domingo, 10 de julio de 2011

.::Vocabulary of Concepts of Ch.33 Animal tissue::.

1.       adhering junction:           Junction where a mass of anchored proteins help adjoining cells adhere.

2.       adipose tissue:  A connective tissue having an abundance of fat-storing cells.

3.       blood:    Fluid connective tissue of water, solutes, and formed elements (blood cells, platelets). Transports substances to and from cells, helps maintain internal environment.

4.       bone tissue:       Of vertebrate skeleton, a tissue of osteoblast secretions hardened with minerals.

5.       cardiac muscle tissue:    A contractile tissue that is present only in the heart wall.

6.       cartilage:              Connective tissue with solid, pliable intercellular material that resists compression.

7.       dense, irregular connective tissue:          Animal tissue with fibroblasts, many asymmetrically positioned fibers in ground substance. In skin and some capsules around organs.

8.       dense, regular connective tissue:            Animal tissue with rows of fibroblasts between parallel bundles of fibers. In tendons, elastic ligaments.

9.       ectoderm:           The first-formed, outermost primary tissue layer of animal embryos; gives rise to nervous system tissues and integument's outer layer.

10.   endocrine gland:              Ductless gland that secretes hormones, which the bloodstream distributes.

11.   endoderm:         Inner primary tissue layer of animal embryos; source of inner gut lining and derived organs.

12.   epithelium:         Animal tissue that covers external surfaces and lines internal cavities and tubes. One surface is free and the other rests on a basement membrane.

13.   exocrine gland: Glandular structure that secretes products, usually through ducts or tubes, to a free epithelial surface.

14.   gap junction:      Cylindrical arrays of proteins in the plasma membrane that pair up as open channels for signals between adjoining cells.

15.   gland cell:            A cell that secretes products unrelated to their own metabolism for use elsewhere

16.   homeostasis:     State in which physical and chemical aspects of internal environment (blood, interstitial fluid) are being maintained within ranges suitable for cell activities.

17.   internal environment:   Blood + interstitial fluid.

18.   loose connective tissue:               Animal tissue with fibers, fibroblasts loosely arrayed in semifluid ground substance.

19.   mesoderm:         Primary tissue layer of all large, complex animals; gives rise to many internal organs and part of the integument.

20.   nervous tissue: Connective tissue composed of neurons and often neuroglia.

21.   neuroglia:            Collectively, cells that structurally and metabolically support neurons. They make up about half the volume of nervous tissue in vertebrates.

22.   neuron:                Type of nerve cell; basic communication unit in most nervous systems.

23.   organ:    Body structure with definite form and function that consists of more than one tissue.

24.   organ system:    Organs interacting chemically, physically, or both in a common task.

25.   skeletal muscle tissue:   Striated contractile tissue that is the functional partner of bone.

26.   smooth muscle tissue:   Nonstriated contractile tissue found in soft internal organs.

27.   tight junction:    Cell junction where strands of fibrous proteins oriented in parallel with a tissue's free surface collectively block leaks between the adjoining cells.

28.   tissue:   Of multicelled organisms, a group of cells and intercellular substances that function together in one or more specialized tasks.

sábado, 9 de julio de 2011

.::Vocabulary of Concepts of Ch.20 Origin and evolution of life::.

1.      angiosperm:       Flowering plant.

2.       archaebacterium:            Member of the prokaryotic domain Archaebacteria

3.       Archean eon:     Eon in which life arose (3.8-2.5 bya).

4.       big bang:              Model for origin of universe.

5.       Cenozoic era:     The present era (65 mya to present).

6.       crust of Earth:   Outer zone of low-density rocks resting on the Earth's mantle.

7.       dinosaur:             One of a fabulous group of reptiles that originated in the Triassic and became the dominant land vertebrates for 125 million years.

8.       Ediacaran:            One of the species with a highly flattened body that arose in the precambrian.

9.       endosymbiosis theory:  Continuing physical contact between two species, one of which lives and reproduces inside the other's body.

10.   eubacterium:     Prokaryotic cell; has a nucleoid, but no nucleus, cytoplasm, or cell membrane; most have a cell wall, some encapsulated.

11.   eukaryotic cell:  Cell having a nucleus and other membrane-bound organelles.

12.   global broiling hypothesis:           Theory that an asteroid impact caused the K-T mass extinction by creating a colossal fireball, the debris from which raised global air temperature by thousands of degrees.

13.   gymnosperm:    Type of vascular plant in which seeds form on exposed surfaces of reproductive structures (e.g., on cone scales).

14.   K-T asteroid impact theory:         A huge asteroid hit Earth at the K-T boundary; last dinosaurs perished during the mass extinction.

15.   mantle: Of mollusks, a tissue draped over the visceral mass. Of Earth, a zone of intermediatedensity rocks beneath the crust.

16.   Mesozoic era:    An era (240-65 mya) of spectacular expansion in the range of global diversity.

17.   Paleozoic era:    Era from Cambrian, Ordovician, Silurian, Devonian, Carboniferous, through the Permian (544 to 248 mya).

18.   prokaryotic cell:                Archaebacterium or eubacterium; single-celled organism, most often walled; lacks the profusion of membranebound organelles observed in eukaryotic cells.

19.   Proterozoic eon:              Period from 2.5 billion to 570 million years ago; period during which eukaryotic cells arose.

20.   protistan:             Photoautotroph or heterotroph (or both) unlike bacteria; some like earliest eukaryotic cells. Has a nucleus, larger ribosomes, mitochondria, ER, Golgi bodies, chromosomes with numerous proteins, and cytoskeletal microtubules. Range in size from microscopic algae to giant kelps.

21.   proto-cell:           Hypothetic cell-like stage between chemical evolution and the first living cell.

22.   RNA world:         One model for prebiotic evolution in which RNA was the template for protein synthesis before the evolution of DNA.

23.   stromatolite:      Fossilized mats of shallow-water microbial communities, mainly cyanobacteria, from Archean to precambrian. Cell secretions blocked UV radiation but trapped sediments, and new mats grew on old ones; some are half a mile thick and hundreds of miles across.