Chapter 2 - Table 1-Table 1

Question 1

Pedigree

Answer 1

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

Question 2

Prokaryotes

Answer 2

Single celled organisms, such as bacteria, in which the genetic material is not separated by a nucleus.

Question 3

Eukaryotes

Answer 3

A cell with a well-organized nucleus.

Question 4

Nucleus

Answer 4

Part of the cell in which the genetic material is separated from the rest of the cell (cytoplasm) by a plasma membrane.

Question 5

Cytoplasm

Answer 5

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

Question 6

Somatic Cells

Answer 6

Body cells that aren’t sex cells.

Question 7

Gametes

Answer 7

Sex cells.

Question 8

Stem Cells

Answer 8

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.

Question 9

DNA

Answer 9

A double-stranded molecule that carries genetic information. Composed of a linear sequence of nucleotides; the two strands are held together by hydrogen bonds that form between complementary bases.

Question 10

Proteins

Answer 10

Complex molecules formed from chains of polypeptide amino acids or from a complex of polypeptides. Function as structural molecules, transport molecules, antibodies, enzymes, and hormones.

Question 11

Protein Synthesis

Answer 11

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

Question 12

RNA

Answer 12

Single stranded nucleic acid that performs critical functions during protein synthesis and comes in mRNA, tRNA, and ribosomal RNA.

Question 13

Mitochondria

Answer 13

Organelles in the cytoplasm of the cell where energy production for the cell takes place. Contains its own DNA.

Question 14

Endoplasmic Reticulum (ER)

Answer 14

An organelle in the cytoplasm consisting of a folded membrane.

Question 15

Ribosomes

Answer 15

Structures composed primarily of RNA, which are found on the endoplasmic reticulum. Site of protein synthesis.

Question 16

Nucleotide

Answer 16

Molecular building block of nucleic acids DNA and RNA. Consists of a phosphate, a sugar, and a base.

Question 17

Base

Answer 17

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

Question 18

Enzyme

Answer 18

A complex protein that is a catalyst for chemical processes in the body.

Question 19

Hemoglobin

Answer 19

Protein found in red blood cells that transports oxygen.

Question 20

Hormone

Answer 20

A natural substance (often a protein) produced by specialized cells in one location of the body that influences the activity or physiology of cells in a different location.

Question 21

Amino Acids

Answer 21

Molecules that form the basic building blocks of protein.

Question 22

Polypeptide

Answer 22

A molecule made up of a chain of amino acids.

Question 23

Genetic Code

Answer 23

The system whereby the nucleotide triplets in DNA and RNA contain the information for synthesizing proteins from the 20 amino acids.

Question 24

Codon

Answer 24

A triplet of nucleotide bases in mRNA that specifies an amino acid or the initiation or termination of a polypeptide sequence.

Question 25

Gene

Answer 25

The fundamental unit of heredity. Consists of a sequence of DNA bases that carries the information for synthesizing a protein (or polypeptide) and occupies a specific chromosomal locus.

Question 26

mRNA

Answer 26

Strand of RNA synthesized in the nucleus as a complement to a specific gene (transcription). It carries the information for a sequence of amino acids to make a specific protein into the cytoplasm, where it is read at a ribosome and a protein molecule is synthesized (translation).

Question 27

tRNA

Answer 27

RNA molecules that bind to specific amino acids and transport them to ribosomes to be used during protein synthesis.

Question 28

Chromatin

Answer 28

The diffuse form of DNA as it exists during the interphase of the cell cycle.

Question 29

Mitosis

Answer 29

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

Question 30

Meiosis

Answer 30

Cell division that occurs in the testes and ovaries that leads to formation of gametes.

Question 31

Chromosomes

Answer 31

Discrete structures composes of condensed DNA and supporting proteins.

Question 32

Centromere

Answer 32

Condense and constricted region of a chromosome. During mitosis and meiosis, location where sister chromatids attach to one another.

Question 33

Diploid Number

Answer 33

Full complement of paired chromosomes in a somatic cell.

Question 34

Haploid Number

Answer 34

The number of chromosomes found in a gamete, representing one from each pair found in a diploid somatic cell.

Question 35

Homologous Chromosomes

Answer 35

Members of the same pair of chromosomes (or autosomes). Homologous chromosomes undergo crossing over during meiosis.

Question 36

Alleles

Answer 36

Alternative versions of a gene. Alleles are distinguished from one another by their differing effects on the phenotypic expression of the same gene.

Question 37

Homozygous

Answer 37

Having the same allele at the loci for a gene on both members of a pair of homologous chromosome.

Question 38

Locus

Answer 38

The location of a gene on a chromosome. The locus for a gene is identified by the number of the chromosome on which it is found and its position on the chromosome.

Question 39

Heterozygous

Answer 39

Having two different alleles at the loci for a gene on a pair of homologous chromosomes (or autosomes).

Question 40

Zygote

Answer 40

A fertilized egg.

Question 41

Crossing Over

Answer 41

Exchange of genetic material between homologous chromosomes during the first prophase of meiosis; mechanism for genetic recombination.

Question 42

Recombination

Answer 42

The rearrangement of genes on homologous chromosomes that occurs during crossing over in meiosis. The source of variation arising out of sexual reproduction; important for increasing rates of natural selection.

Question 43

Karyotype

Answer 43

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

Question 44

Autosomes

Answer 44

Any of the chromosomes other than the sex chromosomes.

Question 45

Sex Chromosomes

Answer 45

In mammals, chromosomes X and Y, with XX producing females and XY producing males.

Question 46

Nondisjunction Error

Answer 46

The failure of homologous chromosomes (chromatids) ti separate properly during cell division. When it occurs during meiosis, it may lead to the formation of gametes that are missing a chromosome or have an extra copy of a chromosome.

Question 47

Genome

Answer 47

The sum total of all the genes carried by an individual.

Question 48

Polymerase Chain Reaction (PCR)

Answer 48

Method for amplifying DNA sequences using the Taq polymerase enzyme. Can potentially produce millions or billions of copies of a DNA segment starting from a very small number of target DNA.

Question 49

mitochondrial DNA (mtDNA)

Answer 49

Small loop of DNA found in the mitochondria. It is clonally and maternally inherited.