Module 4 Flashcards
The ____ is the basic unit of all living things.
cell
_______ _____ are complex cells with a membrane bound nucleus and subcellular structures (organelles).
Eukaryotic cells
All fungi, plant, and animals are ______.
eukaryotes
_______ ______ are simple cells and most are unicellular.
Prokaryotic cells
_____ includes bacteria and don’t have a true nucleus.
Prokaryotes
The _____ _____ is a covering that regulates what comes into or leaves form the cell.
plasma membrane
The _____ is a mixture of water, salts, proteins, and organelles.
cytoplasm
The ____ is the control center of the cell. DNA and RNA are made here.
nucleus
What are the 3 main parts of eukaryotic cells?
- plasma membrane
- cytoplasm
- nucleus
The _____ _____ is also called “membrane” or “plasmslemma”.
plasma membrane
The ______ is a gelatin-like substance, plus structural fibers and organelles (but not the nucleus)
cytoplasm
The ____ contains the genetic library for the cell.
nucleus
The _____ _____ covers and protects the cell, controls what goes in and comes out, links to other cells, tells other cells who it is (flies a flag).
plasma membrane
The _______ gives it’s cell shape, contains structural (cytoskeletal) proteins, comprised of organelles (except nucleus) and cytosol.
cytoplasm
The ______ is where the genetic information is stored (the library with cookbooks entitled “How to Make a New Cell”, “How to Make the Proteins You Need”, etc…
nucleus
_____ is the genetic material that must be reproduced and read without error, and is generally never altered or destroyed.
DNA
_____ is made in the nucleus and exported into the cytoplasm, where it carries out its work: making proteins.
RNA
The new model for the cell membrane, which cam to be called the ______-_______ ______ features a lipid “sea” with protein “icebergs” floating in it and proteins which are integral or peripheral.
fluid-mosaic model
The lipids in the plasma membrane consist of ______ or ______ heads and ______ or ________ tails.
polar / hydrophillic heads;
non-polar / hydrophobic tails
_____ means embedded in bilayer, go from one side to the other.
Integral
_____ means it is associated with the inside or outside of the cell.
Peripheral
If the peripheral is _____ the cell, it links the cytoskeleton to the membrane.
inside
If the peripheral is ______ the cell, it links the cell to connective tissue or to other cells.
outside
_____ _____ ______ are loosely associated with the cell membrane and lie either completely on the outside or completely on the inside of the cell.
Peripheral membrane proteins
______ (________) ______ span the cell membrane from outside to inside the cell.
Integral (transmembrane) proteins
_______ tells us how easily a substance can cross the plasma membrane.
Permeability
______ ______ is what defines a cell
Differential permeability
What is the rule of thumb regarding selectively permeable?
small, neutrally charged, lipid-soluble substance can pass without assistance.
What are the 6 functional classes of membrane proteins?
- ion channels
- carriers
- receptors
- enzymes
- linkers
- cell identity markers
____ _____ are integral and forms a pore through which a specific ion can flow to get across the membrane.
Ion channels
____ are integral and transports a specific substance across the membrane by undergoing a change in shape. These are also known as transporters.
Carriers
_____ are integral and recognizes specific ligand and alters cell’s function in some way.
Receptors
_____ are integral and peripheral and catalyzes a reaction inside or outside the cell (depending on which direction the active site faces).
Enzymes
_____ are integral and peripheral and anchors filaments inside and outside the plasma membrane, providing structural stability and shape for the cell.
Linkers
___ ____ _____ are glycoprotein and distinguishes your cells from anyone else’s (unless you are an identical twin). An important class of such markers are the major histocompatibility (MHC) proteins.
Cell identity markers
The non-polar tails of lipid molecules prevent charged molecules, like ions, from crossing the cell membrane. ____ ____ allow ions to pass DOWN their concentration gradient (high to low). Some are open all the time, others are gated (open and close on demand).
Ion channels
Protein _____ can be transporters or pumps. Many molecules that cannot cross the cell membrane are “ferried”. This can occur up or down the concentration gradient. If it occurs against the gradient, energy is required. Energy comes from ATP and other molecules that run down their concentration gradient.
carriers
The signaling molecule that binds to the receptor is called a ______.
ligand
The process by which a signal outside the cell is transformed into a charge inside the cell is called _____ ______.
signal transduction
_______ signals outside the cell can affect activities inside the cell. The cell uses these to detect an extracellular signal and transduce it to an intracellular signal.
