Q1. Match the type of cell signaling:

Background

Topic: Cell Communication

This question tests your understanding of different types of cell signaling, including how cells communicate over short and long distances.

Key Terms:

• Endocrine signaling: Long-distance signaling via hormones in the bloodstream.

• Synaptic signaling: Short-distance signaling between neurons using neurotransmitters.

Step-by-Step Guidance

1. Read each description and identify whether it refers to signaling across long distances or between neighboring cells.

2. Recall that hormones typically travel through the bloodstream for long-distance communication (endocrine signaling).

3. Remember that neurons communicate with each other via synaptic signaling, which involves neurotransmitters crossing a synapse.

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Q2. What are the three steps of cell signaling? What happens during each step?

Background

Topic: Cell Signaling Pathways

This question tests your knowledge of the basic steps in cell signaling: reception, transduction, and response.

Key Terms:

• Reception: The cell detects a signaling molecule from the outside.

• Transduction: The signal is relayed and amplified inside the cell.

• Response: The cell reacts to the signal, often by changing its activity.

Step-by-Step Guidance

1. Identify the first step, where the cell receives the signal (reception).

2. Describe the second step, where the signal is passed through a series of molecules (transduction).

3. Explain the third step, where the cell makes a change in response to the signal (response).

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Q3. What are the three major types of membrane receptors?

Background

Topic: Membrane Receptors

This question tests your knowledge of the main classes of membrane receptors involved in cell signaling.

Key Terms:

• G-protein coupled receptors (GPCRs)

• Receptor tyrosine kinases (RTKs)

• Ion channel receptors

Step-by-Step Guidance

1. Recall the three main types of membrane receptors.

2. Think about their functions: GPCRs activate G proteins, RTKs phosphorylate tyrosines, and ion channels allow ions to pass.

3. Write the names in the blanks provided.

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Q4. Properly order the steps of signaling via a G-protein coupled receptor

Background

Topic: GPCR Signaling Pathway

This question tests your understanding of the sequence of events in G-protein coupled receptor signaling.

Key Terms:

• Ligand: A molecule that binds to a receptor.

• GDP/GTP: Guanine nucleotides involved in G protein activation.

• Enzyme: Triggers cellular response.

Step-by-Step Guidance

1. Identify the step where the ligand binds to the GPCR, activating the G protein.

2. Next, the activated G protein dissociates from the receptor and activates an enzyme.

3. The enzyme triggers a cascade that leads to a cellular response.

4. Finally, the G protein hydrolyzes GTP to GDP, becoming inactive.

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Q5. What is a second messenger? What is its purpose?

Background

Topic: Second Messengers in Cell Signaling

This question tests your understanding of the role of second messengers in amplifying and relaying signals inside the cell.

Key Terms:

• Second messenger: Small molecules that transmit signals from receptors to target molecules inside the cell.

• Amplification: Increasing the strength of the signal.

Step-by-Step Guidance

1. Define what a second messenger is.

2. Explain its purpose: to relay and amplify the signal inside the cell.

3. Think of examples like cAMP, Ca2+, and IP3.

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Q6. Give three examples of second messengers.

Background

Topic: Second Messengers

This question tests your ability to recall common second messengers used in cell signaling pathways.

Key Terms:

• cAMP (cyclic AMP)

• Ca2+ (calcium ions)

• IP3 (inositol triphosphate)

Step-by-Step Guidance

1. Recall the most common second messengers.

2. Write down three examples.

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Q7. A group of enzymes called __________ add a phosphate group to a protein, while another group of enzymes called __________ remove a phosphate group from a protein.

Background

Topic: Protein Modification in Signaling

This question tests your knowledge of enzymes involved in phosphorylation and dephosphorylation.

Key Terms:

• Kinases: Add phosphate groups.

• Phosphatases: Remove phosphate groups.

Step-by-Step Guidance

1. Recall the names of enzymes that add and remove phosphate groups.

2. Fill in the blanks with the correct terms.

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Q8. True or false: adding a phosphate group ALWAYS results in activation of a protein, while removing a phosphate group always results in deactivation of the protein.

Background

Topic: Regulation of Protein Activity

This question tests your understanding of how phosphorylation affects protein activity.

Key Terms:

• Phosphorylation: Addition of a phosphate group.

• Dephosphorylation: Removal of a phosphate group.

Step-by-Step Guidance

1. Consider whether phosphorylation always activates proteins.

2. Think about whether dephosphorylation always deactivates proteins.

3. Recall that the effect depends on the specific protein and context.

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Q9. The second messenger cAMP is made by the enzyme __________ hydrolyzing pyrophosphate from the molecule __________.

Background

Topic: cAMP Production

This question tests your knowledge of how cAMP is synthesized in cells.

Key Terms:

• Adenylyl cyclase: Enzyme that makes cAMP.

• ATP: Molecule used to make cAMP.

Step-by-Step Guidance

1. Recall the enzyme responsible for cAMP production.

2. Identify the molecule that is converted into cAMP.

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Q10. What area of the cell has a low Ca2+ concentration?

