Prokaryotic and Eukaryotic Cells, Endosymbiotic Theory, Extracellular Matrix, and Cellular Respiration

Flashcards covering prokaryotic and eukaryotic cell evolution, endosymbiotic theory, extracellular matrix, ATP structure and function, and the basics of cellular respiration and fermentation.

How is the endomembrane system believed to have formed in early eukaryotic cells?

The outer cell membrane unfolded and got caught inside the cytoplasm of some cells, forming the different membrane components.

What structures are believed to have formed if these internal membranes wrapped around the DNA?

The nucleus, endoplasmic reticulum, and Golgi apparatus.

What does the endosymbiotic theory explain?

The origin of mitochondria and chloroplasts in eukaryotic cells.

According to the endosymbiotic theory, how did mitochondria originate?

Smaller prokaryotic cells that could use oxygen to make energy were engulfed by a larger early eukaryotic cell and lived symbiotically within it.

How did chloroplasts originate, according to the endosymbiotic theory?

An early eukaryotic cell that already contained mitochondria engulfed a small prokaryotic cell with photosynthetic membranes, which then lived symbiotically within it.

What evidence supports the endosymbiotic theory for mitochondria and chloroplasts?

They have two membranes, their own circular DNA, make their own energy, and reproduce by binary fission on a timeline separate from the eukaryotic cell.

What is the extracellular matrix?

A large amount of biological molecules (proteins, lipids, carbohydrates) hanging off the outside of a cell that serves many purposes.

What are some purposes of the extracellular matrix?

Cell-cell communication, self-identity, recognition by the immune system, and differentiation by cell type (e.g., heart cells vs. liver cells).

Why is the extracellular matrix important in organ donation?

Matching the 'self-identity' molecules in the extracellular matrix helps prevent the immune system from rejecting the donated organ.

What are MHC proteins (Major Histocompatibility Proteins)?

Proteins on the surface of immune cells (T and B cells) that allow them to identify different cell types in our body and whether those cells are a part of us or not.

What is ATP and what is its primary function?

ATP (adenosine triphosphate) is a molecule used for energy storage and retrieval inside cells, providing potential energy for cellular processes.

What is the structure of ATP most closely related to?

A nucleotide with three phosphate groups attached (composed of a nitrogenous base adenine, a ribose sugar, and three phosphate groups).

Do all cell types require ATP to function normally and survive?

Yes, animal cells, plant cells, and bacterial cells (prokaryotes) all require ATP.

Where does an animal's biomass (dry weight) primarily come from as it grows?

The food that the animal eats.

What are the two possible ways cells use broken-down food molecules?

To create new raw materials for the cell (biosynthesis) or to make cellular fuel (ATP) through processes like cellular respiration.

What are the two major ways eukaryotic cells process food for energy?

Aerobically through cellular respiration (uses oxygen) or anaerobically through fermentation (without oxygen).

What is the overall equation for cellular respiration?

Food + Oxygen -> ATP + Carbon Dioxide + Water.

What are the four major stages of cellular respiration?

The lecture mentions four major stages but does not specify their names in this segment.