organelles

cell/plasma membrane

* regulates what enters & leaves the cell
* selectively permiable

cytoplasm

* a jelly-like substance enclosed by a cell membrane
* provides a medium for chemical reactions to take place

cytosol

liquid portion of cytoplasm

where are organelles found?

in the cytoplasm

nucleus

* controls the normal activities of the cell
* largest organelle

DNA

* makes up chromosomes inside the nucleus
* hereditary material of the cell

nuclear envelope

* a double membrane surrounding the nucleus
* contains nuclear pores
* connected to the ER

nuclear pores

* regulates what enters & leaves nucleus
* RNA & ribosomes can leave

chromosomes

* contain genes that control the characteristics of the cell
* in dividing cells, formed by condensed DNA wrapped around proteins

chromatin

when DNA is spread out & appears as a mass (in non-diving cells)

nucleolus

* inside the nucleus
* cells may contain 1-3
* disappear during cell division & reappear later
* makes ribosomes that make proteins

ribosomes

* make proteins for the cell
* made of proteins and RNA

cytoskeleton

* made of proteins

__Functions:__
* helps maintain cell shape
* helps move organelles around

microfilaments

threadlike proteins in the cytoskeleton

microtubules

tubelike proteins in the cytoskeleton

actin

the protein in microfilaments

tubulin

the protein in microtubules

centrioles

* only in animal cells
* come in pairs
* found near the nucleus
* made of a bundle of microtubules
* during cell division, they help to pull chromosomes apart.

mitochondria

* powerhouse of the cell
* generates cellular energy/ATP
* more active cells have more mitochondria (ex. muscles)
* found in all eukaryotic cells
* surrounded by double membrane
* has its own DNA

where does cellular respiration take place?

mitochondria

cristae

* inner membrane of mitochondria
* folded to increase surface area for more chemical reactions

matrix

interior compartment of the mitochondria

endoplasmic reticulum (ER)

* network of hollow membrane tubes
* connected to nuclear envelope & cell membrane
* functions in synthesis & transport of cell products

rough ER

proteins are made in ribosomes on its surface and threaded into interior of the ER to be modified & transported (export)

smooth ER

* no ribosomes
* attached to ends of rough ER
* makes cell products for use inside the cell

3 functions of smooth ER

1. makes membrane lipids
2. regulates calcium
3. destroys toxic substances (liver)

what makes up the endomembrane transport system

nuclear membrane connected to ER connected to cell membrane

protein synthesis

when ribosomes join amino acids to make proteins

free ribosomes

found in the cytoplasm & used inside the cell

golgi bodies

* look like stacks of pancakes/flattened sacs
* Trans face: shipping (export)
* Cis face: receiving (ER to Golgi)
* proteins modified by this come from RER

transport vesicles

transport proteins from ER to Golgi & from Golgi to cell membrane

lysosomes

* contain digestive enzymes
* break down food, bacteria, & worn out cell parts
* function: cell digestion

apoptosis

programmed cell death

autolysis

when the cell is destroyed after an injury or death

phagocytosis

the process of which lysosomes take in food

functions cilia & flagella

1. Moving cells
2. moving fluids across the cell’s surface
3. moving particles across the cell’s surface

microtubule arrangement of cilia & flagella

9+2

cilia

* shorter & more numerous
* Ex- Respiratory system: Moves dust particles away from lungs

flagella

* longer & fewer (usually 1-3)
* only cell in advanced animal w/ this is **sperm**

vacuoles

* fluid-filled sacs for storage
* present in plant cells

cell sap

* stored in central vacuoles
* contains substances like water, toxins harmful to the plant, salts, wastes, and enzymes

contractile vacuoles

* found in unicellular protists like paramecia
* regulates water by pumping out excess (homeostasis)
* keeps cell from bursting

cell wall

* nonliving layer found in plants , fungi, & bacteria
* support & protect the cell
* outside the cell membrane

plant cell walls

cellulose

bacterial cell walls

peptidoglycan

fungal cell walls

chitin

chlorophyll

* pigment found inside chloroplasts
* captures the energy from the sun & uses it to make food
* embedded inside thylakoid membrane

chloroplasts

* found in producers that are photoautotrophs (eukaryotes)
* surrounded by a double membrane
* contain their own DNA (so they can reproduce themselves), pigments, & enzymes

chloroplast’s outer membrane

smooth

chloroplast’s inner membrane

modified into sacs (thylakoids)

grana

stacks of thylakoids that are interconnected

stroma

gel like material surrounding thylakoids

which cells never have chloroplasts?

animal / bacteria / fungi

photsynthesis

the food making process that takes place inside of chloroplasts

peroxisomes

digest fatty acids & alcohol

catalase

oxidative enzyme

plastids

* found in plants & algae
* do photosynthesis
* 3 types: chloroplasts, leucoplasts, chromoplasts

leucoplasts

plastids where you store starch

chromoplasts

plastids that store brightly-colored pigment (make carrots orange, attract insects to flowers)