IB Biology Cell Structure Review

Capsule

A thick polysaccharide layer outside the cell wall. Used for extra protection, adhering cells together, and food reserves.

Cell Wall

Peptideology and polysaccharides that provide structural support and protection to the cell, maintaining its shape and is a protective outer layer.

Plasma Membrane

controls entry and exit of substances and plays a role in binary fission.

cytoplasm

Contains enzymes that catalyze the chemical reactions of metabolism and contains DNA

70’s Ribosomes

Ribosomes found in prokaryotic cells that are smaller than eukaryotic ribosomes and are involved in protein synthesis by translating mRNA

Plasmids

small circular DNA molecules found in prokaryotic cells that replicate independently of chromosomal DNA and often carry genes for antibiotic resistance.

Nucleoid

Region of the cytoplasm that contains circular naked DNA, which is the genetic instructions for the cell

Pili

Hair-like structures on the surface of prokaryotic cells that facilitate attachment to surfaces and other cells, playing a role in conjugation and adherence.

Flagella

Long, whip-like structures that enable prokaryotic cells to swim and move toward favorable environments.

Differences in a Prokaryotic cell

-Tiny

-No membrane bound organelles

-division by binary fusion

-cell wall with peptidegylcan

-DNA in nucioid (No nuclear membrane)

-Flagella rotates

-DNA is circular and naked

-Has 70’s Ribosomes

-Can have plamsids

Differences in Eukaryotic Cells

• bigger

• Membrane bound organelles

• fusion by binary fission (Mitosis or Meiosis)

• DNA is linear and associated with histones

• Has 80’s Ribosomes

• No plasmids

• DNA in a nucleus

• Flagella moves laterally

• Cell wall in plants made of cellulose

  • Unicellular or multicellular

Nucleus

Where DNA is replicated and transmitted.

Rough er

Plays a central role in the synthesis and transport of polysaccharides. It has bound ribosomes which synthesize the polypeptide inside of the (RER)

Smooth er

Plays a role in the synthesis of pospholipids and cholesterol for the formation and repair of membranes.

Golgi Apperarus

Modifies polypeptides into their functional state and sorts concentrated and pacts proteins into vesticles.

Mitochondrian

Are adapted for production of ATP by aerobic cellular resperation.

Chloroplast

Are adapted for photosynthesis which captures the vacole maintaines turger pre

Valcule

Stores and/or metabolic waste in plant cells. The valcole maintains turger pressure

Plasma Membrane

All cells have a lipid bi layer that functions as a barrier between aqueous solutions

Cell Wall

Helps develop turger pressure and proteins in the cell.

Lysome

A membrane bound organelle that contains digestive enzymes

80’s Ribosomes

larger and more complex, located in the cytoplasm of eukaryotic cells, and participates in the synthesis of a wide range of proteins

Cytosol

The fluid present in the cell and is a constituent of the cytoplasm

Nucleolus

A spherical structure found in the cells whose primary function is to produce and assemble the cell’s ribsomes.

lysosomes

contain digestive enzymes to degrade and recycle the cells old and damaged organelles or pathogens that have been engulfed by phagocytes.

Free Ribosomes

Synthesize polypeptides during translation. The polypeptides synthesized by free ribosomes will become proteins that function within a cell.

Chromosomes

Contains genes which are instructions for assembling proteins.