Genetics

These regulatory sequences contain TFIIB recognition elements and initiator sequences that position RNA polymerase II for accurate transcription initiation. TFIID binding to TATA boxes nucleates pre-initiation complex assembly through sequential recruitment of general transcription factors. Enhancer sequences can influence these regions from considerable distances through DNA looping mediated by transcriptional activators and mediator complexes. These DNA sequences located upstream of coding regions serve as RNA polymerase II binding sites. s, name these gene regulatory elements.

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These structures contain palindromic sequences recognized by type II restriction endonucleases, often featuring inverted terminal repeats flanking internal coding sequences. Barbara McClintock's pioneering work revealed their capacity for autonomous movement through cut-and-paste mechanisms. Class II elements like Tc1/mariner superfamily members utilize transposase enzymes to excise themselves and integrate at TTAA target sites. These genetic elements can cause insertional mutagenesis and are responsible for anthocyanin variegation in maize kernels. s, name these mobile DNA sequences.

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This scientist's double helix model incorporated Chargaff's base-pairing rules and Franklin's X-ray crystallography data, revolutionizing molecular biology and genetics. Along with Francis Crick, he proposed the antiparallel structure of DNA with complementary nucleotide sequences. His later work included the discovery of messenger RNA and contributions to the Human Genome Project, earning him Nobel recognition for determining DNA structure. This American molecular biologist co-authored 'The Double Helix' and founded Cold Spring Harbor Laboratory. s, name this scientist who helped discover DNA structure.

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This unit of inherited traits is passed from parents to their offspring and determines characteristics like hair color, blood type, and height. Multiple versions of these, called alleles [[uh-LEELZ]], can exist for each trait. They are made of DNA and located on chromosomes. , name these units of heredity.

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During anaphase I of meiosis, homologous chromosomes are physically pulled to opposite poles of the cell, ensuring that allelic variants cannot co-travel into the same daughter cell. This principle was mathematically confirmed when Mendel crossed true-breeding purple and white pea plants and observed a 3:1 phenotypic ratio in the F2 generation. It establishes that each diploid organism carries two alleles per gene locus, but contributes only one to any given gamete. Also called the Law of Segregation, it is paired with the Law of Independent Assortment as one of Mendel's two foundational rules of heredity. , name this first law of inheritance, formulated by the father of genetics.

Hint: Segregation means separation — one allele per gamete, always.

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