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17 Cards in this Set
- Front
- Back
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Homozygous
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A person that carries two copies of the same allele at a give locus.
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HETROZYGOUS
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Heterozygous A person that carries two different alleles at a given locus
-Definition: Having two different alleles for a single trait. For example, the gene for seed shape in pea plants exists in two forms, one form or allele for round seed shape (R) and the other for wrinkled seed shape (r). A heterozygous plant would contain the following alleles for seed shape: (Rr). -ALLE, Related Terms • Genes • Heterozygous • Homozygous Definition: An alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome. For example, the gene for seed shape in pea plants exists in two forms, one form or allele for round seed shape (R) and the other for wrinkled seed shape (r). Organisms have two alleles for each trait. When the alleles of a pair are heterozygous, one is dominant and the other is recessive. The dominant allele is expressed and the recessive allele is masked. Using the previous example, round seed shape (R) is dominant and wrinkled seed shape (r) is recessive. Round: (RR) or (Rr), Wrinkled: (rr). |
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GENOTYPE
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Genotype (1) Genetic constitution of an individual.
(2) Specific alleles present at specific loci. |
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LAW OF SEGREGATION
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How are traits passed from parents to offspring? The answer is by gene transmission. Genes are located on chromosomes and consist of DNA. They are passed from parents to their offspring through reproduction. The principles that govern heredity were discovered by a monk named Gregor Mendel in the 1860's. One of these principles is now called Mendel's law of segregation.
Mendel worked with pea plants and selected seven traits to study that each occurred in two different forms. For instance, one trait he studied was pod color. Some pea plants have green pods and others have yellow pods. Since pea plants are capable of self fertilization, Mendel was able to produce true-breeding plants. A true-breeding yellow-pod plant for example would only produce yellow-pod offspring. Mendel then began to experiment to find out what would happen if he cross-pollinated a true-breeding yellow pod plant with a true-breeding green pod plant. He referred to the two parental plants as the parental generation (P generation) and the resulting offspring were called the first filial or F1 generation. |
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Mitosis
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Mitosis is the process in which a cell duplicates its chromosomes to generate two identical nuclei. It is generally followed by cytokinesis which divides the cytoplasm and cell membrane. This results in two identical cells with an equal distribution of organelles and other cellular components. Mitosis and cytokinesis jointly define the mitotic (M) phase of the cell cycle, the division of the mother cell into two sister cells, each with the genetic equivalent of the parent cell. Mitosis occurs most often in eukaryotic cells.
In multicellular organisms, the somatic cells undergo mitosis, while germ cells — cells destined to become sperm in males or ova in females — divide by a related process called meiosis. Prokaryotic cells, which lack a nucleus, divide by a process called binary fission. |
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Miosis
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In biology, meiosis (IPA: /maɪˈəʊsɪs/) is the process by which one diploid eukaryotic cell divides to generate four haploid cells often called gametes. The word "meiosis" comes from the Greek meioun, meaning "to make smaller," since it results in a reduction in chromosome number in the gamete cell. Among fungi, spores in which the haploid nuclei are at first disseminated are called meiospores, or more specifically, ascospores in asci (Ascomycota) and basidospores on basidia (Basidiomycota).
Meiosis is essential for sexual reproduction and therefore occurs in all eukaryotes (including single-celled organisms) that reproduce sexually. A few eukaryotes, notably the Bdelloid rotifers, have lost the ability to carry out meiosis and have acquired the ability to reproduce by parthenogenesis. Meiosis does not occur in archaea or bacteria, which reproduce via asexual processes such as mitosis or binary fission. During meiosis, the genome of a diploid germ cell, which is composed of long segments of DNA packaged into chromosomes, undergoes DNA replication followed by two rounds of division, resulting in haploid cells called gametes. Each gamete contains one complete set of chromosomes, or half of the genetic content of the original cell. These resultant haploid cells can fuse with other haploid cells of the opposite sex or mating type during fertilization to create a new diploid cell, or zygote. Thus, the division mechanism of meiosis is a reciprocal process to the joining of two genomes that occurs at fertilization. Because the chromosomes of each parent undergo genetic recombination during meiosis, each gamete, and thus each zygote, will have a unique genetic blueprint encoded in its DNA. In other words, meiosis and sexual reproduction produce genetic variation. Meiosis uses many of the same biochemical mechanisms employed during mitosis to accomplish the redistribution of chromosomes. There are several features unique to meiosis, most importantly the pairing and genetic recombination between homologous chromosomes. |
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duplication of sex cells
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The sperm and egg of living things. Sex cells have only half the number of chromosomes that other cells (body cells) have. (See meiosis.)
