties. One atom consists of a dense nucleus surrounded by a cloud of electrons. Autosomal- - correct answersDescribes a trait associated with alleles located on autosomes (non sex chromosomes). autosomal chromosome- - correct answersA chromosome not involved in sex determination.

biogeochemical cycle- - correct answersThe processes that transfer chemical elements between biotic and abiotic components in an ecosystem. There are several main cycles: the water cycle, the carbon cycle, the nitrogen cycle, and the phosphorus cycle. Biome- - correct answersA large naturally occurring community of plants and animals occupying a major habitat. Examples include tropical forest and arctic tundra. Biomes- - correct answersA pattern of distribution of ecosystems across the globe, where similar environmental conditions lead to similar animal and plant adaptations. Examples of biomes include tropical rainforests, deserts, and tundra. biosphere- - correct answersAll areas on, within, and around the planet Earth that are capable of supporting life. Calvin cycle (Calvin-Benson cycle or light-independent reaction)- - correct answersThe set of chemical reactions that take place in chloroplasts during photosynthesis. The cycle is light-independent because it takes place after the energy has been captured from sunlight. Also called Calvin-Benson Cycle, Benson-Calvin Cycle. Carbohydrates- - correct answersThe extracellular surface of the cell membrane is decorated with carbohydrate groups attached to lipids and proteins. These short carbohydrates play a role in giving a cell its identity (i.e., distinguishing self from non- self) and are the distinguishing factor in human blood types. carbon cycle- - correct answersThe biogeochemical cycle through which carbon flows between the atmosphere, water, land, and ecosystems. cell cycle- - correct answersA series of phases in the life of the cell through which it grows and divides. cell wall- - correct answersProtective and reinforcing structure found in certain cells, situated outside the plasma membrane. Bacterial cell walls are mainly built of peptidoglycan, although they may also contain lipidic molecules. Among eukaryotes, plants and fungi possess cell walls, made of cellulose and chitin, respectively. cellular respiration- - correct answersUse of oxygen to release energy from nutrients; also called aerobic respiration. Centromere- - correct answersA specific section of a chromosome where spindle fibers attach during cell division; also the connection point of sister chromatids.

Chlorophyll- - correct answersA plant pigment used to absorb light energy for photosynthesis. Chlorophyll gives plants their green color because it absorbs red and blue light particularly well, while reflecting green.

Chloroplast- - correct answersAn organelle found in plants and photosynthetic protists (single-celled eukaryotic organisms) that contain pigments such as chlorophyl. Its primary function is to capture solar energy and convert it into chemical energy through the process of photosynthesis. Chloroplast absorbs sunlight energy and uses the energy to power the synthesis of organic food molecules (sugars). A chloroplast contains its own DNA as a single circular chromosome. chromatid - correct answers Sister Chromatid - - correct answersOne of two identical copies of a chromosome duplicated during the S phase of the cell cycle. A centromere connects two sister chromatids together. When joined together, sister chromatids compose one chromosome. Chromatids are separated from each other during mitosis or meiosis II. Citric acid cycle- - correct answersThe 2nd stage of aerobic cellular respiration that occurs when acetyl CoA combines with a four-carbon molecule and goes through a cycle of reactions, ultimately producing ATP, NADH, FADH2, and CO2. climate change- - correct answersIt is the full range of climatic disruptions that have occurred as a probable result of human alteration of the atmosphere. In other words, it is recent climate warming—and weirdness— that is probably caused by human activities and technology use. Codominance- - correct answersA form of dominance where both alleles of a gene pair in a heterozygote are fully expressed. This results in offspring with a phenotype that is neither dominant nor recessive. A typical example showing codominance is the ABO blood group system. Codons- - correct answersA sequence of three nucleotides in an mRNA molecule that specifies which amino acid should be added to a growing polypeptide chain. Commensalism- - correct answersA symbiotic relationship in which one species benefits and the other does not, but also is not harmed. Competition- - correct answersA type of interspecific interaction where both species are harmed. complementary base pairing- - correct answersDescribes the hydrogen bonding that occurs between specific nucleotides on opposing strands of DNA or RNA. In DNA, adenine is paired with thymine, and guanine is paired with cytosine. When RNA is made from DNA, adenine is paired with uracil, and guanine is paired with cytosine.