cells: building blocks of life

single celled organisms: most prokaryotes and
protists

multi-cellular organisms: plants, animals, and most fungi

microscope: an instrument used to see objects that are too small for the naked eye
Magnification: refers to an increase in the object’s image size compared to its actual size
Resolving power: is the ability of an optical instrument to show two points of a specimen as separate entities even if separated by the shortest distance

simple microscope: Uses one lens or a group of lenses in one unit to magnify objects

compound microscope: Uses two types of lens to magnify an object; ocular or eyepiece lens and objective lens

Light microscopes: can be used to explore the structures and functions of cells

electron microscope: uses a beam of electrons, which results in a 100-fold better resolution than the light microscope

Scanning electron microscopes: type of electron microscope; examine cell
surfaces
Transmission electron microscopes: type of electron microscope; useful for studying the internal structure of a cell

Cell theory: states that all living things are composed of cells and that all cells come from earlier cells

2 types of cells: prokaryotic and eukaryotic

Prokaryotic cells: Bacteria and Archaea
Eukaryotic cells: protists, plants, fungi, and animals

basic features of all cells: Plasma membrane, cytosol, chromosomes, and ribosomes

cytosol: a thick, jelly-like fluid that cellular components are suspended in

ribosomes: tiny structures that build proteins according to the instructions from MRNA; are either in the cytoplasm, attached to the ER(endoplasmic reticulum), or attached to the outside of the nucleus

age of prokaryotic cells vs eukaryotic cells: prokaryotic cells are older than eukaryotic cells

size and complexity of prokaryotic vs eukaryotic: Prokaryotic are smaller and simpler, eukaryotic are larger and more complex

traits of prokaryotic cells: no nucleus, no organelles, cell wall, can have a flagella or

nucleoid: nucleus like region in prokaryotic cells; holds DNA

flagella: long tail that helps prokaryotic cells move liquid environment

pili: multiple short hair like tails that help prokaryotic cells move and attach themselves to things

traits of eukaryotic cells: have organelles, nucleus

organelles: membrane-enclosed structures that perform specific functions

cytoplasm: region between the nucleus and plasma membrane; consists of various organelles suspended in cytosol

chloroplasts: where photosynthesis occurs (plant cells only)

lysosomes: has digestive enzymes surrounded by membranes (animal cells only)

central vacuole: store organic nutrients, absorb water, and contain pigments that attract pollinating insects or poisons that protect against plant-eating animals

plasma membrane: separates the interior of all cells from the outside environment to protect the cells

content of the plasma membrane: phospholipids

2 regions of a phospholipid: hydrophilic “head” of a negatively charged phosphate group, and 2 hydrophobic non polar fatty acid “tails”

endomembrane system: the the nuclear envelope, the endoplasmic reticulum, the Golgi apparatus, lysosomes, and vacuoles

nucleus: control center of the cell, contains genes, and has a nucleolus, creates the components of ribosomes

gene: a stretch of DNA that stores the information necessary to produce a particular protein

The nuclear envelope: encloses the nucleus separating it from the cytoplasm; has pores to allow certain things through

nucleolus: inside then nucleus; where ribosomes are made

chromosome: one long chromatin fiber

number of chromosomes in the human body: 46

endoplasmic reticulum (ER): produces an enormous variety of molecules, is connected to the nuclear envelope, and is composed of smooth and rough ER

Rough ER: production, folding, quality control and despatch of some proteins; “rough” due to ribosomes being attached to it

transport vesicles: sacs made of the membrane that bud off from the rough ER and transport product from the rough ER to other locations in the cell

smooth er: produces lipids, including steroids, and helps liver cells detoxify circulating drugs

Golgi apparatus: works in partnership with the ER and receives, refines, stores, and distributes chemical products of the cell

lysosomes: a membrane-bound sac of digestive enzymes found in animal cells; can digest old/damaged organelles and destroy harmful bacteria

3 main functions of lysosomes: digest food, cleans up waste, and recycle old cell parts

vacuoles: large sacs made of a membrane that buds off from the ER or Golgi apparatus

function of vacuoles in animal cells: Store food, waste, and other materials

Photosynthesis: The process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water; occurs in the chloroplasts

chloroplast: where photosynthesis happen; has 3 layers: outer membrane, inner membrane, inter membrane space

Stroma: a thick fluid within the chloroplast
Grana: stacks of thylakoids
thylakoids: membrane-enclosed discs that trap light energy and convert it to chemical energy

mitochondria: produces ATP energy

Cristae: inner membrane compartmentalized into numerous cristae (mitochondria)
Matrix: Fluid-filled and contain enzymes for cell respiration (mitochondria)