Reproduction without fertilization, reproduction without the joining of female and male gametes or sex cells. Common in aphids. Polyembryony: The reproduction of several embryos from a single egg. Two types: Type 1 - Early dividing cells separate and give rise to separate individuals. Type 2 - Later dividing cells give rise to separate individuals. Paedogenesis: Reproduction by immatures |
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Homozygous
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A person that carries two copies of the same allele at a give locus.
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HETROZYGOUS
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Heterozygous A person that carries two different alleles at a given locus
-Definition: Having two different alleles for a single trait. For example, the gene for seed shape in pea plants exists in two forms, one form or allele for round seed shape (R) and the other for wrinkled seed shape (r). A heterozygous plant would contain the following alleles for seed shape: (Rr). -ALLE, Related Terms • Genes • Heterozygous • Homozygous Definition: An alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome. For example, the gene for seed shape in pea plants exists in two forms, one form or allele for round seed shape (R) and the other for wrinkled seed shape (r). Organisms have two alleles for each trait. When the alleles of a pair are heterozygous, one is dominant and the other is recessive. The dominant allele is expressed and the recessive allele is masked. Using the previous example, round seed shape (R) is dominant and wrinkled seed shape (r) is recessive. Round: (RR) or (Rr), Wrinkled: (rr). |
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GENOTYPE
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Genotype (1) Genetic constitution of an individual.
(2) Specific alleles present at specific loci. |
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LAW OF SEGREGATION
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How are traits passed from parents to offspring? The answer is by gene transmission. Genes are located on chromosomes and consist of DNA. They are passed from parents to their offspring through reproduction. The principles that govern heredity were discovered by a monk named Gregor Mendel in the 1860's. One of these principles is now called Mendel's law of segregation.
Mendel worked with pea plants and selected seven traits to study that each occurred in two different forms. For instance, one trait he studied was pod color. Some pea plants have green pods and others have yellow pods. Since pea plants are capable of self fertilization, Mendel was able to produce true-breeding plants. A true-breeding yellow-pod plant for example would only produce yellow-pod offspring. Mendel then began to experiment to find out what would happen if he cross-pollinated a true-breeding yellow pod plant with a true-breeding green pod plant. He referred to the two parental plants as the parental generation (P generation) and the resulting offspring were called the first filial or F1 generation. |
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Mitosis
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Mitosis is the process in which a cell duplicates its chromosomes to generate two identical nuclei. It is generally followed by cytokinesis which divides the cytoplasm and cell membrane. This results in two identical cells with an equal distribution of organelles and other cellular components. Mitosis and cytokinesis jointly define the mitotic (M) phase of the cell cycle, the division of the mother cell into two sister cells, each with the genetic equivalent of the parent cell. Mitosis occurs most often in eukaryotic cells.
In multicellular organisms, the somatic cells undergo mitosis, while germ cells — cells destined to become sperm in males or ova in females — divide by a related process called meiosis. Prokaryotic cells, which lack a nucleus, divide by a process called binary fission. |
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Miosis
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In biology, meiosis (IPA: /maɪˈəʊsɪs/) is the process by which one diploid eukaryotic cell divides to generate four haploid cells often called gametes. The word "meiosis" comes from the Greek meioun, meaning "to make smaller," since it results in a reduction in chromosome number in the gamete cell. Among fungi, spores in which the haploid nuclei are at first disseminated are called meiospores, or more specifically, ascospores in asci (Ascomycota) and basidospores on basidia (Basidiomycota).
