Biological Anthropology, Chapter 3 Genetics: Cells & Molecules

pedigree

a diagram used in the study of human genetics that shows the transmission of a genetic trait over generations of a family

prokaryotes

single-celled organisms, such as bacteria, in which the genetic material is not separated from the rest of the cell by a nucleus

eukaryotes

a cell that possesses a well-organized nucleus

nucleus

in eukaryotic cells, the part of the cell in which the genetic material is separated from the rest of the cell (cytoplasm) by a plasma membrane

cytoplasm

in a eukaryotic cell, the region within the cell membrane that surrounds the nucleus; it contains organelle, which carry out the essential functions of the cell, such as energy production, metabolism, and protein synthesis

somatic cells

the cells of the body that are not sex cells, cellular components of tissues (over 200 types)

gametes

the sex cells: sperm & eggs (aka ova)

stem cells

undifferentiated cells found in the developing embryo that can be induced to differentiate into a wide variety of cell types or tissues. also found in adults, although adult stem cells are not as totipotent as embryonic stem cells

totipotent stem cells

they can differentiate into any of the somatic cell types found in the fetus or adult

deoxyribonucleic acid (DNA)

a double-stranded molecule that is the carrier of genetic information. each strand is composed of a linear sequence of nucleotides; the two strands are held together by hydrogen bonds that form between complementary bases.

proteins

complex molecules formed from chains of amino acids (polypeptide) or from a complex of polypeptides. they function as structural molecules, transport molecules, antibodies, enzymes, and hormones.

protein synthesis

the assembly of proteins from amino acids that occurs at ribosomes in the cytoplasm and is based on information carried by mRNA.

ribonucleic acid (RNA)

single-stranded nucleic acid that performs critical functions during protein synthesis and comes in 3 forms: messenger RNA, transfer RNA, & ribosomal RNA

mitochondria

organelles in the cytoplasm of the cell where energy production for the cell takes place. contains its own DNA.

endoplasmic reticulum (ER)

an organelle in the cytoplasm consisting of a folded membrane.

ribosomes

structures composed primarily of RNA that are found on the endoplasmic reticulum. they are the site of protein synthesis.

nucleotide

molecular building block of nucleic acids DNA & RNA; consisting of a phosphate, sugar, and base

base

variable component of the nucleotides that form the nucleic acids DNA & RNA. In DNA, the bases are adenine, guanine, thymine, & cytosine. In RNA, uracil replaces thymine.

chromosome

discrete structure composed of condensed DNA and supporting proteins

karyotype

the complete chromosomal complement of an individual; usually based on a photograph of the chromosomes visualized under the microscope

mitosis

somatic cell division in which a single cell divides to produce two identical daughter cells

meiosis

cell division that occurs in the testes and ovaries that leads to the formation of sperm and ova (gametes), resulting in 4 daughter cells

human genome

all genetic info in a person

gene

the fundamental unit of hereditary. consists of a sequence of DNA bases that carries the info for synthesizing a protein and occupies a specific chromosomal locus.

exon

a segment of a DNA or RNA molecule containing information coding for a protein or peptide sequence

intron

a segment of a DNA or RNA molecule that does not code for proteins and interrupts the sequence of genes