anaphy 2M

cell

the basic living unit of all organisms

organelles

specialized structures within cells that performs specific functions

nucleus

an organelle containing the cell’s genetic material.

cytoplasm

The living material surrounding the nucleus and it contains many types of organelles

cell metabolism and energy use
synthesis of molecules
communication
reproduction and inheritance

what are the four main functions of a cell

cell membrane or plasma membrane

the outermost component of a cell

phospholipids and proteins

what are the two molecules the make up the cell membrane

fluid-mosaic model

Studies of the arrangement of molecules in the cell membrane have given rise to a model of its structure called…

plasma membrane, nucleus, cytoplasm, and organelles

what are the general parts of a cell

nucleus

Contains genetic material of cell (DNA) and nucleoli; site of RNA synthesis and ribosomal subunit assembly

ribosomes

site of protein synthesis

rough ER

has many ribosomes attached; site of protein synthesis

smooth ER

site of lipid synthesis; participates in detoxification

golgi apparatus

modifies protein structure and packages proteins in secretory vesicles

secretory vesicles

Contains materials produced in the cell; formed by the Golgi apparatus; secreted by exocytosis

lysosome

Contains enzymes that digest material taken into the cell; formed by the Golgi apparatus

peroxisome

Breaks down fatty acids, amino acids, and hydrogen peroxide

mitochondrion

Site of aerobic respiration and the major site of ATP synthesis

microtubule

Supports cytoplasm; assists in cell division and forms components of cilia and flagella

centrioles

Facilitate the movement of chromosomes during cell division

cilia

Move substances over surfaces of certain cells

flagella

propel sperm cells

microvilli

increase surface area of certain cells

concentration diffrence

occurs when a solute is not evenly distributed in a solvent

passive membrane transport

membrane transport that does not require the cell to expend energy

active membrane transport

membrane transport that requires the cell to expend energy, usually in the form of ATP

diffusion
osmosis
facilitated diffusion

what are the passive membrane transport?

active transport
secondary active transport
endocytosis
exocytosis

what are the active membrane transport?

diffusion

movement of solutes from a lower concentration of solutes to the higher concentration of solutes

diffusion

results from the natural, constant random motion of all solutes in a solution

concentration gradient

the difference in the concentration of a solute in a solvent between two points divided by the distance between the two points.

diffusion

With the concentration gradient through the lipid portion of the cell membrane or through membrane channels

osmosis

With the concentration gradient (for water) through the lipid portion of the cell membrane or through membrane channels

facilitated diffusion

With the concentration gradient by carrier molecules

active transport

Against the concentration gradient* by carrier molecules

secondary active transport

Against the concentration gradient by carrier molecules; the energy for secondary active transport of one substance comes from the concentration gradient of another

endocytosis

Movement into cells by vesicles

exocytosis

Movement out of cells by vesicles

osmosis

the diffusion of water across a selectively permeable membrane, such as the cell membrane, from a region of higher water concentration to one of lower water concentration

osmotic pressure

the force required to prevent the movement of water across a selectively permeable membrane

hydrostatic pressure

pushes water out of the tube back into the distilled water surrounding the tube.

isotonic solutions

solution where the concentrations of various solutes and water are the same on both sides of the cell membrane.

hypotonic, hypertonic, and isotonic solutions

types of solution in osmosis

hypertonic solution

solution has a higher concentration of solutes and a lower concentration of water relative to the cytoplasm of the cell.

hypotonic solution

solution has a lower concentration of solutes and a higher concentration of water relative to the cytoplasm of the cell

crenation

what happens to the cell when placed in a hypertonic solution

lysis

what happens to the cell when placed to a hypotonic solution?

facilitated diffusion

a mediated transport process, involving membrane proteins such as channels or carrier proteins, to move substance across the cell membrane.

size, shape, and charge

what are the characteristics of an ion or molecules to determine whether it can pass through a channel?

leak channels and gated channels

two classes of cell membrane channels

leak channels

cell membrane channel that constantly allow ions to pass through

gated channels

cell membrane channel that limits the movement of ions across the membrane by opening and closing

carrier molecules

proteins within the cell membrane which are also involved in facilitated diffusion

primary active transport

a process that utilizes membrane proteins to move substances across the cell membrane from regions of lower concentration to those of higher concentration, against a concentration gradient

cystic fibrosis

a genetic disorder that affects the active transport of Cl- into cells.

