HA&P: Chapter 3 - Part 2

What are found on almost every cell in the body and its key roles are in embryonic development and would repair and in immunity?

Cell adhesion molecules (CAMs)

These are a huge and diverse group of integral proteins that serve as binding sites and it functions in contact signaling?

Membrane receptors

What kind of signaling is where the cells come together and touch, cells recognize one another, and is important for normal development and immunity?

Contact signaling

What kind of signaling has the process in which a ligand (chemical messenger) binds a specific receptor and initiates a response?

Chemical signaling

What do the ligands include?

Neurotransmitters (nervous system signals), Hormones (endocrine system signals), & Paracrines (chemicals that act locally and are rapidly destroyed)

What exerts their effect indirectly through a G protein, which is a regulatory molecule that acts as a middleman or relay to activate a membrane-bound enzyme or ion channel?

G protein-coupled receptors

With the G protein-coupled receptors, it generates one or more intracellular chemical signals which can be called what, that connects the plasma membrane events to the internal metabolic machinery of the cell?

Second messengers

What are the two important second messengers, which they activate protein kinase enzymes and transfer phosphate groups from ATP to other proteins?

Cyclic AMP & Ionic calcium

What are the 6 steps in G proteins?

1. Ligand binds to the receptor

2. The activated receptor binds to a G protein and activates it

3. Activated G protein activates (or inactivates) an effector protein by causing its shape to change

4. Activated effector enzymes catalyze reactions that produce 2nd messengers in the cell

5. Second messengers activate other enzymes or ion channels

6. Kinase enzymes activate other enzymes

What is the cellular material between the plasma membrane and the nucleus and is the site of most cellular activities?

Cytoplasm

What is the viscous, semitransparent fluid in which the other cytoplasmic elements are suspended, is a complex mixture with properties of both a colloid and a true solution, and water is dissolved in this?

Cytosol

What are chemical substances that may or may not be present, depending on the cell type and one example it has is including stored nutrients?

Inclusions

What are the metabolic machinery of the cell and with each type of this it carries out a specific functions for the cell like proteins and generate ATP?

Organelles

What do the membranes enable that maintains an internal environment different from that of the surrounding cytosol?

Membranous organelles

What are the typically threadlike or lozenge-shaped membranous organelles, they squirm, elongate, and change shape almost continuously, they are the power plants of a cell that provides most of its ATP supply, and they contain their own DNA, RNA, and ribosomes?

Mitochondria

In the outer membrane is smooth and featureless, but in the inner membrane it folds inwards, forming what that protrudes into the matrix, the gel-like substance within the mitochondrion?

Cristae

These are small, dark-staining granules composed of proteins and a variety of RNAs called ribosomal RNAs and they are the sites of protein synthesis?

Ribosomes

What kind of ribosomes float freely in the cytosol and they make soluble proteins that function in the cytosol?

Free ribosomes

What kind of ribosomes are attached to membranes that form the rough endoplasmic reticulum and they synthesize proteins into cell membranes?

Membrane-bound ribosomes

This is an extensive system of interconnected tubes and parallel sacs called cisterns, and are continuous with the outer nuclear membrane and accounts for half of the cell’s membranes?

Endoplasmic reticulum (ER)

What kind of ER, is called “rough”, the ribosomes manufacture all proteins secrete from cells, are abundant and well developed in most secretory cells, and is also the cell’s “membrane factory” where integral proteins and phospholipids that form part of all cellular membranes are manufactured?

Rough ER

What kind of ER is continuous with the Rough ER and consists of tubules arranged in a looping network and its enzymes play no role in protein synthesis, metabolizes lipids, synthesize cholesterol and phospholipids, detoxify drugs, and store calcium ions?

Smooth ER

This organelle consists of stacked and flattened membranous sacs, associated with swarms of tiny membranous vesicles, is the principal “traffic director” for cellular proteins, and its function is to modify, concentrate, and package the proteins and lipids?

Golgi Apparatus

This organelle resembles small lysosomes, are spherical membranous sacs containing oxidases and catalases, and are numerous in liver and kidney cells, and play a role in energy metabolism?

Peroxisomes

With oxidases that use molecular oxygen to detoxify harmful substance, it has the function to neutralize this chemical that is unpaired to electrons that can scramble the structure of biological molecules?

Free radicals

What organelle are spherical membranous organelles containing activated hydrolytic enzymes, are large phagocytes, digest almost all kinds of biological molecules that work best in acidic conditions which can be called acid hydrolases?

Lysosomes

What are the two important functions of the lysosomal membrane?

1. Contains H+ “pumps” which are ATPases that gather hydrogen ions from the surrounding cytosol to maintain the organelle’s acidic pH

2. Retains the dangerous lysosomal enzymes while permitting the final products of digestion to escape so that they can be used by the cell or excreted

What process is done when the lysosomes rupture, and the cell digests itself?

