Lecture exam two (3.1 Concepts of Cellular Structure, 3.2 The Cell Surface)

This term refers to the study of cells

Cytology

True or false : Cell theory states that all living organisms are made of one or more cells

True (cell theory)

These are the basic structural and functional units of all living organisms

Cells (cell theory)

True or false : All activities of an organism stem from activities of its constituent cells

True (cell theory)

All cells arise from _____________ (cell theory)

Pre-existing

The size of cell is limited by its relationship between ____________ and _______________.

Volume, surface area

This is why a cell who is too large cannot properly support itself

Molecules cannot diffuse quick enough to support the cells metabolism

This term refers to the fluid between the nucleus and surface membrane of a cell

Cytoplasm

This structure made of lipids and proteins surrounds the cell

Plasma membrane

This is a supportive framework of protein filaments and tubules within a cell

Cytoskeleton

These are diverse structures that preform various metabolic tasks for cells

Organelles

This term refers to foreign matter of cell products within a cell

Inclusions

Cells maintain order partly by ______________ their components in the organelles

Compartmentalizing

Cell organelles, cytoskeleton, and inclusions are embedded within this clear fluid

Cytosol

This term refers to fluids not contained in the cells

Extracellular fluids (ECF)

This term refers to fluids located within the cell

Intracellular fluids (ICF)

These are the three main functions of the plasma membrane

(1) Defines boundaries of cells

(2) Governs interactions between cells

(3) Controls passage of materials in and out of cells

Typically about 98% of the membrane molecules are __________, and about 75% of those are ______________.

Lipids, phospholipids

This is the main reason why phospholipids of a plasma membrane drift laterally from place to place

Keeps the membrane fluid

These molecules constitute about 20% of the membrane lipids and makes them membrane more stiff by interacting with phospholipids

Cholesterol

These molecules make up about 5% of the membrane lipids and contribute to the membranes glycocalyx coat

Glycolipids

Of proteins only account for about 2% of the molecules of the plasma membrane, why do they account for almost 50% of the membranes total weight?

The proteins are much larger than the lipids

These are the two classes of membrane proteins

(1) transmembrane

(2) peripheral

This class of membrane proteins pass completely through the phospholipids bilayer (protrude on both sides)

Transmembrane

This class of membrane proteins adhere to the inner or outer face of the membrane

Peripheral proteins

These are passages that allow water and other hydrophilic solutes to move through the plasma membrane

Channel proteins

These are the two types of channel proteins

Leak channels and gated channels

These are the three different types of gated protein channels

Ligand gated channels, voltage gated channels, and mechanical gated channels

These are the transmembrane proteins that bind to molecules and transfer them to the other side of the plasma membrane

Carriers

_____________ contributes to the glycocalyx which acts like an _______________ that enables immune systems to tell which cells belong to one's body and which are foreign invaders

Glycoproteins, identification tag

Cells use these proteins to adhere to one another and to extracellular material

Cell adhesion molecules (CAMs)

True or false : Cells can survive snd grow normally on their own when they are not linked to extracellular material

False

This term refers to a chemical that is produced as a result of a messenger binding to a membrane receptor triggering a metabolic pathway within the cell

Secondary messenger

Receptors, within secondary messenger systems, are liked to these proteins on the intracellular side of a cell membrane

G proteins

G proteins get their energy from this compound

GTP (Guanosine triphosphate)

When activated by the membrane receptor, a _____________ relays the signal to another membrane protein called _____________.

G protein, adenylate cyclase

_________________ removes two phosphate groups from ATP converting into the second messenger ______________.

Adenylate cyclase, cyclic AMP (cAMP)

Cyclic AMP activates cytoplasmic enzymes called _________ which adds ____________ groups to other enzymes (Activating and deactivating them)

Kinases, phosphate

This term refers to the fuzzy coat external to the plasma membrane on all animals cells

Glycocalyx

These are extensions of the plasma membrane that primarily serve to increase a cell's surface area

Microvilli

These extensions of a cells surface are best developed in cells specialized for absorption

Microvilli

This region of a cell refers to the dense area of microvilli

brush border

These are hairlike processes that mainly function as the cells "antenna" for monitoring nearby conditions

Cilia

Motile Cilia beat freely within a layer of __________ at the cell surface since they cannot beat freely when embedded in sticky mucus

Saline

_____________ in the apical plasma membrane produce a ______________ layer by pumping Cl- into the extracellular fluid.

Chloride, saline

The structural basis for ciliary movement is a core called the __________, which consists of an array of thin protein cylinders called _____________. (9+2 structure)

Axoneme, microtubules

True or False : The only functional flagellum in humans is the whiplike tail of sperm

True

These are cytoplasm-filled extensions of the cell that change continually

Pseudopods