Question

electron micrographs represent extremely thin slices of cells. the micrograph in figure 5.4 contains a section of a nucleus and some cytoplasm. compare the organelles shown in this micrograph with organelles of the animal - cell model and identify the structures indicated by the arrows in figure 5.4. 1. ______ 2. ____ 3. ____ 4. ____ 5. ____ answer the following questions after observing the transmission electron micrograph in figure 5.4. 6. what cellular structures were visible in the transmission electron micrograph that were not apparent in the cells you observed using the compound light microscope? ____ 7. before they can be observed by using a transmission electron microscope, cells are sliced into very thin sections. what disadvantage does this procedure present in the study of cellular parts? ______ terms: chromatin, mitochondria, nuclear envelope, nucleolus, rough endoplasmic reticulum. figure 5.4 transmission electron micrograph of cellular components (23,000x). the view is only a portion of the cell. identify the numbered cellular structures, using the terms provided. ap r (keith r. porter, science source)

Explanation:

1. Based on typical cell - structure knowledge and the provided terms, we can identify the structures.

• Chromatin is often seen as a granular material in the nucleus.
• Mitochondria have a characteristic double - membrane structure and are involved in energy production.
• The nuclear envelope surrounds the nucleus.
• The nucleolus is a dense region within the nucleus.
• Rough endoplasmic reticulum has ribosomes attached to its surface.

1. Electron microscopes have higher resolution than compound light microscopes. Structures like ribosomes, endoplasmic reticulum, and mitochondria may not be visible with a light microscope but are visible with an electron microscope.
2. Slicing cells into thin sections for electron microscopy can disrupt the three - dimensional organization of the cell, making it difficult to understand the spatial relationships between different cellular components.

Answer:

1. Nucleolus
2. Chromatin
3. Nuclear envelope
4. Rough endoplasmic reticulum
5. Mitochondria
6. Ribosomes, endoplasmic reticulum, mitochondria (and other small or fine - structured organelles)
7. Disrupts the three - dimensional organization of the cell, making it hard to understand spatial relationships between components.