Destiny CobbBiology

Chapter 8pgs.200-225

Main Idea Notes/Vocabulary

Section 8.1Cellular

Transport

Osmosis is the diffusion of water through a selectively permeable membrane. Passive Transport moves a substance with the concentration gradient and requires no energy from the cell. Active transport moves materials against the concentration gradient and requires energy to overcome the opposite flow of materials with the concentration gradient. Large particles may enter a cell by endocytosis and leave by exocytosis.Osmosis: Diffusion of WaterOsmosis- diffusion of water across a selectively permeable membrane depending on the concentration of solutes on either side of the membrane

-Isotonic solution- in cells, a solution in which the concentration of dissolved substance in the solution is the same as the concentration of dissolved substances inside the cell

-Hypotonic Solution- in cells, the solution in which the concentration of dissolved substances is lower in the solution outside the cell than the concentration inside the cell; causes cells to swell, and possibly burst as water enters the cell

-Hypertonic Solution- in cells, the solution in which the concentration of dissolved substances outside the cell is higher the concentration inside the cell; causes a cell to shrink as water leaves the cell

Passive TransportPassive Transport- movement of cell particles across cell membranes by diffusion of osmosis; the cell uses no energy to move particles across the membrane

-Facilitated Diffusion- passive transport of materials across a plasma membrane by transport proteins embedded in plasma membrane

Active TransportActive Transport- energy-expending process by which

Destiny CobbBiology

Chapter 8pgs.200-225

cells transport materials across the cell membrane against a concentration gradient

Transport of Large Particles:Endocytosis- active transport process where a cell engulfs materials with a portion of the cell’s plasma membrane and releases the contents inside the cell

Exocytosis- active transport process by which materials are secreted or expelled from a cell

Section 8.2Cell Growth and

Reproduction

Section 8.2Cell Growth and

Reproduction(continued)

Cell size is limited largely by the diffusion rate of a materials into and out of the cell, the amount of DNA available to program the cell’s metabolism, and the cell’s surface area-to-volume ratio. The life cycle of a cells divided into two genetic periods: a period of active growth and metabolism, known as interphase, and a period of cell division known as mitosis. Mitosis is divided into 4 phases: prophase, metaphase, anaphase, and telophase. The cells of most multicellular organisms are organized into tissues, organs, and organ system.

Cell ReproductionChromosome- cell structures that carry the genetic material that is copied and passed from generation to generation of cells

Chromatin- long, tangled strands of DNA found in the eukaryotic cell nucleus during interphase

Cell CycleCell Cycle- continuous sequence of growth (interphase) and division (mitosis) in a cell

Interphase- cell growth phase were a cell increases in size, carries on metabolism, and duplicates chromosomes prior to division

Mitosis- period of nuclear cell division in which two daughter cells are formed, each containing a complete set of chromosomesThe Phases of Mitosis:1) Prophase- 1st and longest phase of mitosis where chromatin coils into visible chromosomes

Destiny CobbBiology

Chapter 8pgs.200-225

Section 8.2Cell Growth and

Reproduction(continued)

A)Sister Chromatids- identical halves of a duplicated parent chromosome formed during the prophase stage of mitosis; the halves are held together by a centromeres

B)Centromere- cell structure that joins two sister chromatids of a chromosome

C)Centriole- in animal cells, a pair of small cylindrical structures composed of microtubules that duplicate during interphase and move to opposite ends of the cell during interphase

D)Spindle- cell structures composed of microtubules fibers; form between the centrioles during prophase and shorten during anaphase, pulling apart sister chromatids

2) Metaphase- short second phase of mitosis where doubled chromosomes move to the equator of the spindle and chromatids are attached by centromeres to a separate spindle fiber

3) Anaphase- phase of mitosis where the centromeres split and the chromatid pairs of each chromosome are pulled apart by microtubules

4) Telophase- final phase of mitosis during which new cells prepare for their own independent existence

Division of the CytoplasmCytokinesis- cell process following meiosis or mitosis in which the cell’s cytoplasm divides and separates into new cellsResult of MitosisTissue- group of cells that work together to perform a specific function

Organ- group of 2 or more tissues organized to perform complex activities within an organism

Organ System- multiple organs that work together to perform a specific life function

Section 8.3 The cell cycle is controlled by key enzymes that are

Destiny CobbBiology

Chapter 8pgs.200-225

Control of the Cell Cycle

produced at specific points in the cell cycle. Cancer is caused by genetic and environmental factors that change the genes that control the cell cycle. For some types of cancer, research has shown that lifestyle choices like eating a healthy diet and exercising regularly can reduce the incidence of cancer

Normal Control of the Cell CycleCancer- uncontrolled cell division that may be caused by environmental factors and/or changes in enzyme production in the cell cycle

Gene- segment of DNA that controls the protein production and the cell cycle