human biology chapter 3 of Sylvia s. Madera and Michael Windelspecht

plasma membrane

The membrane at the boundary of every cell that acts as a selective barrier, thereby regulating the cell's chemical composition.

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Organelles are

tiny cell structures that carry out specific functions within the cell

2 groups of bacteria that are prokaryotes

eubacteria and archaebacterial

Cytoskeleton

A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement

intermediate filaments

Threadlike proteins in the cell's cytoskeleton that are roughly twice as thick as microfilaments

actin filaments

protein fibers that play a role in cell division and shape

centrioles function

organize DNA during cell division

centrosome

microtubule organizing center

Lysosomes

An organelle containing digestive enzymes

Vesicle

A membrane bound sac that contains materials involved in transport of the cell.

Chromatin

Clusters of DNA, RNA, and proteins in the nucleus of a cell

Nucleus

Control center of the cell

Nucleolus

Makes ribosomes

Rough ER

ER that is dotted with ribosomes

Smooth ER

Makes lipids

Ribosomes

site of protein synthesis

Mitochondria

Powerhouse of the cell

polyribosome

string of ribosomes simultaneously translating regions of the same mRNA strand during protein synthesis

glycoproteins and glycolipids

Carbohydrate chains attached to proteins and lipids and identify foreign cells

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

Osmosis

movement of water molecules from high to low water concentration

hypotonic solution

A solution in which the concentration of solutes is less than that of the cell that resides in the solution, more water

Hypertonic

Having a higher concentration of solute than another solution.

osmotic pressure

the external pressure that must be applied to stop osmosis

facilitated transport

a process by which material moves down a concentration gradient (from high to low concentration) using integral membrane proteins

active transport

the movement of materials through a cell membrane using energy from lower to higher concentration.

Endocytosis

A process in which a cell engulfs extracellular material through an inward folding of its plasma membrane to make a vesicle

Phagocytosis

endocytosis of pathogens by white blood cells

Pinocytosis

endocytosis of fluid

Endocytosis

process by which a cell takes material into the cell by infolding of the cell membrane

receptor mediated endocytosis

binding of ligands to receptors triggers vesicle formation and endocytosis

Endonembrane system

series of membranous organelles that function to process materials for the cell

Genes

contains instructions for the productivity of proteins

Nucleoplasm

Fluid inside the nucleus

Nucleolus

dark region in the nucleus

nuclear envelope

layer of two membranes that surrounds the nucleus of a cell

nuclear pores

small holes in the nuclear envelope

polyribosome

A group of several ribosomes attached to, and translating, the same messenger RNA molecule.

ribosomes are made of

rRNA and protein

what's in the endonembrane system

nuclear envelope. endoplasmic reticulum, golgi apparatus, lysosomes, and vesicles

Cillia

moves mucous toward the throat

Flagella

on sperm. it helps propel sperm to the egg

collagen

resists stretching

Elastin

provides resilience

Mitochondria

Powerhouse of the cell

celular respiration

uses O2 and gives off CO2