| A | B |
|---|
| meristem | actively dividing cells |
| vascular cambium | produces secondary xylem, phloem to increase girth of stem and portions of roots |
| xylem | for transport of water minerals |
| phloem | for transport of nutrients |
| stomata | Pore in a plant's epidermis through which gases exchange between the plant and the atmosphere |
| guard cells | one of a pair of epideral cells that open and close stomata in plants by gaining and losing turgor pressure |
| transpiration | the movement of water vapor from plant parts to the atmosphere through open stomata |
| mesophyll | thin-walled plant cell that takes part in photosynthesis |
| epithelia | tightly packed cells that form linings and coverings |
| connective tissue | tissue type consisting of widely spaced cells in a matrix, includes loose and fibrous connective tissues, cartilage, bone, and blood |
| basement membrane | a thin,noncellular layer that anchors epithelial tissues to other tissues |
| ligaments | tough band of fibrous connective tissue that connects bone to bone across a joint |
| adipose tissue | a type of connective tissue consisting of cells laden with lipid |
| chondroytes | a cartilage cell |
| erythrocyte | red blood cell |
| leukocyte | white blood cell |
| platelets | a cell fragment that is part of the blood and orchestrates clotting |
| endocrine gland | a concentration of hormone producing cells in animals |
| exocrine gland | structure that secrets substances through ducts |
| hormones | a chemical synthesized in small quantities in one part of an organism and transported to anotherwhere it affects target cells |
| neurons | a nerve cell consisting of a cell body a long sending projection called dendrites |
| axons | an extension of a neuron that transmits messages away from the cell body and toward another cell |
| dendrites | thin neuron branch that receives neural messages and transmits information to the cell body |
| epidermis | the outermost cell layer of young roots stems and leaves. |
| dermis | the layer of skin, derived from mesoderm, that lies beeath the epidermis in vertebrates |
| hypodermis | an outer layer of a roundworm that secretes a protective cuticle |
| artieries | vessel that carries blood away from the heart |
| veins | a strand of vascular tissue in leaves., a vessel that returns blood to the heart |
| capillaries | tiny vessel that connects an arteriole with a venule |
| antibodies | protein that B cells secrete that recongnize and binds to foreign antigens, disabling them or signaling other cells to do so |
| antigens | the specific part of a molecule that elicits an immune response |
| ovulation | the release of an oocyte from an ovarian follicle |
| acrosome | a protrusion on the anterior end of a sperm cell containing digestive enzymes that enable the sperm cell containing digestive enzymes that enable the sperm to penetrate layers around the oocyte |
| corpus luteum | a gland formed from an ovarian follicle that has recently released an oocyte, produces estrogen and progesterone |
| endomertrium | the inner uterine lining |
| testes | male gonad containing seminferous tubules, where sperm are manufactured |
| spermatogenesis | the differentiation fo sperm cell from a doploid spermatogonium, to primary spermatocyte, two haploid secondaru s[ermatocytes to spermatids and finally to mature spermatozoa |
| oogenesis | the differentiation of an egg cell from a diploid oogonium |
| fertilization membrane | the union of two gametes of eukaryotic |
| zygote | the fused egg and sperm that develops into a diploid individual |
| karyotype | a size order chart of chromosomes |
| chromatids | a continuous strand of DNA comprising and unreplicated chromosome |
| mitosis | a form of cell division in which two genetically identical cells form from one |
| meiosis | cell divison that halves the genetic matrial |
| haploid | a cell with one copy of each chromosome |
| diploid | a cell with two copies of each chromosome |
| interphase | the period when the cell synthesizes proteins lipids carbohydrates, and nucleic acids |
| prophase | when synapsis and crossing over occurs |
| metaphase | the second stage of cell divison, which chromosomes align down the center of the cell |
| anaphase | the stage of mitosis when centromeres split and two sets of chromosomes part |
| telophase | the final stage of cell dicision when two cells form from one and the spindle is disassembled |
| cytokinesis | distribution of cytoplasm, organelles, and macromolecules into two progeny cells in cell divison |
| cell cycle | the life of a cell, in terms of whether it is divivding or in interphase |
| crossing over | exchanging of geneic material between homologous chromosomes during prohase of meiosis |
| alleles | an alternate form of a gene |
| homozygote | possessing two indentical alleles for a particular gene |
| heterozygote | possessing two different alleles for a particular gene |
| genotype | genetic constitution of an individual |
| phenotype | observable expression of a genotype |
| sex-linked inheiritance | a gene on the X chromosome or a strait that results from activity of such a gene |
| epistasis | a gene masking another gene's expression |
| pleiotropic genes | a genotype with multiple expression |
| mutations | a change in a gene or chromosome |
| point mutation | a change in a single DNA base |
| frame shift mutation | a mutationthat adds or deletes one or two DNA bases, altering the reading frame |
| replication | Alocally unwound portion of DNA where replication occurs |
| DNA polymerse | an enzyme that inserts new bases and corrects mismatched base pairs in DNA replication |
| transcription | manufacturing RNA from DNA |
| RNA polymerase | an enzyme that takes part in DNA replication and RNA transcription |
| translation | assembly of an amino acid chain according to the sequence of base triplets in a molecule of mRNA |
| codons | a triplet of mRNA bases that specifies a particular amino acid |
| anticodon | a three base sequence on one loop of a transfer RNA molecule that is complementary to an mRNA codon and joins an amino acid and its mRNA instructions |
| exon | the bases of a gene that code for amino acids |
| introns | bases of a gene that are transcribed but are excised from the mRNA before translation into protein |
| promoter | a control sequence near the start of a gene that attracts |
| operon | a series of genes with related functions and their controls |
| recombinant DNA | containing genetic material from two of more sources |
| plasmids | small, circular DNA apart from an organism chromosome |
