Cells Crossword

1234567891011121314151617181920
Across
  1. 2. vacuole In a mature plant cell, a large membranous sac with diverse roles in growth, storage, and sequestration of toxic substances.
  2. 3. apparatis An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulum and synthesize some products, notably noncellulose carbohydrates.
  3. 5. reticulum An extensive membranous network in eukaryotic cells, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions.
  4. 6. The contents of the cell bounded by the plasma membrane; in eukaryotes, the portion exclusive of the nucleus.
  5. 8. A globular protein that links into chains, two of which twist helically about each other, forming microfilaments (actin filaments) in muscle and other kinds of cells.
  6. 10. system The collection of membranes inside and surrounding a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles; includes the plasma membrane, the nuclear envelope, the smooth and rough endoplasmic reticulum, the Golgi apparatus, lysosomes, vesicles, and vacuoles.
  7. 13. A network of microtubules, microfilaments, and intermediate filaments that extend throughout the cytoplasm and serve a variety of mechanical, transport, and signaling functions.
  8. 15. A membrane-enclosed sac of hydrolytic enzymes found in the cytoplasm of animal cells and some protists.
  9. 16. A non-membrane-enclosed region in a prokaryotic cell where its chromosome is located.
  10. 18. cell A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with prokaryotic cells (bacteria and archaea) are called prokaryotes.
  11. 19. junction A type of intercellular junction in animal cells, consisting of proteins surrounding a pore that allows the passage of materials between cells.
  12. 20. A structure in the centrosome of an animal cell composed of a cylinder of microtubule triplets arranged in a “9 + 0” pattern. A centrosome has a pair of centrioles.
Down
  1. 1. A specialized structure in the nucleus, consisting of chromosomal regions containing ribosomal RNA (rRNA) genes along with ribosomal proteins imported from the cytoplasm; site of rRNA synthesis and ribosomal subunit assembly. See also ribosome.
  2. 4. An organelle in eukaryotic cells that serves as the site of cellular respiration; uses oxygen to break down organic molecules and synthesize ATP.
  3. 7. An organelle containing enzymes that transfer hydrogen atoms from various substrates to oxygen (O2), producing and then degrading hydrogen peroxide (H2O2).
  4. 9. theory The theory that mitochondria and plastids, including chloroplasts, originated as prokaryotic cells engulfed by a host cell. The engulfed cell and its host cell then evolved into a single organism. See also endosymbiosis.
  5. 11. cell A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with eukaryotic cells (protists, plants, fungi, and animals) are called eukaryotes.
  6. 12. membrane The membrane at the boundary of every cell that acts as a selective barrier, regulating the cell's chemical composition.
  7. 14. A structure present in the cytoplasm of animal cells that functions as a microtubule-organizing center and is important during cell division. A centrosome has two centrioles.
  8. 17. A long cellular appendage specialized for locomotion. Like motile cilia, eukaryotic flagella have a core with nine outer doublet microtubules and two inner single microtubules (the “9 + 2” arrangement) ensheathed in an extension of the plasma membrane. Prokaryotic flagella have a different structure.