Unit 4 PC: Cell Communication Flashcards
How do cells communicate with other cells over short distances?
cells use local regulators to communicate across short distances
How do cells communicate with other cells over long distances?
cells can release chemical signals with the ability to travel over long distances to target cells of other types
How is the process of distance communication different from the process of communicating during cell-cell contact?
structural modifications of the cell membrane and cell wall allow cells to send chemical signals directly into adjacent cells.
What is a signal transduction pathway?
a signal transduction pathway is the binding of signaling molecules to receptors located on the cell surface or inside the cell that trigger events inside the cell, to invoke a response.
Why do cells use signal transduction pathways?
cells use signal transduction pathways to link signal reception with cellular response (like growth, secretion, and gene expression).
How does a signal transduction pathway begin?
A signal transduction pathway begins when a receptor/ligand binds to external receptors or an intracellular receptor.
What is the role of protein modification in signal transduction pathways?
The role of protein modification in signal transduction pathways is to cause a conformational shape change due to the ligand binding. This change elicits and intracellular response, which causes a second messenger to be activated.
What is the role of phosphorylation cascades in signal transduction pathways?
a phosphorylation cascade is a signaling pathway where one enzyme phosphorylates another, causing an amplification of the reaction, and leading to the phosphorylation of thousands of proteins.
What role does the environment play in eliciting cellular responses?
the environment is not static and organisms need to respond to changes in the environment. The ability to respond to stimuli is characteristic of life and necessary for survival.
How are signal transduction pathways used to influence cellular responses when there are changes in the environment
Signal transduction pathways are used to influence cellular responses when the environment changes. Transduction pathways can regulate gene expression in response to changes in the environment or lead to apoptosis.
How can mutations in the receptor protein or any component of the signaling pathway affect the transduction of a signal
a mutation that alters the ligand/receptor specificity can lead to incompatibility, which can alter the signal transduction pathway. The receptor will not undergo proper conformational shape change, resulting in an inactive internal pathway.
How can chemicals activate a pathway?
chemicals can activate a signal transduction pathway, which can lead to amplification of the pathway.
How can chemicals inhibit a pathway?
chemicals can inhibit a signal transduction pathway, which can lead to the pathway not occurring
What are feedback mechanisms?
Feedback mechanisms are processes used to main homeostasis by increasing or decreasing a cellular response to an event.
How does negative feedback maintain homeostasis?
negative feedback mechanisms maintain homeostasis for a particular condition by regulating physiological processes