Receptors
Enzymes can’t and don’t change the energy profile of the reaction, but instead lower the ______ ______.
activation energy
_______ are proteins that catalyze (speed up) chemical reactions. The ones on the cell surface catalyze chemical reactions there.
Enzymes
______ link intracellular and extracellular structures. The internal structure of the cell must be connected to the connective tissues outside the cell. They join proteins inside and outside the cell.
Linkers
Most cell markers consist of a complex, branched sugar polymer attached to a transmembrane protein. This combination is called a _______.
glycoprotein
____ _____ are a way to identify cells that belong to you, and what organ they belong to. Sugars connected to proteins are commonly used as “flags”.
Cell markers
______ transport moves substance “downhill” or “with” a gradient (high to low) and does not require energy.
Passive
_____ diffusion and _____ diffusion is the movement of solutes.
Simple and facilitated
_____ is the movement of solvent.
osmosis
When both solutes and solvents are being moved, it is referred to as _______.
filtration
Molecules in a liquid or gaseous medium tend to spread themselves out evenly throughout the volume of the container. We call this _______.
diffusion
______ diffusion is used to move substances such as glucose and various ions DOWN their concentration gradients.
Facilitated
_____ diffusion allows molecules in a gas or liquid to move around. The warmer the temperature, the more movement. The smaller the molecule, the more movement. Over time, the concentration of the substance will become equal in all parts of the system. It is the random motion of small particles in a solution (Brownian motion).
Simple
Facilitated diffusion uses protein ____ or ____ in the cell membrane to facilitate the diffusion.
carriers or channels
When we combine diffusion of water with a semi-permeable membrane, we get _____.
osmosis
Osmosis is the term that describes the diffusion of solvents across a _____-________ membrane.
semi-permeable
The ______ _______ is the pressure required to nullify the movement of water through the membrane.
osmotic pressure
______ describes the concentration of solutes and is a measure of the effective osmotic pressure.
Tonicity
A _______ solution = high salt concentration = low water concentration.
Hypertonic
A ______ solution = low salt concentration = high water concentration.
hypotonic
An _____ solution = no net movement of water. The water concentration is the same inside and outside the cell.
isotonic
In ____ solutions, the concentration of solutes is lower outside the cell than inside.
hypotonic
In ______ solutions, the concentration of solutes is higher outside the cell than inside.
hypertonic
When red blood cells shrink in a hypertonic solution, we say they _____: they take on a spiny shape, which is not good if the RBC needs to slide easily through blood vessels.
crenate
The medium - pure water - has fewer solutes than the inside of cells. Therefore, the medium is _______ to the cells and the cells swell and burst.
hypotonic
The medium - 0.85% salt water - has the same number of particles in the solution as the inside of the cells. Therefore, the medium is _______ to the cells. They neither shrink nor burst.
isotonic
The medium - 3% salt water - has more particles in the solution than inside the cells. Therefore, the medium is _______ to the cells and the cells lose water and shrink.
hypertonic
______ is another type of passive transport. Solutes and colloids pass through a barrier based on size.
Filtration
Each filtration medium (for example, filter paper in a coffee maker) has a “_____ _____”.
pore size
_____ sorts particles based on size.
Filtration
_____ transport moves substances “uphill” or “against” its concentration gradient (low to high), requires energy from ATP (directly or indirectly). It’s energy sources are ATP or pre-existing storage of energy in a concentration gradient (potential energy).
Active
_____ ______ transport is when molecules are moved against their concentration gradient (low to high), energy is required, ATP or existing ionic gradient are energy sources.