Meiosis is essential for sexual reproduction and therefore occurs in all eukaryotes (including single-celled organisms) that reproduce sexually. A few eukaryotes, notably the Bdelloid rotifers, have lost the ability to carry out meiosis and have acquired the ability to reproduce by parthenogenesis. Meiosis does not occur in archaea or bacteria, which reproduce via asexual processes such as mitosis or binary fission. During meiosis, the genome of a diploid germ cell, which is composed of long segments of DNA packaged into chromosomes, undergoes DNA replication followed by two rounds of division, resulting in haploid cells called gametes. Each gamete contains one complete set of chromosomes, or half of the genetic content of the original cell. These resultant haploid cells can fuse with other haploid cells of the opposite sex or mating type during fertilization to create a new diploid cell, or zygote. Thus, the division mechanism of meiosis is a reciprocal process to the joining of two genomes that occurs at fertilization. Because the chromosomes of each parent undergo genetic recombination during meiosis, each gamete, and thus each zygote, will have a unique genetic blueprint encoded in its DNA. In other words, meiosis and sexual reproduction produce genetic variation. Meiosis uses many of the same biochemical mechanisms employed during mitosis to accomplish the redistribution of chromosomes. There are several features unique to meiosis, most importantly the pairing and genetic recombination between homologous chromosomes. |
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duplication of sex cells
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The sperm and egg of living things. Sex cells have only half the number of chromosomes that other cells (body cells) have. (See meiosis.)
Reproduction without fertilization, reproduction without the joining of female and male gametes or sex cells. Common in aphids. Polyembryony: The reproduction of several embryos from a single egg. Two types: Type 1 - Early dividing cells separate and give rise to separate individuals. Type 2 - Later dividing cells give rise to separate individuals. Paedogenesis: Reproduction by immatures |
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Component Moleucles
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Molecular metals normally require charge transfer between two different chemical species. We prepared crystals of [Ni(tmdt)2] (tmdt, trimethylenetetrathiafulvalenedithiolate) and carried out crystal structure analyses and resistivity measurements. The analyses and measurements revealed that these single-component molecular crystals are metallic from room temperature down to 0.6 kelvin. Ab initio molecular orbital calculations suggested that molecular orbitals form conduction bands. The compact molecular arrangement, intermolecular overlap integrals of the highest occupied and lowest unoccupied molecular orbitals, and tight-binding electronic band structure calculation revealed that [Ni(tmdt)2] is a three-dimensional synthetic metal composed of planar molecules.
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Nucleotides
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A nucleotide is a chemical compound that consists of 3 portions: a heterocyclic base, a sugar, and one or more phosphate groups. In the most common nucleotides the base is a derivative of purine or pyrimidine, and the sugar is the pentose (five-carbon sugar) deoxyribose or ribose. Nucleotides are the monomers of nucleic acids, with three or more bonding together in order to form a nucleic acid.
Nucleotides are the structural units of RNA, DNA, and several cofactors - CoA, flavin adenine dinucleotide, flavin mononucleotide, adenosine triphosphate and nicotinamide adenine dinucleotide phosphate. In the cell they have important roles in metabolism and signaling. |
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The Double Helix-DNA forms a twisted, ladder-like structure that is often called a double helix. the "uprights" of the ladder are the sugers and phosophate groups while the "rungs" are the nuclotides. The ladder is twisted because the nucleotides.
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In the beginning of the 1950s, biologists knew that DNA carried the hereditary message. But how? The DNA molecule looks like a spiral ladder where the rungs are formed by base molecules, which occur in pairs. These sequences of base pairs represent the genetic information. The ladder is twisted because teh nucleotides are not the same size and they reach to attach to the suger molecules
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