Chapter_4_Study_Guide

Nucleotide

The basic building block of DNA and RNA, made up of a sugar, phosphate group, and nitrogenous base.

Base Pair

The combination of adenine with thymine (A-T) or guanine with cytosine (G-C) in DNA.

Complementary Base Pairing

The principle stating that the sequence of one strand of DNA can determine the sequence of the other strand.

Chromatin

A complex of DNA and proteins that forms chromosomes within the nucleus.

Chromosome

A structure composed of DNA and proteins that carries genetic information.

Sister Chromatids

Two identical copies of a chromosome connected at a centromere.

RNA

Ribonucleic acid, a single-stranded nucleic acid involved in protein synthesis.

mRNA (messenger RNA)

RNA that carries genetic information from DNA to the ribosome for protein synthesis.

tRNA (transfer RNA)

RNA that helps translate mRNA into a protein by bringing the appropriate amino acids.

Transcription

The process of copying a segment of DNA into RNA.

Translation

The process of converting the language of nucleotides into the language of amino acids.

Gene

An information-containing segment of DNA that codes for a molecule of RNA and often for a protein.

Genome

The complete set of DNA, including all of its genes, in an organism.

Mutation

A change in the DNA sequence that can lead to changes in the structure and function of proteins.

Karyotype

A visual representation of the chromosomes in a cell, arranged in pairs.

Haploid

A cell that contains one complete set of chromosomes, typical of sperm and egg cells.

Diploid

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

Allele

Different forms of a single gene found at the same locus on homologous chromosomes.

Phenotype

The observable traits of an individual, resulting from the interaction of its genotype with the environment.

Genotype

The genetic constitution of an individual, representing the alleles inherited from the parents.

Codominance

A form of inheritance where both alleles in a heterozygote are fully expressed.

Polygenic Inheritance

A trait controlled by multiple genes, leading to a range of phenotypes.

Pleiotropy

The phenomenon where a single gene influences multiple traits.

Epigenetics

The study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence.