Chapter 8: The Cellular Basis of Reproduction and Inheritance

Vocabulary flashcards covering the cellular basis of reproduction, inheritance, mitosis, and meiosis based on Chapter 8 of Campbell Biology: Concepts & Connections, Seventh Edition.

Cancer cells

Normal body cells that undergo genetic mutations, lose the ability to control the tempo of their own division, and run amok, causing disease.

Asexual reproduction

A method of reproduction that produces offspring identical to the original cell or organism and involves inheritance of all genes from one parent.

Sexual reproduction

A method of reproduction that produces offspring similar to the parents but with variations in traits, involving inheritance of unique sets of genes from two parents.

Binary fission

The process by which prokaryotes (Bacteria and Archaea) reproduce, where genes are carried on a single DNA molecule, the cell elongates, and the membrane grows inward to divide the parent into two daughter cells.

Chromatin

A combination of one long DNA molecule and proteins that help maintain structure and control gene activity, which makes up eukaryotic chromosomes.

Sister chromatids

Two identical copies of a duplicated chromosome joined together by a narrow "waist" called the centromere.

Centromere

The narrowed "waist" of a duplicated chromosome where the two sister chromatids are joined together.

Cell cycle

An ordered sequence of events extending from the time a cell is first formed from a dividing parent cell until its own division.

Interphase

A stage of the cell cycle involving the duplication of cell contents, consisting of the $G_1$ (growth), $S$ (duplication of chromosomes), and $G_2$ (preparation for division) phases.

Mitosis

The stage of the mitotic phase during which the nucleus and its contents, including the duplicated chromosomes, divide and are distributed into two daughter nuclei.

Cytokinesis

The stage of the mitotic phase where the cytoplasm is divided into separate cells.

Mitotic spindle

A structure composed of microtubules produced by centrosomes that is required to divide chromosomes during cell division.

Centrosomes

Cytoplasmic structures that organize microtubule arrangement and contain a pair of centrioles in animal cells.

Kinetochore

A protein structure on the centromere of sister chromatids where spindle microtubules attach during prometaphase.

Cleavage furrow

A shallow groove that forms in animal cells during cytokinesis, consisting of a contracting ring of microfilaments interacting with myosin.

Cell plate

A structure that forms in the middle of a plant cell during cytokinesis from vesicles containing cell wall material.

Growth factors

Proteins that stimulate cell division.

Density-dependent inhibition

A phenomenon in which crowded cells stop dividing.

Anchorage dependence

The requirement that cells must be in contact with a solid surface in order to divide.

Cell cycle control system

A cycling set of molecules that triggers and coordinates key events in the cell cycle through checkpoints such as $G_1$, $G_2$, and $M$.

Benign tumor

An abnormally growing mass of body cells that remains at its original site.

Malignant tumor

An abnormally growing mass of body cells that can spread into neighboring tissues and other parts of the body.

Metastasis

The spread of cancer cells to locations beyond their original site through the circulatory system.

Carcinomas

Cancers that originate in the external or internal body coverings.

Sarcomas

Cancers that arise in supportive and connective tissue.

Leukemias and lymphomas

Cancers that arise from blood-forming tissues.

Homologous chromosomes

A pair of chromosomes that are matched in length, centromere position, and gene locations.

Locus

The particular site or position where a gene is located on a chromosome.

Diploid

Cells or organisms that contain two homologous sets of chromosomes, one set inherited from each parent ($2n$).

Haploid

Cells that contain a single set of chromosomes ($n$), such as gametes.

Gametes

Sex cells, specifically sperm and eggs, which possess a single set of chromosomes.

Fertilization

The union of a haploid sperm cell and a haploid egg cell to produce a diploid zygote.

Zygote

The diploid ($2n$) cell resulting from fertilization, possessing one set of chromosomes from each parent.

Meiosis

A type of cell division that produces four genetically unique haploid gametes in diploid organisms through two consecutive cell divisions.

Tetrad

A structure formed during prophase I of meiosis consisting of four chromatids (a pair of homologous chromosomes).

Crossing over

The exchange of corresponding segments between nonsister chromatids of homologous chromosomes during prophase I of meiosis.

Chiasma

The specific site of attachment where crossing over occurs between nonsister chromatids.

Genetic recombination

The production of new combinations of genes due to the process of crossing over.

Karyotype

An ordered display of magnified images of an individual's chromosomes arranged in pairs, often arrested at metaphase of mitosis.

Trisomy 21

A human chromosome abnormality, also called Down syndrome, involving the inheritance of three copies of chromosome $21$.

Nondisjunction

An accident during meiosis in which members of a homologous pair or sister chromatids fail to separate normally.

Deletion

An alteration of chromosome structure involving the loss of a chromosome segment.

Duplication

An alteration of chromosome structure involving the repetition of a chromosome segment.

Inversion

An alteration of chromosome structure involving the reversal of a chromosome segment.

Translocation

The attachment of a chromosomal segment to a nonhomologous chromosome.

Chronic myelogenous leukemia (CML)

A leukemia affecting white blood cells that results from a reciprocal translocation where part of chromosome $22$ switches places with a fragment from chromosome $9$.