exam 4 lock in

"Sister chromatids"

"Identical copies of a chromosome, connected by a centromere, formed during DNA replication."

"Centromere"

"The region of a chromosome where sister chromatids are joined and where the spindle fibers attach during cell division."

"Cell cycle"

"The series of phases that a cell goes through from its formation to its division into daughter cells."

"Interphase"

"The phase of the cell cycle where the cell grows, duplicates its DNA, and prepares for mitosis."

"Mitosis"

"The process of cell division that results in two genetically identical daughter cells."

"Prophase"

"The first stage of mitosis where chromatin condenses into chromosomes and the mitotic spindle begins to form."

"Metaphase"

"The stage of mitosis where chromosomes align at the cell's equatorial plane."

"Anaphase"

"The stage of mitosis where sister chromatids are pulled apart to opposite poles of the cell."

"Telophase"

"The final stage of mitosis where chromosomes de-condense and the nuclear envelope re-forms."

"Mitotic spindle"

"A structure made of microtubules that segregates chromosomes during cell division."

"Cleavage furrow"

"The indentation that begins the process of cytokinesis in animal cells."

"Cell plate"

"The structure that forms during cytokinesis in plant cells, leading to the separation of the two daughter cells."

"Cell cycle checkpoints"

"Regulatory points in the cell cycle that ensure proper division and prevent errors."

"Cancer"

"A disease characterized by uncontrolled cell growth and division."

"Homologous chromosomes"

"Pairs of chromosomes that have the same structure and gene sequence, one inherited from each parent."

"Diploid"

"A cell that contains two complete sets of chromosomes, one from each parent."

"Haploid"

"A cell that contains a single set of unpaired chromosomes, typical of gametes."

"Gametes"

"Reproductive cells (sperm and eggs) that are haploid and combine during fertilization."

"Fertilization"

"The process by which a sperm cell and an egg cell combine to form a zygote."

"Meiosis"

"A type of cell division that reduces the chromosome number by half, producing four haploid cells."

"Karyotype"

"A visual representation of an individual's chromosomes, used to assess chromosomal abnormalities."

"Nondisjunction"

"The failure of homologous chromosomes or sister chromatids to separate properly during cell division."

"Phases of the cell cycle"

"G1, S, G2, and M phases."

"Cytokinesis in animals vs. plants"

"In animals, it involves the formation of a cleavage furrow; in plants, it involves the formation of a cell plate."

"Factors stopping cell growth"

"Contact inhibition, DNA damage, and lack of nutrients."

"Factors promoting cell growth"

"Growth factors, nutrients, and sufficient space."

"Checkpoints in the cell cycle"

"G1 checkpoint, G2 checkpoint, and M checkpoint that monitor the cell's readiness to proceed."

"Gamete types"

"Sperm and egg."

"Difference from somatic cells"

"Gametes are haploid and involved in reproduction, while somatic cells are diploid and make up the body."

"Meiosis I phases"

"Prophase I, Metaphase I, Anaphase I, Telophase I."

"Meiosis II phases"

"Prophase II, Metaphase II, Anaphase II, Telophase II."

"Meiosis and genetic variability"

"Meiosis introduces genetic diversity through independent assortment and crossing over."

"Crossing over"

"The exchange of genetic material between homologous chromosomes during Prophase I of meiosis."

"Genetic diversity from crossing over"

"It creates new combinations of alleles, contributing to variation in offspring."

"Nondisjunction effects"

"It can lead to conditions like Down Syndrome due to an abnormal number of chromosomes."

"Down Syndrome cause"

"It is typically caused by an extra copy of chromosome 21 due to nondisjunction during meiosis."

"Genetics"

"The study of heredity and the variation of inherited characteristics."

"True-breeding"

"Organisms that, when mated, produce offspring identical to themselves."

"Hybrid"

"Offspring resulting from the cross of two different true-breeding varieties."

"P generation"

"The parental generation in a genetic cross."

"F1 Generation"

"The first generation of offspring from a genetic cross."

"F2 Generation"

"The second generation of offspring, produced from the F1 generation."

"Alleles"

"Different versions of a gene that can exist at a specific locus."

"Homozygous"

"Having two identical alleles for a particular gene."

"Heterozygous"

"Having two different alleles for a particular gene."

"Dominant"

"An allele that expresses its phenotype even in the presence of a recessive allele."

"Recessive"

"An allele that only expresses its phenotype when homozygous."

"Genotype"

"The genetic makeup of an organism."

"Phenotype"

"The observable physical or biochemical characteristics of an organism."

"Monohybrid cross"

"A genetic cross between individuals that differ in one trait."

"Dihybrid cross"

"A genetic cross between individuals that differ in two traits."

