Signal Transduction Pathways and Effects

The video tutorial explains signal transduction pathways, starting with basic concepts and moving to complex examples like the Wnt, RTK, and cortisol pathways. It highlights the importance of these pathways in cellular communication and their relevance to the AP Biology curriculum. The tutorial also discusses the variability and complexity of these pathways, emphasizing the need to understand common elements rather than memorizing details.

What is the primary purpose of signal transduction pathways in the body?

• To transmit electrical signals between neurons

• To facilitate communication and coordination between cells

• To break down nutrients for energy

• To store genetic information

Which of the following is a common result of a conformational change in a receptor protein?

• Formation of new DNA strands

• Activation of another enzyme

• Immediate cell death

• Release of neurotransmitters

Why is it important to understand the common elements of signal transduction pathways?

• To develop new types of signal molecules

• To predict the exact response of every cell

• To identify patterns and themes for test questions

• To memorize every detail of each pathway

What is the role of beta-catenin in the Wnt signaling pathway?

• It breaks down glucose molecules

• It acts as a secondary messenger

• It transports oxygen in the blood

• It activates gene expression

How does the Wnt signaling pathway potentially contribute to insulin resistance?

• By increasing insulin production

• By modulating glucose uptake

• By enhancing insulin sensitivity

• By destroying insulin receptors

What initiates the RTK pathway?

• Opening of ion channels

• Activation of a G-protein

• Release of calcium ions

• Binding of a growth factor to the receptor

In the JAK-STAT pathway, what happens after the JAK proteins are phosphorylated?

• They form a dimer

• They release ATP

• They activate STAT proteins

• They bind to DNA directly

What is unique about the cortisol signaling pathway compared to others discussed?

• It is only active during embryogenesis

• Its receptors are located in the cytosol

• It requires a ligand to bind to a membrane receptor

• It involves a complex phosphorylation cascade

How does cortisol affect the liver during stress?

• It decreases glucose production

• It enhances protein synthesis

• It causes gluconeogenesis

• It increases fat storage

What is a potential negative effect of prolonged high cortisol levels?

• Increased muscle growth

• Improved memory

• Cell apoptosis

• Enhanced immune response