● Prokaryotes
○ single-celled (bacteria or archaea) with flagella (for movement)
○ Replicate through binary fission → split apart and make 2
... [Show More] exact copies of same cell
○ DNA is contained in single circular chromosome
● Eukaryotes
○ Plants, animals, fungi, bacteria
○ Reproduce through mitosis or meiosis
○ DNA is contained in multiple linear chromosomes
● All cells have cell membrane, cytoplasm, and DNA
● Plant cells contain all same organelles but contain cell walls with chloroplast
○ Organelles that aid in photosynthesis
ORGANELLES OF A CELL
Organelle Function
Cell membrane ● Controls movement of solutes in and out of the cell (proteins, enzymes, chemicals)
● Selectively permeable
● Made of double layer of phospholipids (hydrophilic phosphate head, hydrophobic fatty acid tail)
Nucleus ● contains DNA
● Codes for protein (transcription → process of making mRNA from gene)
● DNA replication and RNA transcription occur
Nucleolus ● Where most RNA and ribosomes are made
Mitochondria ● “Powerhouse of cell”
● Produce ATP via aerobic respiration
● Has a double membrane, small circular genome, and own ribosomes
Endoplasmic Reticulum ● where proteins are built and stored
● Smooth ER = no ribosomes
● Rough ER = ribosomes attached
Golgi Apparatus ● Sort, pack, and secrete proteins from ER
Lysosomes ● Contains enzymes that break cell structures
● Recycle old cell parts
Secretory Vesicles ● Transport and deliver molecules in and out of cell via cell membrane
●
Ribosomes ● Produce proteins as specified from DNA
Cilia/Flagella ● Cilia - Microscopic hair-like projections on some eukaryotic cells that aid in movement
● Flagella - whip-like tail used for movement; only on sperm cell in humans
Chromosomes ● Complex thread-like arrangements composed of DNA
● Found in cell nucleus
● Humans have 23 pairs (46 total)
Chromatin ● Cluster of genetic material made of DNA and proteins
● Forms chromosomes during cell division
Centrosome ● Organize microtubules of cell
● Centriole - substructure; assembles mitotic spindle in cell division
TRANSPORT MECHANISMS
● Passive Mechanisms
○ Does not require energy
○ From a high to low concentration
1) Simple Diffusion
a) Relies on concentration gradient to scatter molecules until equilibrium
2) Facilitated Diffusion
a) Uses carrier proteins to transport molecules across cell membrane
3) Osmosis [Show Less]