Exam 1 Flashcards
A single cell may have receptors for multiple intercellular communication molecules. (True/False)
True
All enzymes are proteins. (True/False)
True
All forms of active transport use ATP either directly or indirectly. (True/False)
True
Calcium acts as a second messenger in cells. (True/False)
True
Over what distance is diffusion efficient?
Short distances
What change in concentration is net diffusion?
From high to low concentration
Which environment does homeostasis maintain?
Extracellular Environment
What is the study of body structure called?
Anatomy
Water moves towards solutions with…
High osmotic pressure
Is flux through an ion channel or a transporter faster?
Ion Channel
Exercise increases the ability of your blood to clot should you experience mechanical trauma. This is an example of:
Feed-forward
Mechanical trauma leads to leakage of blood from blood vessels, which triggers clotting to stop blood loss. This is an example of:
Negative Feedback
What do you do to an enzymes affinity for a substrate to decrease the rate of the reaction catalyzed by that enzyme at ligand concentration below a new saturation level?
Decrease its affinity.
What forms a permeability barrier between cells?
Tight Junctions
What are the mechanism(s) for gating ion channels?
Ligand-gating
Mechanical-gating
Voltage-gating
What helps make up desmosomes?
Cadherins
Steady-state requires energy. (True/False)
True
What in the plasma membrane makes it less fluid?
Cholesterol
Why are all cells not the same even though they have the same DNA?
Cellular differentiation
What types of proteins are involved in retrograde transport in neurons?
Dyneins
What is a collection of neuronal cell bodies in the central nervous system called?
Nucleus
IP3 stimulates the release of what ion from the smooth endoplasmic reticulum?
Calcium
What enzyme does the alpha subunit of Gi bind to?
Adenylyl cyclase
What enzyme does the alpha subunit of Gq bind to?
Phospholipase C
Which organ systems are involved in homeostasis?
All except the reproductive system
Desmosomes are common in epithelial cells. (True/False)
True
Diffusion is effective over what distance?
Short
In a healthy person, all variables are always in homeostasis. (True/False)
False
If an ion channel lets potassium (39 g/mol) pass through, it must also allow sodium (23 g/mol) to pass through. (True/False)
False
Intracellular receptors are also transcription factors. (True/False)
True
Ligands are covalently bound proteins. (True/False)
False
Most proteins have multiple binding sites for ligands. (True/False)
True
Multi-step signal transduction pathways allow for amplification of the effects in the cell. (True/False)
True
Positive feedback can be used to maintain homeostasis. (True/False)
True
Reflexes happen inside a cell. (true/false)
False
Since hormones enter the blood, all cells in the body will respond to the hormone. (true/false)
False
The more solutes dissolved in a water solution, the higher the osmolarity of the solution. (true/false)
True
What is the predominant use of ATP in cells?
Phosphorylate proteins
Equilibrium or Steady-State
Which does NOT require energy to be maintained?
Equilibrium
Are there more types of Intracellular Receptors or Membrane-bound Receptors?
Intracellular Receptors
What type of osmolarity does water move towards?
Higher osmolarity
On which side are integral proteins glycosylated?
The extracellular side
What does it mean to say that epithelial cells are polar?
They have different proteins on the apical and basolateral membrane
What is the MOST SPECIFIC type of endocytosis?
Receptor-Mediated Endocytosis
What is the study of body structure called?
Anatomy
Connexins are a part of…
Gap Junctions
What does the alpha-subunit of Gq-protein bind to?
Phospholipase C
If J is positive, the net flux is from…
Outside the cell to inside the cell
What would increasing the affinity of an enzyme for a substrate do to the reaction rate?
Increase the rate of reaction at substrate concentrations below the initial saturation level
When the sodium-potassium pump is phosphorylated, what does it have a high affinity for and where are its binding sites?
High affinity for potassium
Both binding sites are facing the extracellular side
Which cell communication requires direct cell contact?
Juxtacrine communication
What are the products of the reaction catalyzed by Phospholipase C?
DAG and IP3
What enzyme is necessary for the dephosporylation of proteins?
Phosphoproteins phosphatase
What transcription factor does JAK bind to?
STAT
What can increase the rate of flux of a solute across a semipermeable membrane?
Increased surface area
Increased permiability
Positive change in concentration
What is the equation for net flux?
J = AP(Co - Ci)
What is a functional unit?
A small, repeating unit that performs the function of the organ.
