Biology 30 - Cell Division & Molecular Biology

A set of vocabulary flashcards based on key concepts from the Biology 30 lecture on cell division and molecular biology.

Deoxyribonucleic Acid (DNA)

Molecule responsible for the continuity of life, contains genetic information that is passed from parent to child.

Chromosome

Large segments of DNA found in the nucleus, humans have 23 pairs (total of 46 chromosomes).

Gene

Small segment of a chromosome that contains the code to build a particular protein, affecting traits like eye color and brain structure.

Nucleotide

Building block of DNA, consists of a deoxyribose sugar, phosphate group, and nitrogen base.

Purine

Larger double-ring nitrogen bases, specifically adenine (A) and guanine (G).

Pyrimidine

Smaller single-ring nitrogen bases, specifically cytosine (C) and thymine (T).

Double Helix

The spiral shape formed by two strands of DNA, which are twisted and held together by base pairs.

Mitochondrial DNA (mtDNA)

Circular DNA found in mitochondria, inherited maternally and contains genes essential for mitochondrial function.

Endosymbiotic Theory

Theory proposing that mitochondria and chloroplasts originated from smaller prokaryotic organisms engulfed by larger prokaryotes, leading to a symbiotic relationship.

Chargaff’s Rule

Observations that in DNA, the quantity of adenine (A) equals thymine (T) and the quantity of guanine (G) equals cytosine (C).

Watson and Crick

Researchers who created the first 3D model of DNA, termed the double helix, based on prior discoveries including Rosalind Franklin's X-ray diffraction images.

DNA Fingerprinting

Technique used to identify individuals based on unique DNA patterns, commonly applied in crime scene investigations and paternity testing.

Semi-Conservative Replication

Method of DNA replication where each new DNA molecule consists of one original strand and one newly synthesized strand.

Somatic Cells

Any cells in an organism that are not reproductive cells (gametes), containing the diploid number of chromosomes.

Mitosis

Process of somatic cell division that ensures equal distribution of identical chromosomes to daughter cells.

Meiosis

Type of cell division that results in four reproductive (gametes) cells, each with half the number of chromosomes as the parent cell.

Haploid

Cells containing half the number of chromosomes (n), typical of gametes (sperm and egg cells).

Diploid

Cells containing two sets of chromosomes (2n), typical of somatic cells.

Nondisjunction

Failure of chromosomes to segregate properly during meiosis, leading to gametes with abnormal chromosome numbers.

Mutagen

Agent that causes changes in DNA, which can result in mutations.

Genetic Engineering

Manipulation of an organism's DNA to achieve desired traits, often involving the insertion of foreign genes.

Recombinant DNA

DNA that contains genes from two different organisms, often used in genetic engineering.

Restriction Enzyme

Enzyme that cuts DNA at specific sequences, essential for recombinant DNA technology.

Gene Therapy

Use of genetic engineering techniques to treat or prevent disease by correcting defective genes.