Question

1. by comparing model 1 and model 2, what structures are the same in both prokaryotic and eukaryotic cells?

1. what differences are there between a prokaryotic and eukaryotic cell?

1. refer to models 1 & 2 to complete the chart below. write yes or no in the box for each cell.

	bacterial cell	animal cell	plant cell	all cells
ribosome
cytoplasm
mitochondria
nucleolus
nucleus
dna
cell wall
prokaryotic
eukaryotic

Explanation:

Question 16

To determine the common structures in prokaryotic (e.g., bacterial) and eukaryotic (e.g., animal, plant) cells, we recall cell biology concepts. Prokaryotic cells lack a nucleus and membrane - bound organelles, but both prokaryotic and eukaryotic cells have a cell membrane (to control what enters/leaves the cell), ribosomes (for protein synthesis), cytoplasm (the fluid - like substance inside the cell where metabolic reactions occur), and DNA (the genetic material that carries the cell's genetic information).

1. Nucleus and membrane - bound organelles: Eukaryotic cells have a nucleus that encloses the genetic material (DNA) and other membrane - bound organelles like mitochondria, endoplasmic reticulum, Golgi apparatus, etc. Prokaryotic cells do not have a nucleus (their DNA is in a region called the nucleoid) and lack membrane - bound organelles.
2. Cell size: Generally, prokaryotic cells are much smaller (usually in the range of 1 - 5 μm in diameter) than eukaryotic cells (which can be 10 - 100 μm or more in diameter).
3. Cell wall composition: In prokaryotes (bacteria), the cell wall (if present) is mainly composed of peptidoglycan. In eukaryotes, plant cells have a cell wall made of cellulose, and fungal cells (a type of eukaryote) have a cell wall made of chitin. Animal cells (eukaryotic) do not have a cell wall.

for each row:

• Cell Membrane: All cells (prokaryotic and eukaryotic) have a cell membrane to regulate the passage of substances. So bacterial (prokaryotic), animal (eukaryotic), and plant (eukaryotic) cells all have it.
• Ribosome: Ribosomes are present in all cells as they are essential for protein synthesis. Prokaryotic cells have smaller ribosomes (70S), and eukaryotic cells have 80S ribosomes, but they are present in both.
• Cytoplasm: The fluid - filled region inside the cell (where many metabolic reactions occur) is present in all cell types.
• Mitochondria: Mitochondria are membrane - bound organelles (powerhouses of the cell) and are only present in eukaryotic cells. Bacterial cells (prokaryotic) do not have them.
• Nucleolus: The nucleolus is a structure within the nucleus of eukaryotic cells (involved in ribosome synthesis). Prokaryotic cells do not have a nucleus, so they do not have a nucleolus.
• Nucleus: The nucleus (a membrane - bound structure containing DNA) is a characteristic of eukaryotic cells. Prokaryotic cells have their DNA in a nucleoid region without a nuclear membrane.
• DNA: All cells (prokaryotic and eukaryotic) have DNA as their genetic material (though the organization differs: prokaryotic DNA is circular and not in a nucleus, eukaryotic DNA is linear and in the nucleus).
• Cell Wall: Bacterial cells (prokaryotic) have a cell wall (peptidoglycan - based), plant cells (eukaryotic) have a cell wall (cellulose - based), but animal cells (eukaryotic) do not have a cell wall.
• Prokaryotic: Bacterial cells are prokaryotic (they lack a nucleus and membrane - bound organelles), while animal and plant cells are eukaryotic.
• Eukaryotic: Animal and plant cells are eukaryotic (they have a nucleus and membrane - bound organelles), while bacterial cells are prokaryotic.

Answer:

The structures that are the same in both prokaryotic and eukaryotic cells are the cell membrane, ribosome, cytoplasm, and DNA.

Question 17