Zoology exam 1
About this set
Created by:
blondygal007 on September 14, 2011
Log in to favorite or report as inappropriate.
Order by
105 terms
Terms | Definitions |
|---|---|
 genes | the biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein |
| evolution | change in a kind of organism over time; process by which modern organisms have descended from ancient organisms |
| domain | Most inclusive taxonomic category; larger than a kingdom |
| hypothesis | possible explanation for a set of observations or possible answer to a scientific question |
| model/theory | A simplified conceptual picture based on experiment that explains how an aspect of nature occurs |
| ecosystem | a system formed by the interaction of a community of organisms with their physical environment |
| cells | the smallest unit of all living things |
| adaptation | inherited characteristic that improves an organism's ability to survive and reproduce in a particular environment |
| binomial nomenclature | two part scientfic name for an organism; its Genus is listed first, followed by its species and is always underlined or italicized |
| variable | A factor that can change in an experiment |
| population | a group of organisms of the same species populating a given area |
| biome | a natural community of plants and animals, its composition being largely controlled by climatic conditions. |
| homeostasis | a tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level |
| taxonomy | the science of describing, naming, and classifying organisms |
| scientific method | a series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions |
| control | the standard by which the test results can be compared |
| community | (ecology) a group of interdependent organisms inhabiting the same region and interacting with each other |
| biosphere | the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist |
| prokaryote | a unicellular organism having cells lacking membrane-bound nuclei |
| endosymbiotic hypothesis | Explanation of the origin of eukaryotic cells. Mitochondria and chloroplasts were one free living cells that became engulfed in another cell. |
| nucleus | a part of the cell containing DNA and RNA and responsible for growth and reproduction |
| chromatin | combination of DNA and protein molecules, in the form of long, thin fibers, making up the genetic material in the nucleus of a eukaryotic cell |
| ribosomes | small particle in the cell on which proteins are assembled; made of RNA and protein |
| lysosome | membrane-bound sac containing digestive enzymes that can break down proteins, nucleic acids, and polysaccharides |
| ATP | Adenosine triphosphate, a molecule that acts as the main energy source for cell processes |
| tubulin | a globular protein; constructs microtubules |
| intermediate filaments | Threadlike proteins that range from 7-11nm in diameter, and strengthen the cell and help maintain its shape, stabilize the positions of organelles, and stabilize the position of the cell with respect to surrounding cells through specialized attachment to the cell membrane |
| eukaryote | cell with a nucleus and membrane bound organelles; animals, plants, protists, fungi |
| autogenous model | eukaryotic cells evolved by invagination and specialization of internal membranes derived from a prokaryote; golgi bodies, vacuoles, ER |
| nuclear envelope | double membrane perforated with pores that control the flow of materials in and out of the nucleus |
| transcription | process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in RNA |
| Rough ER | studded with ribosomes, can be thought of as the cells membrane factory, proteins can be made in it |
| Smooth ER | Free of ribosomes. Synthesis of lipids, phospholipids and steroid sex hormones-help detoxify drugs and poisons (liver cells) involves adding hydroxyl groups to drugs to make soluble and easier to flush from body |
| autophagy | A process that describes lysosomes using their hydrolytic enzymes to recycle the cell's own organic material |
| cytoskeleton | contained within a cell's cytoplasm and is made out of protein. It has structures such as flagella, cilia and lamellipodia and plays important roles in both the movement of vesicles and organelles and cellular division. |
| actin filaments | a thin type of protein filament composed of actin proteins that forms part of the cytoskeleton and supports the plasma membrane and plays a key role in cell strength, shape and movement |
| centrioles | consist of two short cylinders of microtubules at right angles to each other and are situated in the cytoplasm near the nuclear envelope to help with cell division |
| cytoplasm | a jellylike fluid inside the cell in which the organelles are suspended |
| chromosomes | threadlike structure within the nucleus containing the genetic information (DNA) that is passed from one generation of cells to the next |
| translation | the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm |
| Golgi apparatus | An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulum. |
| mitochondrion | cell organelle that converts the chemical energy stored in food into energy (ATP) |
| microtubules | are hollow tubes, like plumbing pipes that maintain the shape of the cell and serve as tracks for organelles to move along within the cell |
| actin | Protein that composes microfilaments. Found in cytoskeleton myofibrils of muscle fiber, spindle fibers during cell division |
| cilia | short, hair-like structures made of microtubules that enable movement of cells or movement of materials outside a cell |
| rRNA | The most abundant type of RNA, which together with proteins froms the structure of ribosomes |
| nucleolus | The organelle where ribosomes are made, synthesized and partially assembled, located in the nucleus |
| cell theory | idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells |
