Question 1: Define the term 'organelle' as it pertains to animal cells.

Answer: An organelle is a specialized structure within a cell that performs a specific function.

Question 2: Explain the primary function of the nucleus in an animal cell.

Answer: The nucleus acts as the control center of the cell, regulating gene expression and storing genetic information.

Question 3: Multiple Choice: Which organelle is responsible for energy production in animal cells?

Answer: Mitochondria

Question 1: Calculate the surface area to volume ratio (SA:V) of a spherical animal cell with a diameter of 20 micrometers. Use the formulas: Surface Area = 4πr^2, Volume = (4/3)πr^3.

Answer: SA:V ratio = (Surface Area) / (Volume) = (4πr^2) / ((4/3)πr^3) = 3 / r. For r = 10 μm, ratio = 3 / 10 = 0.3 μm^-1.

Question 2: If the concentration of a protein in the cytoplasm is 50 micrograms per milliliter, how much protein is present in a cell volume of 5,000 cubic micrometers? (Note: 1 milliliter = 1,000,000 cubic micrometers.)

Answer: Total protein = concentration × volume = 50 μg/mL × (5,000 μm^3 / 1,000,000 μm^3/mL) = 50 μg/mL × 0.005 mL = 0.25 μg.

Question 1: Describe a simple experiment to observe animal cell membranes using a microscope. Include variables to control and safety precautions.

Answer: Students can prepare a wet mount of cheek cell samples by gently scraping the inside of their cheek, placing the sample on a slide with a drop of water, and covering it with a cover slip. Variables to control include sample amount and microscope magnification. Safety precautions involve handling the sample hygienically, washing hands afterward, and using the microscope carefully to avoid damage.

Question 1: A study reports that in a certain animal tissue, the average number of mitochondria per cell is 300, and the average cell volume is 2,000 cubic micrometers. Calculate the mitochondria density per cubic micrometer of cell volume.

Answer: Mitochondria density = Number of mitochondria / Cell volume = 300 / 2000 = 0.15 mitochondria per μm^3.

Question 2: Based on the data, discuss how mitochondrial density might relate to the energy demands of the cell.

Answer: Higher mitochondrial density indicates greater energy production capacity, which is essential for cells with high energy demands such as muscle or nerve cells.

Question 1: Explain how understanding mitochondrial function can contribute to developing treatments for metabolic diseases.

Answer: Knowing how mitochondria produce energy helps in developing therapies that target mitochondrial dysfunction, which is linked to metabolic diseases like diabetes and mitochondrial myopathies.

Question 2: Discuss how advances in cell biology have improved the efficiency of biopharmaceutical production using animal cell cultures.

Answer: Advances such as genetic engineering and optimized culture media have increased yield and quality of therapeutic proteins produced in animal cell cultures, improving drug development and production efficiency.