Title: Biology
Content:  the mitochondria, chloroplasts, or other locations is collectively known as a cell's genome. In eukaryotes, genomic DNA is localized in the cell nucleus, or with small amounts in mitochondria and chloroplasts. In prokaryotes, the DNA is held within an irregularly shaped body in the cytoplasm called the nucleoid. The genetic information in a genome is held within genes, and the complete assemblage of this information in an organism is called its genotype. Genes encode the information needed by cells for the synthesis of proteins, which in turn play a central role in influencing the final phenotype of the organism. The 
Title: Cell (biology)
Content: Cell nucleus: A cell's information center, the cell nucleus is the most conspicuous organelle found in a eukaryotic cell. It houses the cell's chromosomes, and is the place where almost all DNA replication and RNA synthesis (transcription) occur. The nucleus is spherical and separated from the cytoplasm by a double membrane called the nuclear envelope. The nuclear envelope isolates and protects a cell's DNA from various molecules that could accidentally damage its structure or interfere with its processing. During processing, DNA is transcribed, or copied into a special RNA, called messenger RNA (mRNA). This mRNA is then transported out of the nucleus, where it is translated into a specific protein molecule. The nucleolus is a specialized region within the nucleus where ribosome subunits are 
Title: Centrosome
Content:   In cell biology, the centrosome (Latin centrum 'center' + Greek sōma 'body') (also called cytocenter ) is an organelle that serves as the main microtubule organizing center (MTOC) of the animal cell, as well as a regulator of cell-cycle progression. The centrosome provides structure for the cell. The centrosome is thought to have evolved only in the metazoan lineage of eukaryotic cells. Fungi and plants lack centrosomes and therefore use other structures to organize their microtubules. Although the centrosome has a key role in efficient mitosis in animal cells, it is not essential in certain fly and flatworm species. Centrosomes are composed of two centrioles arranged at right angles to each other, and surrounded by a dense, highly structured mass of protein termed the pericentriolar material (PCM). The PCM contains proteins responsible for microtubule nucleation and anchoring — including γ-tubulin, pericentrin and ninein. In general, each centriole of the centrosome is based on a nine-triplet microtubule assembled in a cartwheel structure, and contains centrin, cenexin and tektin. In many cell types, the centrosome is replaced by a cilium during cellular differentiation. However, once the cell starts to divide, the cilium is replaced again by the centrosome.
Title: Cell nucleus
Content:  The nucleus provides a site for genetic transcription that is segregated from the location of translation in the cytoplasm, allowing levels of gene regulation that are not available to prokaryotes. The main function of the cell nucleus is to control gene expression and mediate the replication of DNA during the cell cycle. The nucleus is an organelle found in eukaryotic cells. Inside its fully enclosed nuclear membrane, it contains the majority of the cell's genetic material. This material is organized as DNA molecules, along with a variety of proteins, to form chromosomes.
Title: Nuclear organization
Content:   The last level of organization concerns the distinct positioning of individual chromosomes within the nucleus. The region occupied by a chromosome is called a chromosome territory (CT). Among eukaryotes, CTs have several common properties. First, although chromosomal locations are not the same across cells within a population, there is some preference among individual chromosomes for particular regions. For example, large, gene-poor chromosomes are commonly located on the periphery near the nuclear lamina while smaller, gene-rich chromosomes group closer to the center of the nucleus. Second, individual chromosome preference is variable among different cell types. For example, the X-chromosome has shown to localize to the periphery more often in liver cells than in kidney cells. Another conserved property of chromosome territories is that homologous chromosomes tend to be far apart from one another during cell interphase. The final characteristic is that the position of individual chromosomes during each cell cycle stays relatively the same until the start of mitosis. The mechanisms and reasons behind chromosome territory characteristics is still unknown and further experimentation is needed.
Title: Cell nucleus
Content:   The cell nucleus contains the majority of the cell's genetic material in the form of multiple linear DNA molecules organized into structures called chromosomes. Each human cell contains roughly two meters of DNA. During most of the cell cycle these are organized in a DNA-protein complex known as chromatin, and during cell division the chromatin can be seen to form the well-defined chromosomes familiar from a karyotype. A small fraction of the cell's genes are located instead in the mitochondria. There are two types of chromatin. Euchromatin is the less compact DNA form, and contains genes that are frequently expressed by the cell. The other type, heterochromatin, is the more compact form, and contains DNA that is infrequently transcribed. This structure 
Title: Heredity
Content:  DNA is copied, so that each of the resulting two cells will inherit the DNA sequence. A portion of a DNA molecule that specifies a single functional unit is called a gene; different genes have different sequences of bases. Within cells, the long strands of DNA form condensed structures called chromosomes. Organisms inherit genetic material from their parents in the form of homologous chromosomes, containing a unique combination of DNA sequences that code for genes. The specific location of a DNA sequence within a chromosome is known as a locus. If the DNA sequence at a particular locus varies between individuals, the different forms of this sequence are 
Title: Cell theory
Content: Energy flow occurs within cells. ; Heredity information (DNA) is passed on from cell to cell. ; All cells have the same basic chemical composition. The modern version of the cell theory includes the ideas that:
Title: Cell biology
Content: Nucleus: The nucleus of the cell functions as the genome and genetic information storage for the cell, containing all the DNA organized in the form of chromosomes. It is surrounded by a nuclear envelope, which includes nuclear pores allowing for transportation of proteins between the inside and outside of the nucleus. This is also the site for replication of DNA as well as transcription of DNA to RNA. Afterwards, the RNA is modified and transported out to the cytosol to be translated to protein. ; Nucleolus: This structure is within the nucleus, usually dense and spherical in shape. It is the site of ribosomal RNA (rRNA) synthesis, which is 
Title: DNA
Content:  Genomic DNA is tightly and orderly packed in the process called DNA condensation, to fit the small available volumes of the cell. In eukaryotes, DNA is located in the cell nucleus, with small amounts in mitochondria and chloroplasts. In prokaryotes, the DNA is held within an irregularly shaped body in the cytoplasm called the nucleoid. The genetic information in a genome is held within genes, and the complete set of this information in an organism is called its genotype. A gene is a unit of heredity and is a region of DNA that influences a particular characteristic in an organism. 

Question: what is the center of heredity in a cell?
Answer: nucleus.
Cell nuclei.
the nucleus.
chromosome.