Primary Active
The sodium / potassium pump is _____, since 3 positive charges are pumped out for every 2 allowed in.
electrogenic
______ ______ transport involves two types of carrier proteins, symporters and antiporters.
Secondary active
In an ______ system, two ions move in opposite directions.
antiport
In a ______ system, a molecule and an ion move in the same direction.
symport
In ______ active transport, we use the energy stored in the sodium concentration gradient established by primary active transport to move other solutes against their gradient.
secondary
Active transport uses _______ and _______ to take in and discard things needed or not needed by the cell.
endocytosis; exocytosis
During ______, the cell surface proteins (receptors) can bind molecules the cell wants to take in. After the material binds to the receptor, it is taken into the cell. This is a type of vesicluar transport.
endocytosis
In _____-_____ _____, cell surface proteins (receptor proteins) bind a substance of interest, and then signal the cell to begin the process of pinching off a vesicle.
receptor-mediated endocytosis
_____ and _____ are a type of endocytosis.
phagocytosis and pinocytosis
______ is an important defense of the body against invaders. When invaders are detected, specialized white blood cells surround and kill the invading cells.
Phagocytosis
_______ is the cell’s way of eating things. It is a specific form of endocytosis.
Phagocytosis
______ is akin to phagocytosis, but is used to bring liquids into the cell.
Pinocytosis
Pinocytosis is also called ____-____ _____.
bulk-phase endocytosis
In _______, the cell makes a pit, then seals it. In the process, a vesicleful of liquid is incorporated into the cell.
pinocytosis
_______ is like phagocytosis, but for liquids instead of solids. The cell forms a pit, then seals it, “swallowing” a tiny ball of liquid. It is non-specific.
Pinocytosis
______ is used to send materials out of the cell in bulk.
Exocytosis
______ is an active process which requires ATP for energy. It is a type of vesicular transport. It’s like endocytosis but in reverse.
Exocytosis
Recall that cells “fly a flag” with cell surface markers. These markers are placed on the cell membrane by ______.
exocytosis
Think of the _____ as a fruitcake because it is comprised of a soluble part (cytosol) plus large, semi-independent parts (organelles).
cytoplasm
_____ is made up of water, solutes, suspended particles, lipid droplets and glycogen granules.
Cytosol
_______is the solvent (water) and solutes (salts and dissolved proteins) that make up the soluble part of the cytoplasm (it’s the cake part of a fruitcake).
Cytosol
Cytoplasm is the cytosol plus ______. The ______ are the fruits and nuts in the fruitcake.
organelles (for both)
The business of the cell is carried out by the _______.
organelles
Just like the skeleton gives the body a shape and structural stability, the _______ gives the cell shape and structural ability.
cytoskeleton
What are the 5 main divisions of organelle function?
- structural integrity
- motility
- synthesis
- storage and digestion
- energy production
______ are specialized structures with characteristic shapes. Each one has specific functions.
Organelles
_______ is a network of three types of protein filaments: microfilaments, intermediate filaments, and microtubules. It maintains the shape and general organization of cellular contents; responsible for cellular movements.
Cytoskeleton
______ is a pair of centrioles plus pericentriolar material. The pericentriolar material contains tubulins, which are used for growth of the mitotic spindle and microtubule formation.
Centrosome
____ and _____ are the motile cell surface projections that contain 20 microtubules and a basal body.
Cilia and flagella
_____ move fluids over a cell’s surface.
Cilia
_____ move an entire cell.
Flagella
______ is composed of two subunits containing ribosomal RNA and proteins; may be free in cytosol or attached to rough ER. Protein synthesis.
Ribosome
_____ _____ (___) is a membranous network of flattened sacs or tubules.
Endoplasmic reticulum (ER)
_____ ____ is covered by ribosomes and is attached to the nuclear envelope. It synthesizes glycoproteins and phospholipids that are transferred to cellular organelles, inserted into the plasma membrane, or secreted during exocytosis.
Rough ER
_____ _____ lacks ribosomes. It synthesizes fatty acids and steroids; inactivates or detoxifies drugs; removes phosphate group from glucose-6-phosphate; and stores and releases calcium ions in muscle cells.
Smooth ER
_____ _____ consists of 3 - 20 flattened membraneous sacs called cisternae; structurally and functionally divided into entry (cis) face, medial cisternae, and exit (trans) face. Entry (cis) face accepts proteins from rough ER; medial cisternae form glycoproteins, glycolipids, and lipoproteins; exit (trans) face modifies the molecules further, then sorts and packages them for transport to their destinations.
Golgi apparatus