"Incomplete dominance"

"A genetic situation where one allele does not completely dominate another."

"Codominant"

"A genetic scenario where both alleles in a heterozygote are fully expressed."

"Multiple alleles"

"More than two possible alleles exist for a particular gene."

"Sex-linked genes"

"Genes located on sex chromosomes, often affecting traits related to gender."

"Sex chromosomes"

"Chromosomes that determine the sex of an organism."

"X-linked genes"

"Genes located on the X chromosome."

"Character"

"A heritable feature that varies among individuals."

"Trait"

"A specific characteristic of an organism."

"Phenotype example"

"Brown eyes (trait) with genotype Bb."

"Punnett square"

"A diagram used to predict the outcome of a genetic cross."

"Testcross"

"A cross between an individual with an unknown genotype and a homozygous recessive individual."

"Incomplete dominance vs. complete dominance"

"Incomplete dominance results in a blend of traits, while complete dominance shows one trait over another."

"Human blood types"

"There are more than two blood types due to multiple alleles (A, B, O)."

"X-linked disorders"

"X-linked disorders affect males more because they have only one X chromosome."

"Nucleotide"

"The basic building block of DNA and RNA, consisting of a sugar, phosphate, and nitrogenous base."

"Deoxyribonucleic acid"

"The molecule that carries genetic information in living organisms."

"Sugar-phosphate backbone"

"The structural framework of nucleic acids, consisting of alternating sugar and phosphate groups."

"Helicase"

"An enzyme that unwinds the DNA double helix during replication."

"Double helix"

"The structure of DNA, consisting of two intertwined strands."

"Semiconservative model"

"The method of DNA replication where each new DNA molecule contains one old and one new strand."

"DNA polymerase"

"An enzyme that synthesizes new DNA strands by adding nucleotides."

"DNA ligase"

"An enzyme that joins Okazaki fragments on the lagging strand during DNA replication."

"Okazaki fragment"

"Short segments of DNA synthesized on the lagging strand during DNA replication."

"Transcription"

"The process of copying a segment of DNA into RNA."

"Translation"

"The process of synthesizing proteins from mRNA."

"Codon"

"A sequence of three nucleotides that corresponds to a specific amino acid."

"RNA polymerase"

"An enzyme that synthesizes RNA from a DNA template."

"Messenger RNA"

"The RNA molecule that carries genetic information from DNA to the ribosome."

"Introns"

"Non-coding segments of RNA that are removed during RNA processing."

"Exons"

"Coding segments of RNA that are expressed and translated into proteins."

"RNA processing"

"The modification of RNA before it is translated into protein."

"Transfer RNA"

"The type of RNA that brings amino acids to the ribosome during protein synthesis."

"Anticodon"

"A sequence of three nucleotides in tRNA that pairs with a complementary codon in mRNA."

"Ribosomal RNA"

"The type of RNA that makes up the major part of ribosomes."

"Mutation"

"A change in the DNA sequence that can lead to changes in phenotype."

"Structure of a nucleotide"

"A nucleotide consists of a sugar, a phosphate group, and a nitrogenous base."

"Nitrogenous bases in DNA"

"Adenine, Thymine, Cytosine, and Guanine."

"RNA"

"Ribonucleic acid, a molecule essential for various biological roles in coding, decoding, regulation, and expression of genes."

"Watson and Crick"

"Scientists who discovered the double helix structure of DNA using X-ray diffraction data and model building."

"Pairing rules"

"In DNA, adenine pairs with thymine and cytosine pairs with guanine; in RNA, adenine pairs with uracil."

"DNA replication"

"Base pairing rules allow DNA to replicate by ensuring that each strand serves as a template for a new complementary strand."

"Semiconservative model"

"The model of DNA replication where each new DNA molecule consists of one old strand and one new strand."

"Enzymes in replication"

"Key enzymes include DNA helicase (unwinds DNA), DNA polymerase (synthesizes new DNA strands), and DNA ligase (joins Okazaki fragments)."

"Leading strand"

"The DNA strand that is synthesized continuously in the same direction as the replication fork."

"Lagging strand"

"The DNA strand that is synthesized discontinuously in short segments, known as Okazaki fragments, opposite to the direction of the replication fork."

"Genetic information flow"

"The process by which genetic information is transferred from DNA to RNA to protein, known as the central dogma of molecular biology."

"Codons"

"Triplet sequences of nucleotides in mRNA that specify particular amino acids during protein synthesis."

"Transcription"

"The process of synthesizing RNA from a DNA template, involving RNA polymerase, a promoter, and a terminator."

"Transcription location"

"Transcription occurs in the nucleus of eukaryotic cells and in the cytoplasm of prokaryotic cells."