Chapter 7 Flashcards
Van Leeuwenhoek
A man from Holland who used a single-lens microscope to observe pond water and other things. The microscope revealed a fantastic world of tiny living organisms that seemed to be everywhere.
Hooke
An English man who used an early compound microscope to look at a nonliving thin slice of cork, a plant material. He discovered what he called cells.
Prokaryotes
Cells that do no enclose their DNA in nuclei
Eukaryotes
Cells that enclose their DNA in their nuclei
Cell Membrane
A thin flexible barrier surrounding the cell.
Cell Wall
A strong supporting layer around the membrane.
Nucleus
A large membrane-enclosed structure that contains genetic material in the form of DNA and controls many of cell’s activities.
Cytoplasm
The portion of the cell outside of the nucleus.
Nuclear Envelope
The double lipid bilayer membrane which surrounds the genetic material and nucleolus in eukaryotic cells.
Nucleolus
A small dense region where the assembly of ribosomes begins.
Chromatin
Substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones.
Chromosomes
Threadlike structures of DNA and protein that contains genetic information; in eukaryotes, chromosomes are found in the nucleus; in prokaryotes, they are found in the cytoplasm.
Cytoskeleton
A network of protein filaments that give eukaryotic cells their shape and internal organization. It also helps transport material between different parts of the cell.
Contractile Vacuoles
Large, saclike, membrane-enclosed structures that store materials like water, salts, proteins, and carbohydrates.
Vescicles
A small organelle within a cell, consisting of fluid enclosed by a lipid bilayer membrane.
Lipid Bilayer
Is what gives cell membranes a flexible structure that forms a strong barrier between the cell and it surroundings.
Solute
The component in a solution that’s dissolved in the solvent.
Solvent
The liquid in which a solute is dissolved to form a solution.
Passive Transport
The movement of material across the cell membrane without using cellular energy.
Active Transport
The movement of materials against a concentration difference. Active transport require energy.
Diffusion
When molecules move from an area of higher concentration to an area of lower concentration.
Equilibrium
When the concentration of the solute is the same throughout the solution.
Facilitated Diffusion
When certain molecules cross the membrane through specific proteins channels found in the membrane.
Osmosis
The diffusion of water through a selectively permeable membrane.
Isotonic
When the concentration of the solutions are the same on both sides of the membrane.
Hypertonic
The side of the cell with the higher concentration (above strength).
Hypotonic
The side of the cell with the lower concentration (below strength).
Osmotic Pressure
The pressure osmosis exerts on the hypertonic side of a selectively permeable membrane.
Endocytosis
Taking materials into the cell by the means of infolding, or pockets, of the cell membrane.
Phagocytosis
Large particles taken into the cell.
Pinocytosis
Taking up liquid from their environment.
Exocytosis
Vesicles fusing with the cell membrane.
Unicellular
One-celled organisms.
Multicellular
Organisms made up of many cells.
Cell Specialization
The cell performing a specific function for a larger organ or tissue.
Organ
Group of tissue working together.
Organ System
Group of organs working together to perform a specific function.
Receptor
A protein molecule usually found embedded within the plasma membrane surface of a cell that receives chemical signals from outside the cell.
Cell Theory
Cells are the basic units of structure and function in living things, All living things are composed of cells, and new cells are produced from existing cells.
