Question

part 4: application / critical thinking

1. a person eats a meal of pasta, chicken, and avocado. identify the main biomolecule type in each food and explain its function in the body.
2. why might a muscle cell contain more mitochondria than a skin cell?
3. a scientist discovers a new organism that does not have a nucleus or membrane - bound organelles. is it prokaryotic or eukaryotic? explain.
4. a cell is observed under the microscope and is found to have a cell wall, chloroplasts, and a large central vacuole. what type of cell is this, and how do these structures help the organism survive?
5. if the ribosomes in a cell stopped working, what would happen to the cell and why?

Explanation:

Step1: Identify biomolecules in pasta

Pasta is mainly composed of carbohydrates. Carbohydrates are the body's primary energy - source, broken down into glucose for energy.

Step2: Identify biomolecules in chicken

Chicken is rich in proteins. Proteins are essential for growth, repair, and maintenance of body tissues, and also function as enzymes, hormones, etc.

Step3: Identify biomolecules in avocado

Avocado contains a significant amount of lipids (fats). Lipids store energy, insulate the body, and are part of cell membranes.

Step4: Answer muscle - cell mitochondria question

Muscle cells require more energy for movement and contraction. Mitochondria are the power - houses of the cell, producing ATP (energy). So, muscle cells have more mitochondria to meet their high - energy demands compared to skin cells which have lower energy requirements.

Step5: Classify the new organism

Organisms without a nucleus or membrane - bound organelles are prokaryotes. This is the defining characteristic of prokaryotic cells, distinguishing them from eukaryotic cells which have a nucleus and membrane - bound organelles.

Step6: Identify the cell type

A cell with a cell wall, chloroplasts, and a large central vacuole is a plant cell. The cell wall provides structural support and protection. Chloroplasts carry out photosynthesis, converting light energy into chemical energy. The large central vacuole stores water, nutrients, and waste products, and also helps maintain cell turgor pressure.

Step7: Analyze ribosome malfunction

Ribosomes are responsible for protein synthesis. If they stop working, the cell cannot produce proteins. Proteins are crucial for many cellular functions such as enzyme - catalyzed reactions, structural support, and transport. So, the cell would eventually die due to the lack of essential proteins.

Answer:

1. Pasta: Carbohydrates, primary energy - source. Chicken: Proteins, for growth and repair. Avocado: Lipids, for energy storage and insulation.
2. Muscle cells need more energy for movement, so they have more mitochondria.
3. Prokaryotic. Prokaryotes lack a nucleus and membrane - bound organelles.
4. Plant cell. Cell wall for support, chloroplasts for photosynthesis, large central vacuole for storage and turgor.
5. The cell would die as ribosomes are needed for protein synthesis and proteins are essential for cell functions.