chapter 7 the discovery of cells
A system of membranes that modifies and packages proteins for export by the cell
golgi apparatus
Found inside the nucleus and produces ribosomes
nucleolus
central membrane bound organelle that manages or controls cellular functions
nucleus
Structures specialized to perform distinct processes within a cell.
organelles
the diffusion of water across a selectively permeable membrane
osmosis
compare the number of vacuoles in plant cells and animal cells
plant cells have one large vacuole and animal cells have a few small vacuoles.
Organisms with no membrane bound structures; bacteria are one example
prokaryotes
the basic units of living organisms
cell
one of the fundamental ideas of modern biology and includes three key principles
cell theory
A rigid structure that surrounds the cell membrane and provides support to the cell
cell wall
List the three principles of the cell theory
1. All living organisms are composed of one or more cells. 2. Cells are the basic unit of structure and organization of all living organisms. 3. Cells are made up of preexisting cells.
An organelle found in plant and algae cells where photosynthesis occurs
chloroplast
compare and contrast hypotonic and hypertonic solutions
.Hypotonic solutions are solutions where the water enters the cell by osmosis, and hypertonic solutions are solutions where water leaves the cell by osmosis.
What type of cells have plasma membranes? Prokaryotic or eukaryotic.
Both
Has a glycerol backbone and two fatty acid chains and a phosphate group.
Phospholipid
A selectively-permeable phospholipid bilayer forming the boundary of the cells and their environment
Plasma membrane
If a cell synthesizes large quantities of protein molecules, which organelles might be numerous in that cell?
Ribosomes
Describe the structure of a phospholipid use the terms polar and nonpolar in your answer
The phospholipids are arranged in such a way that the polar heads can be closer to the water molecules and the nonpolar tails can be farthest away from the water molecules. This creates a barrier that is polar at its surface and nonpolar in the middle.
How are the highly folded membranes an advantage for the functions of cellular parts?
The pleats and folds provide a large amount of surface area where cellular functions can take place.
the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy.
active transport
Why is the structure of the plaza membrane referred to as a fluid Mosaic
because in the plasma membrane the phospholipids in the bilayer create a "sea" in which the molecules can float. This concept is the basis for the fluid mosaic model.
which cells are eukaryotic cells, plant or animal?
both
Tiny strands inside the nucleus that contain the instructions for directing the cell's functions (genetic material)
chromatin
Hairlike projections that extend from the plasma membrane and are used for locomotion
cilia
A jellylike fluid inside the cell in which the organelles are suspended
cytoplasm
A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement
cytoskeleton
the net movement of particles from an area where there are many particles of the substance to an area where there are fewer particles of the substance.
diffusion
continuous movement, but no overall change
dynamic equilibrium
the taking in of matter by a living cell by invagination of its membrane to form a vacuole.
endocytosis
What is endocytosis and what is exocytosis? Compare and Contrast.
endocytosis is the taking in of matter by a living cell by invagination of its membrane to form a vacuole. exocytosis is a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.
A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids.
endoplasmic reticulum
Cells that contain internal membranes; opposite of prokaryotes most of the multicellular organisms we know
eukaryotes
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.
exocytosis
uses transport proteins to move other ions and small molecules across the plasma membrane.
facilitated diffusion
A long, whip-like filament that helps in cell motility. Many bacteria are flagellated, and sperm are flagellated.
flagella
a particular type of solution that has a greater concentration of solutes on the outside of a cell when compared with the inside of a cell.
hypertonic solution
any solution that has a lower osmotic pressure than another solution.
hypotonic solution
two solutions having the same osmotic pressure across a semipermeable membrane.
isotonic solution
A small, round cell structure containing chemicals that break down large food particles into smaller ones.
lysosome
The cytoskeleton filaments with the smallest diameter. Microfilaments are composed of the contractile protein actin. They are dynamic filaments, constantly beig made and broken down as needed, and are responsible for events such as pseudopod formation and cytokenesis during mitosis.
microfilament
Thick hollow tubes that make up the cilia, flagella, and spindle fibers.
microtubule
An organelle in eukaryotic cells that serves as the site of cellular respiration; uses oxygen to break down organic molecules and synthesize ATP
mitochondria
Describe the differences between a prokaryotic and eukaryotic cell, identify their parts
prokaryotic cells are cells without a nucleus or other membrane-bound organelles. eukaryotic cells are cells that contain a nucleus and other organelles that bound by membranes. both cells have a plasma membrane, while eukaryotic cells have a nucleus and prokaryotic cells do not.
A cell organelle constructed in the nucleolus and functioning as the site of protein synthesis in the cytoplasm; consists of rRNA and protein molecules, which make up two subunits.
ribosome
compare & contrast two types of endoplasmic reticulum
rough endoplasmic reticulum is the area of ER where ribosomes are attached and smooth endoplasmic reticulum is the area where ribosomes are not attached.
The process in which a membrane allows some molecules to pass through while keeping others out
selective permeability
what makes up the animal cell?
the animal cell is made up of a nucleus, a nucleus pore, a nucleolus, microtubule, cytoplasm, mitochondria, vacuole, vesicle, golgi apparatus, ribosomes, plasma membrane, both rough and smooth er's, lysosome, and centriole
Compare and contrast the functions of a cell wall to the functions of the plasma membrane
the cell wall is a barrier that provides support and protects the plant cell, while the plasma membrane is a flexible boundary that controls what comes in and out of the cell. the cell wall is only found in plant cells and the plasma membrane is found in all cells.
what makes up the plant cell?
the plant cell is made up of a nucleus, a nucleus pore, a nucleolus, a vacuole, a cell wall, mitochondria, chloroplast, cytoplasm, golgi apparatus, plasma membrane, ribosomes, both rough and smooth er's, and microtubule
Describe the plasma membrane and explain why it is called a bilayer structure
the plasma membrane is a special boundary that helps control what enters and leaves the cell. it's called the bilayer structure because it's composed of a phospholipid bilayer, which is two layers of phospholipids that are arranged tail-to-tail.
what are transport proteins and what do they do?
transport proteins are proteins that span the entire membrane and create tunnels through which certain substances enter and leave the cell. they move needed substances or waste materials through the plasma membrane.
Cell organelle that stores materials such as water, salts, proteins, and carbohydrates
vacuole