Biology Vocab - Chapter 7

Active Transport

Energy requiring process by which substances move across the plasma membrane against a concentration gradient

cell

Basic unit of structure and organization of all living organisms

cell theory

State that (1) organisms are made of one or more cells; (2)cells are basic unit of life; (3)and all cells come only from other cells

Cell Wall

In plants, the rigid barrier that surrounds the outside of the plasma membrane, is made of cellulose, and provide support and protect to the cell.

centriole

Organelle that plays a role in cell division and is made of microtubules

chloroplast

Double-membrane organelle that captures light energy and converts it to chemical energy through photosynthesis

cilium

Short, hairlike projection that functions in cell movement

cytoplasm

Semifluid material inside the cells plasma membrane

cytoskeleton

Supporting network of Protein fibers that provide a framework for the cell within the cytoplasm

diffusion

Net movements of particles from an area of higher concentration to an area of lower concentration

dynamic equilibrium

Condition of continuous, random movements of particle but no overall change in concentration of material

endocytosis

Energy-requiring process by which large substances from the outside environment can enter a cell

endoplasmic reticulum

Highly folded membrane system in eukaryotic cells that is the site for protein and lipid synthesis

eukaryotic cell

Unicellular organism with membrane-bound nuculeus and organelles; generally larger and more complex than a prokaryotic cells

exocytosis

Energy-requiring process by which a cell expels wastes and secretes substances at the plasma membrane

facilitated diffusion

Passive transportation of ions and small molecules across the plasma membrane by transport proteins

flagellum

Long, tail-like projection with a whiplike motion that helps a cell move through a watery environment

Fluid Mosaic Model

A plasma membrane with components consistently in motion, sliding past one another within the lipid bilayer

Golgi Apparatus

Flattened stack of tubular membranes that modifies, sorts, and packages proteins into vesicles and transports them to other organelles or out of the cell

hypertonic solution

The concentration of the solute outside of the cell is higher than the Inside

hypotonic solution

A solution that has a lower concentration of solute outside then inside the cell, causing water to flow into the cell by osmosis

isotonic solution

A solution With the same concentration of water and solutes as inside a cell, resulting in the cell retaining its normal shape because there's no net movement of water

lysosome

Vesicle that uses enzymes to digest excess or worn-out cellular substances

mitochondrion

Membrane bound organelle that converts fuel into energy that is available to the rest of the cell

nucleolus

The site of ribosom production within the nucleus of eukaryotic cells

nucleus

Center of an atom; contains neutrons and protons. in eukaryotic cells, the central membrane-bound organelle that manages cellular functions and contains DNA

organelle

Specialized internal cell structure that carries out specific cell functions such as protein synthesis and energy transformation

osmosis

Diffusion of water across a selectively premeable membrane

phospholipid bilayer

Plasma membrane layers composed of phospholipid molecules arranged with polar heads facing the outside of non-polar tails facing the inside

plasma membrane

Flexible, selectively premeable boundary that helps control what enters and leaves the cell

prokaryotic cell

Microscopic, unicellular organism without a nucleus or other membrane-bound organelles

ribosome

Simple cell organelle that helps manufacture proteins

selective permeability

Property of the plasma membrane that allows it to control movement of substances Into or out of the cell

transport protein

Protein that moves substances or wastes through the plasma membrane

vacuole

Membrane-bound vesicle for temporary storage of materials such as food, enzymes, and wastes