| flagella | long, thin, whip-like structures, with a core of microtubules, that enable some cells to move |
| DNA | the genetic material that carries information about an organism and is passed from parent to offspring. |
| endomembrane system | A network of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles. |
| plasma/cell membrane | Fluid, semipermeable, lipid bilayer that surrounds all cells; provides support and protection; serves as a barrier between the cell and environment; controls the movement of materials in and out of the cell; helps to maintain homeostasis (biological balance) |
| selectively permeable | a property of cell membranes that allows some substances to pass through, while others cannot |
| facilitated diffusion | movement of specific molecules across cell membranes through protein channels |
| hypertonic | In comparing two solutions, referring to the one with a greater solute concentration |
| isotonic | when the concentration of two solutions is the same |
| active transport | energy-requiring process that moves material across a cell membrane against a concentration difference |
| phagocytosis | process in which extensions of cytoplasm surround and engulf large particles and take them into the cell |
| solution | A mixture that forms when one substance dissolves another |
| phospholipid bilayer | double-layered sheet that gives cell membranes a flexible structure that forms a strong barrier between the cell and its surroundings |
| dynamic equilibrium | result of diffusion where there is continuous movement particles but no overall change in concentration |
| carrier protein | a protein that transports substances across a cell membrane. |
| permeable | allowing (especially liquids) to pass or diffuse through |
| crenation | shrinkage of a cell caused by contact with a hypertonic solution (water taken out) |
| exocytosis | process of exporting proteins from a cell by a vesicle fusing with the plasma membrane and spilling the proteins outside the cell |
| solute | the substance that is dissolved |
| diffusion | process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated |
| passive | meaning no energy is required |
| osmosis | diffusion of water through a selectively permeable membrane |
| hypotonic | describes a solution whose solute concentration is lower than the solute concentration inside a cell |
| lyse | the death of a cell by bursting |
| endocytosis | the process by which a cell membrane surrounds a particle and encloses the particle in a vesicle to bring the particle into the cell |
| solvent | the substance in which the solute dissolves |
| genome | complete set of an organism's genetic material |
| chromatin | long strands of DNA found in the eukaryotic cell nucleus; condense to form chromosomes |
| karyokinesis | Division of the nucleus |
| synthesis phase | a cell's DNA is copied during this phase. at the end of this phase, each chromosome consists of two chromatids attached at the centromere |
| haploid | an organism or cell having only one complete set of chromosomes |
| anaphase | the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles |
| contractile ring | ring of actin filaments that pinches the cytoplasm between 2 daughter cells |
| cell cycle | series of events that cells go through as they grow and divide. |
| metastasis | The spread of cancer cells to locations distant from their original site. |
| gametes | reproductive cells, have only half the number of chromosomes as body cells |
| chromatid | one half of a duplicated chromosome |
| cytokinesis | division of the cytoplasm |
| G2 phase | the third and shortest phase of interphase, the second gap phase where many of the organelles and molecules required for cell division are produced |
| diploid | an organism or cell having two sets of chromosomes or twice the haploid number |
| spindle apparatus | structure made of spindle fibers, centrioles, and aster fibers that is involved in moving and organizing chromosomes before the cell divides |
| telophase | the final stage of mitosis or meiosis, during which a nuclear membrane forms around each set of new chromosomes |
| centromere | region where two sister chromatids are joined tightly together |
| cancer | any malignant growth or tumor caused by abnormal and uncontrolled cell division |
| somatic cells | any cell in multicellular organism except an egg or sperm |
| M phase | the phase in the cell cycle where mitosis and cytokinesis occur resulting in cell division |
| asters | fibers that radiate outward from each centriole |
| prophase | the first stage of mitosis or meiosis in eukaryotic cell division, during which the nuclear envelope breaks down and strands of chromatin form into chromosomes |
| kinetochore | A structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle. |
| benign | noncancerous; not harmful; a description of a tumor that is not able to spread from one area to another |
| replication | copy that is not the original |
| G1 phase | the first growth period of the cell cycle, during interphase, where the cell grows and organelles in the cytoplasm replicate |
| interphase | First phase of the cell cycle- including G1, S, G2 |
| centrosomes | made of 2 hollow cylinders called centrioles which are composed of microtubules and important in moving chromosomes during cell division |
| metaphase | second phase of mitosis, during which the chromosomes line up across the center of the cell |
| cleavage furrow | the area of the cell membrane that pinches in and eventually separates the dividing cell. Begins in telophase |
| G0 phase | a nondividing, stalled state that ensues when no go-ahead signal is received by the cell at the G1 checkpoint |
| malignant | harmful or cancerous |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.