BIO 360 - Exam 1 - Chapter 3 Outline Flashcards
(35 cards)
The ______ cavity {cranium, skull} contains the brain, our primary control center.
The ______ cavity is bounded by the spine and ribs on top and sides, with the muscular diaphragm forming the floor.
The ______ contains the heart, which is enclosed in a membranous pericardial sac {peri-,heart}, and the two lungs, enclosed in separate pleural sacs.
cranial / thoracic / thorax
The interior of any hollow organ is called its ______.
lumen
Cancer is a condition in which a small group of cells starts to divide uncontrollably and fails to differentiate into specialized cell types. Cancerous cells that originate in one tissue can escape from that tissue and spread to other organs through the circulatory system and the lymph vessels, a process known as ______.
metastasis
What are the two main fluid compartments of the cell body?
(1) the extracellular fluid (ECF) outside the cells
(2) the intracellular fluid (ICF) within the cells
The word ______ may apply either to a tissue or to a phospholipid-protein boundary layer.
membrane
The general functions of the cell membrane include
(1) Physical isolation. The cell membrane is a physical barrier that separates intracellular fluid inside the cell from the surrounding extracellular fluid.
(2) Regulation of exchange with the environment. The cell membrane controls the entry of ions and nutrients into the cell, the elimination of cellular wastes, and the release of products from the cell.
(3) Communication between the cell and its environment. The cell membrane contains proteins that enable the cell to recognize and respond to molecules or to changes in its external environment. Any alteration in the cell membrane may affect the cell’s activities.
(4) Structural support. Proteins in the cell membrane hold the cytoskeleton, the cell’s interior structural scaffolding, in place to maintain cell shape. Membrane proteins also create specialized junctions between adjacent cells or between cells and the extracellular matrix {extra-, outside}, which is extracellular material that is synthesized and secreted by the cells. Cell-cell and cell-matrix junctions stabilize the structure of tissues.
______ is the process by which a cell releases a substance into the extracellular space.
Secretion
All biological membranes consist of a combination of ______ and ______ plus a small amount of carbohydrate.
lipids and proteins
Three main types of lipids make up the cell membrane:
phospholipids, sphingolipids, and cholesterol.
When placed in an aqueous solution, phospholipids orient themselves…
so that the polar heads of the molecules interact with the water molecules while the nonpolar fatty acid tails “hide” by putting the polar heads between themselves and the water.
______ or ______ of proteins is one way cells alter protein function.
Phosphorylation or dephosphorylation
The 20–25 amino acids in the protein chain segments that pass through the bilayer are ______. This allows those amino acids to create strong ______ interactions with the lipid tails of the membrane ______, holding them tightly in place.
nonpolar / noncovalent / phospholipids
______ on the cell surface play a key role in the body’s immune response. For example, the ABO blood groups are determined by the number and composition of sugars attached to membrane sphingolipids.
Glycoproteins
The cytoplasm includes all material inside the cell membrane except for the nucleus. The cytoplasm has four components:
(1) Cytosol or intracellular fluid: The cytosol contains dissolved nutrients and proteins, ions, and waste products. The other components of the cytoplasm—inclusions, fibers, and organelles—are suspended in the cytosol.
(2) Inclusions are particles of insoluble materials. Some are stored nutrients. Others are responsible for specific cell functions. These structures are sometimes called the nonmembranous organelles.
(3) Insoluble protein fibers form the cell’s internal support system, or cytoskeleton.
(4) Organelles—“little organs”—are membrane-bound compartments that play specific roles in the overall function of the cell. For example, the organelles called mitochondria (singular, mitochondrion) generate most of the cell’s ATP, and the organelles called lysosomes act as the digestive system of the cell.
The insoluble protein fibers of the cell have two general purposes:
structural support and movement.
The cytoskeleton has at least five important functions:
(1) Cell shape.
(2) Internal organization. Cytoskeletal fibers stabilize the positions of organelles.
(3) Intracellular transport. The cytoskeleton helps transport materials into the cell and within the cytoplasm by serving as an intracellular “railroad track” for moving organelles.
(4) Assembly of cells into tissues.
(5) Movement. The cytoskeleton helps cells move.
______ ______ are proteins that convert stored energy into directed movement.
Motor proteins
Three groups of motor proteins are associated with the cytoskeleton: ______, ______, and ______. All three groups use energy stored in ATP to propel themselves along cytoskeleton fibers.
myosins, kinesins, and dyneins -
The second compartment inside a mitochondrion is the intermembrane space, which lies between the outer and inner mitochondrial membranes.
What is the role of the intermembrane space?
Mitochondrial ATP production - the number of mitochondria in a cell is directly related to the cell’s energy needs.
For example, skeletal muscle cells, which use a lot of energy, have many more mitochondria than less active cells, such as adipose (fat) cells.
How does mitochondria replicate?
Budding - during which small daughter mitochondria pinch off from an enlarged parent.
For instance, exercising muscle cells that experience increased energy demands over a period of time may meet the demand for more ATP by increasing the number of mitochondria in their cytoplasm.
What is the endoplasmic reticulum (ER)?
What are the three major functions?
A network of interconnected membrane tubes.
Synthesis, storage, and transport of biomolecules.
The ______ ______ ______ is the main site of protein synthesis.
rough endoplasmic reticulum
The ______ ______ ______ lacks attached ribosomes and is the main site for the synthesis of fatty acids, steroids, and lipids
smooth endoplasmic reticulum
The ______ ______ receives proteins made on the rough ER, modifies them, and packages them into the vesicles.
Golgi apparatus