Bio VOCAB 3-1 - 3-5

Genetics

The study of how traits are inherited and vary in organisms.

Chromosome

A structure made of DNA and proteins that carries genetic information; humans have 23 pairs.

Chromatin

The loose, uncoiled form of DNA and proteins found in the nucleus, which condenses to form chromosomes during cell division.

Replication

The process of copying DNA before cell division, ensuring each new cell gets an identical set of genetic instructions.

Histone

A protein that DNA wraps around, helping to organize and compact it into chromatin.

Gene

A segment of DNA that contains instructions for making a protein or determining a trait.

Allele

Different forms of the same gene that can result in variations of a trait.

Base Pairing

The specific matching of DNA bases: adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G).

DNA Polymerase

An enzyme that builds new DNA strands during replication by adding complementary nucleotides.

Spindle

A structure made of microtubules that helps separate chromosomes during cell division.

Mitosis

Cell division that produces two identical daughter cells for growth, repair, or asexual reproduction.

Meiosis

A type of cell division that produces gametes with half the chromosomes, increasing genetic diversity.

Interphase

The phase of the cell cycle where the cell grows, performs normal functions, and replicates its DNA.

Prophase

The first stage of mitosis, where chromosomes condense, the nuclear envelope breaks down, and spindle fibers form.

Metaphase

The stage of mitosis where chromosomes align in the center of the cell.

Anaphase

The stage of mitosis where sister chromatids are pulled to opposite sides of the cell.

Telophase

The stage of mitosis where chromosomes uncoil and nuclear envelopes re-form around each set of chromosomes.

Cytokinesis

The division of the cytoplasm, resulting in two separate cells.

Diploid

A cell with two sets of chromosomes, one from each parent (e.g., body cells).

Haploid

A cell with one set of chromosomes, as seen in gametes like sperm and eggs.

Messenger RNA (mRNA)

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

Transfer RNA (tRNA)

RNA that transports amino acids to the ribosome during protein synthesis.

Ribosomal RNA (rRNA)

RNA that helps form the ribosome, where proteins are assembled.

Transcription

The process where DNA is copied into mRNA in the nucleus, providing instructions for protein production.

Translation

The process where ribosomes read mRNA to link amino acids into a protein.

Codon

A three-base sequence in mRNA that codes for a specific amino acid.

Anticodon

A three-base sequence in tRNA that matches a codon in mRNA.

Intron

A non-coding segment of RNA that is removed during RNA processing.

Exon

A coding segment of RNA that remains after processing and is used to make proteins.

RNA Polymerase

The enzyme that builds RNA from a DNA template during transcription.

Genetic Engineering

Manipulating an organism’s DNA using biotechnology to modify traits, like creating disease-resistant crops or producing medicines.

Clone

A genetically identical copy of an organism, cell, or gene.

Recombinant DNA

DNA created by combining genetic material from different organisms.

Transgenic

An organism that contains genes from another species.

Plasmid

A small circular DNA molecule in bacteria, often used in genetic engineering to transfer genes.

Mutation

A change in DNA that can occur randomly or from environmental factors, potentially affecting traits or causing disorders.

Point Mutation

A change in a single nucleotide of the DNA sequence.

Frameshift Mutation

A mutation caused by adding or deleting a nucleotide, shifting the reading frame of the genetic code.

Selective Breeding

The process of breeding organisms with desired traits to enhance those traits in offspring.

Hybridization

Crossing different species or varieties to produce offspring with a combination of traits.

Trait

A specific characteristic of an organism, such as eye color or height.

Genotype

The genetic makeup of an organism, represented by its alleles (e.g., AA, Aa).

Phenotype

The observable traits of an organism resulting from its genotype and environment.

Zygote

A fertilized egg cell formed when a sperm and egg unite.

Homozygous

Having two identical alleles for a particular gene.

Heterozygous

Having two different alleles for a particular gene.

Segregation

The separation of alleles during gamete formation in meiosis.

Independent Assortment

The random distribution of genes into gametes, increasing genetic variation.

Incomplete Dominance

A form of inheritance where neither allele is fully dominant, resulting in a blended trait.

Hybrid

The offspring of two different species or varieties, combining traits from both parents.