Putting It Together: Cellular Structure

In this module, we’ve learned about several different cell components. Table 1 provides a summary of all the components we covered, as well as their functions and locations. Attempt the following interactive questions at least once without referencing the table!

Table 1. Components of Prokaryotic and Eukaryotic Cells
Cell Component Function Present in Prokaryotes? Present in Animal Cells? Present in Plant Cells?
Cytoplasm Provides turgor pressure to plant cells as fluid inside the central vacuole; site of many metabolic reactions; medium in which organelles are found Yes Yes Yes
Nucleus Cell organelle that houses DNA and directs synthesis of ribosomes and proteins No Yes Yes
Nucleolus Darkened area within the nucleus where ribosomal subunits are synthesized. No Yes Yes
Ribosomes Protein synthesis Yes Yes Yes
Mitochondria ATP production/cellular respiration No Yes Yes
Peroxisomes Oxidizes and thus breaks down fatty acids and amino acids, and detoxifies poisons No Yes Yes
Endoplasmic reticulum Modifies proteins and synthesizes lipids No Yes Yes
Golgi apparatus Modifies, sorts, tags, packages, and distributes lipids and proteins No Yes Yes
Vesicles and vacuoles Storage and transport; digestive function in plant cells No Yes Yes
Centrosome Unspecified role in cell division in animal cells; source of microtubules in animal cells No Yes No
Lysosomes Digestion of macromolecules; recycling of worn-out organelles No Yes No
Chloroplasts Photosynthesis No No Yes
Cytoskeleton Maintains cell’s shape, secures organelles in specific positions, allows cytoplasm and vesicles to move within cell, and enables unicellular organisms to move independently Yes Yes Yes
Flagella Cellular locomotion Some Some No, except for some plant sperm cells.
Cilia Cellular locomotion, movement of particles along extracellular surface of plasma membrane, and filtration Some Some No
Plasma membrane Separates cell from external environment; controls passage of organic molecules, ions, water, oxygen, and wastes into and out of cell Yes Yes Yes
Cell wall Protection, structural support and maintenance of cell shape Yes, primarily peptidoglycan No Yes, primarily cellulose

INHERITED DISEASES

Let’s look back to our earlier disease list:

  • Pompe Disease: characterized by excess accumulation of glycogen in muscle cells
  • Leigh Disease: progressive disorder of lesions (dead or dying cells) in the brain
  • Emery-Dreifuss muscular dystrophy: wasting and weakness in muscles of the shoulders, upper arms, and calf muscles

The following organelles are what cause the each disorder. As you explore the different websites that highlight each disease, think about how the function of these organelles directly relates to the disease symptoms.

Flashcards

It is tempting to view different topics as completely separate, but in fact the ideas we cover in this course are often connected to one another. If you don’t retain the vocabulary from module to module, those connections can be missed. As you continue on, remember to come back and review the terms you’ve learned in order to increase your depth of knowledge.