Question

which cell structures are seen in all cell types? check all that apply. dna cytoplasm nucleus ribosomes cell membrane

Explanation:

• DNA: All cells (prokaryotic and eukaryotic) contain genetic material, which is DNA (or RNA in some viruses, but cells have DNA). Prokaryotes have circular DNA, eukaryotes have linear DNA in the nucleus (and mitochondrial/chloroplast DNA).
• Cytoplasm: The gel - like substance within the cell where many metabolic reactions occur. Both prokaryotic and eukaryotic cells have cytoplasm.
• Ribosomes: Responsible for protein synthesis. Prokaryotic cells have 70S ribosomes, eukaryotic cells have 80S ribosomes (and 70S in organelles like mitochondria and chloroplasts), so all cells have ribosomes.
• Cell membrane: A phospholipid bilayer that encloses the cell, regulating the entry and exit of substances. Both prokaryotic (like bacteria) and eukaryotic cells have a cell membrane.
• Nucleus: Only eukaryotic cells have a true nucleus (a membrane - bound organelle containing DNA). Prokaryotic cells do not have a nucleus; their DNA is in the nucleoid region. So the nucleus is not present in all cell types.

Answer:

DNA, cytoplasm, ribosomes, cell membrane