secondary active transport

involves the active transport of one substance, such as Na+, across the cell membrane, establishing a concentration gradient, which then provides the energy for moving a second substances across the membrane.

cotransport

the diffusing substance moves in the same direction as the transported substance

countertransport

the diffusing substance moves in a direction opposite to that of the transported substance.

endocytosis

the uptake of material through the cell membrane by the formation of a vesicle

phagocytosis

often used for endocytosis when solid particles are ingested.

pinocytosis

distinguished from phagocytosis in that much smaller vesicles are formed, and they contain liquid rather than solid particles.

exocytosis

the release of substances from the cell through the fusion of a vesicle with the cell membrane

transcytosis

a substance is taken into the cell by endocytosis, the vesicle is moved across the cell, and the substance is then released from the cell by exocytosis.

nucleus

a large organelle within the cell

nuclear envelope

The contents of the nucleus is separated from the rest of the cytoplasm by…

nuclear pores

passageways through which materials can move into or out of the nucleus.

chromatin

chromosomes are loosely coiled and are collectively called…

nucleoli

are diffuse bodies with no surrounding membrane that are found within the nucleus

ribosomes

the organelles where proteins are produced

endoplasmic reticulum

a series of membranes forming sacs and tubules that extends from the outer nuclear membrane into the cytoplasm

smooth ER

a site for lipid synthesis and participates in detoxification of chemicals within cells.

golgi apparatus or golgi complex

consists of closely packed stacks of curved, membrane-bound sacs

golgi apparatus

It collects, modifies, packages, and distributes proteins and lipids manufactured by the ER.

vesicle

a small, membrane-bound sac that transports or stores materials within cells.

secretory vesicles

pinch off from the Golgi apparatus and move to the cell membrane

lysosome

are membrane-bound vesicles formed from the Golgi apparatus

lysosome

They contain a variety of enzymes that function as intracellular digestive systems.

pompe disease

caused by the inability of lysosomal enzymes to break down the carbohydrate glycogen produced in certain cells.

peroxisomes

are small, membrane-bound vesicles containing enzymes that break down fatty acids, amino acids, and hydrogen peroxide

hydrogen peroxide

a by-product of fatty acid and amino acid breakdown and can be toxic to a cell.

mitochondria

are small organelles with inner and outer membranes separated by a space

cristae

folds of the mitochondria which project into the interior of the mitochondria

mitochondrial matrix

the material within the inner membrane of the mitochondria which contains enzyme and mitochondrial DNA

mitochondria

the major sites of adenosine triphosphate (ATP) production within cells.

cytoskeleton

internal framework of the cell.

cytoskeleton

It consists of protein structures that support the cell, hold organelles in place, and enable the cell to change shape.

microtubules, microfilaments, and intermediate filaments

protein structure that make up the cytoskeleton

microtubules

are hollow structures formed from protein subunits

microtubules

perform a variety of roles, including helping to support the cytoplasm of cells, assisting in cell division, and forming essential components of certain organelles, such as cilia and flagella.

microfilaments

are small fibrils formed from protein subunits that structurally support the cytoplasm, determining cell shape.

intermediate filaments

fibrils formed from protein subunits that are smaller in diameter than microtubules but larger in diameter than microfilaments.

centrosome

a specialized area of cytoplasm close to the nucleus where microtubule formation occurs.

centrioles

a small, cylindrical organelle composed of microtubules organized into nine triplets; each triplet consists of three parallel microtubules joined together

cilia

project from the surface of cells

flagella

have a structure similar to that of cilia but are much longer, and they usually occur only one per cell.

transcription and translation

steps of gene expression

microvilli

specialized extensions of the cell membrane that are supported by microfilaments

gene expression

the process by which information stored in the genes of DNA molecules directs the manufacture of the various proteins of our cells.

transcription

During this process information stored in a region of the DNA is used to produce a complementary RNA molecule

messenger RNA (mRNA)

what does the transcription process produce?