Autolysis

What disease in the lysosomes lack an enzyme needed to break down a specific glycolipid in nerve cell membranes?

Tay-Sachs disease

This is a system or organelles that work together to produce, degrade, store, and export biological molecules, and degrade potentially harmful substances, it also includes the ER, golgi apparatus, secretory vesicles, and lysosomes?

Endomembrane system

These are “cell skeletons”, which are a elaborate network of rods running through the cytosol and hundreds of accessory proteins that link these rods to other cell structures, and acts as a cell’s “bones,” “muscles,” and “ligaments” by supporting cellular structures and provides the machinery to generate various cell movements?

Cytoskeleton

What cytoskeleton is the thinnest element, that are semiflexible strands of the protein actin and are involved in cell motility or changes in cell shape, and as they break down and re-form, the actin filaments push or pull on the plasma membrane, changing the cell’s shape?

Microfilaments

What cytoskeleton are tough, insoluble protein fibers that resemble woven ropes, are made of twisted units of tetramer fibrils, are the most stable and permanent of the cytoskeletal elements and resist tension, and attach to desmosomes and act as internal cables to resist pulling forces exerted on the cell?

Intermediate filaments

What cytoskeleton are hollow tubes made of spherical protein subunits called tubulin and radiate from a small region of cytoplasm near the nucleus called the centrosome or cell center, and determine the overall shape of the cell?

Microtubules

What are the protein machines that move and reposition the organelles along the microtubules?

Motor proteins

Microtubules are anchored at one end in an inconspicuous region near the nucleus to which it can also be called a cell center and acts as a microtubule organizing center?

Centrosome

The centrosome has distinguishing marks other than a granular-looking matrix that contains this paired, that are oriented at right angles to each other and has a array of nine triplets of microtubules?

Centrioles

What organelle are whiplike, motile cellular extensions, that occur on the exposed surfaces of certain cells and with its action it moves substances in one direction across cell surfaces?

Cilia

What is formed when the microtubules “sprout” from each centriole by the exertion pressure on the plasma membrane?

Ciliary projections

These are projections formed by centrioles, but are longer than cilia, is the only flagellated cell in the human body is a sperm?

Flagella

Centrioles forming the bases of cilia and flagella can be referred to as?

Basal bodies

What pattern of the microtubules in the cilium or flagellum itself differs slightly from that of a centriole?

9+2 pattern of the microtubules

When a cilium moves, it alternates rhythmically between a propulsive a.________, as it is nearly straight and moves in an arc and a b._______ as it bends and returns to its initial position?

a. Power stroke

b. Recovery stroke

These are tiny, fingerlike extensions of the plasma membrane that project from an exposed cell surface and increase the plasma membrane surface area and are found on the surface of absorptive cells?

Microvilli

Microvilli has this bundled actin filaments that extend into a mat of actin filaments, that are near the surface of the cell?

Microvilli

This is the control center that is a gene-contain?

Nucleus

This is the presence of more than one nucleus and there are many?

Multinucleate

These are cells that cannot reproduce and live in the bloodstream for only three to four months before they deteriorate?

Anucleate

What is the nucleus bounded by, which is a double membrane barrier separated by a fluid-filled space and is selectively permeable?

Nuclear envelope

What part of the nuclear membrane is continuous with the rough ER of the cytoplasm and is studded with ribosomes on its external face?

Outer nuclear membrane

What part of the nuclear membrane is lined by the nuclear lamina, a network of lamins that maintains the shape of the nucleus and acts as a scaffold to organize DNA in the nucleus?

Inner nuclear membrane

What is the nuclear envelope is punctured by?

Nuclear pores

These are intricate complex of proteins, lines each pore, forming an aqueous transport channel and regulating entry and exit of molecules and large particles into and out of the nucleus?

Nuclear pore complex

What does the nuclear envelope enclose in which other nuclear elements are suspended and it contains dissolved salts, nutrients, and other essential solutes?

Nucleoplasm

What is within the nucleus, that are dark-staining spherical bodies where the ribosomal subunits are assembled and are not membrane bounded, and are aggregations of all of the components needed to synthesize and assemble ribosomal subunits?

Nucleoli

What do the nucleoli center around the DNA that it codes for?

Ribosomal RNA (rRNA): combine with proteins to form the two kinds of ribosomal subunits

What appears as a fine, unevenly stained network, but special techniques reveal it as a system of bumpy threads weaving through in the nucleoplasm and is composed of 30% DNA, 60% globular histone proteins, & 10% RNA?

Chromatin

What are the fundamental units of chromatin that consist of flattened disc-shaped cores or clusters of eight histone proteins connected like beads on a string by a DNA molecule?

Nucleosomes

When a cell is preparing to divide, the chromatin threads coil and condense enormously to form short, barlike bodies that can be called what and its compactness prevents the delicate chromatin strands from tangling?

Chromosomes