Background

Topic: Calcium Signaling

This question tests your knowledge of calcium ion distribution in cells.

Key Terms:

• Cytosol: Fluid inside the cell.

• Ca2+ concentration: Important for signaling.

Step-by-Step Guidance

1. Recall where Ca2+ is kept at low levels in the cell.

2. Think about the cytosol versus organelles like the ER.

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Q11. The enzyme __________ cleaves a specific membrane lipid to generate DAG and PIP2 (which is converted to IP3).

Background

Topic: Lipid Signaling Pathways

This question tests your knowledge of enzymes involved in generating second messengers from membrane lipids.

Key Terms:

• Phospholipase C: Enzyme that cleaves membrane lipids.

• DAG and IP3: Second messengers.

Step-by-Step Guidance

1. Recall the enzyme responsible for cleaving PIP2.

2. Identify the products: DAG and IP3.

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Q12. What are the four key aspects of cell signaling?

Background

Topic: Cell Signaling Regulation

This question tests your knowledge of the main features that regulate cell signaling pathways.

Key Terms:

• Amplification

• Specificity

• Scaffolding

• Termination

Step-by-Step Guidance

1. Recall the four aspects: amplification, specificity, scaffolding, and termination.

2. Match each aspect to its description.

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Q13. Controlled cell death is called __________.

Background

Topic: Apoptosis

This question tests your knowledge of the term for programmed cell death.

Key Terms:

• Apoptosis: Controlled cell death.

Step-by-Step Guidance

1. Recall the term for controlled cell death.

2. Write the term in the blank.

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Q14. Briefly explain the molecular mechanism of apoptosis in C. elegans.

Background

Topic: Apoptosis Mechanisms

This question tests your understanding of how apoptosis is regulated in the model organism C. elegans.

Key Terms:

• Caspases: Proteins involved in apoptosis.

• CED-3, CED-4, CED-9: Key genes in C. elegans apoptosis.

Step-by-Step Guidance

1. Recall the main proteins involved in apoptosis in C. elegans.

2. Describe how CED-9 inhibits apoptosis, while CED-4 and CED-3 promote it.

3. Explain the cascade that leads to cell death.

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Q15. What is a gamete? How many sets of chromosomes does a gamete have? How many sets of chromosomes does a somatic cell have?

Background

Topic: Chromosome Number in Cells

This question tests your understanding of the difference between gametes and somatic cells in terms of chromosome sets.

Key Terms:

• Gamete: Sex cell (egg or sperm).

• Somatic cell: Any body cell except gametes.

• Haploid: One set of chromosomes.

• Diploid: Two sets of chromosomes.

Step-by-Step Guidance

1. Define what a gamete is.

2. Recall that gametes are haploid (one set of chromosomes).

3. Somatic cells are diploid (two sets of chromosomes).

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Q16. The __________ is the narrow waist of a duplicated chromosome; the region where two sister chromatids are most tightly attached.

Background

Topic: Chromosome Structure

This question tests your knowledge of chromosome anatomy.

Key Terms:

• Centromere: Region where chromatids are attached.

Step-by-Step Guidance

1. Recall the term for the region where sister chromatids are joined.

2. Write the term in the blank.

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Q17. Label how many chromosomes and chromatids the cell would have at each phase of the cell cycle.

Background

Topic: Cell Cycle and Chromosome Number

This question tests your understanding of how chromosome and chromatid numbers change during the cell cycle.

Key Terms:

• Chromosome: DNA molecule with genetic material.

• Chromatid: One copy of a duplicated chromosome.

• Cell cycle phases: G1, S, G2, M.

Step-by-Step Guidance

1. Review the cell cycle diagram and identify the phases: G1, S, G2, M.

2. Recall that in G1, the cell has unreplicated chromosomes (one chromatid per chromosome).

3. During S phase, DNA is replicated, so each chromosome now consists of two sister chromatids.

4. In G2 and M, the cell has duplicated chromosomes (two chromatids per chromosome).

5. After mitosis, each daughter cell returns to having single chromatids per chromosome.

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Q18. Correctly name and order the steps of mitosis:

Background

Topic: Mitosis Stages

This question tests your knowledge of the sequence and description of mitosis stages.

Key Terms:

• Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Step-by-Step Guidance

1. Recall the order of mitosis stages: prophase, metaphase, anaphase, telophase, cytokinesis.

2. Match each stage to its description (e.g., chromosomes align, chromatids separate).

3. Write the names in the correct order.

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Q19. Label the stages of mitosis in the figure below:

Background

Topic: Mitosis Stages (Visual)

This question tests your ability to visually identify and label the stages of mitosis.

Key Terms:

• Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Step-by-Step Guidance

1. Examine the diagram and identify the features of each stage (e.g., chromosome alignment, chromatid separation).

2. Recall the order and characteristics of mitosis stages.

3. Label each stage based on the visual cues.

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