Bio: Cell Organelles and Cell Transport

What is the largest human cell?

The egg cell. It's the size of a period in a book.

What is cell sized based off of?

Ratio of surface area (cm^2) to volume (cm^3). Cells want to increase surface area to help with absorbtion but keep volume low.

What is the difference between Prokaryotes and Eukaryotes?

Eukaryotes have endomembranous organelles and DNA within a nucleus while the DNA in a prokaryote is free-floating

What are main Eukaryote Organelles?

The 'organs' of the cell- they each have a specific function within the cell

What are the organelles?

Nucleus, Smooth and Rough ER, Golgi Apparatus, Cell Membrane, Lysosomes, Mitochondrion, Ribosomes, Chloroplasts

Nucleus

Has a nuclear envelope (double membrane). Contains the genes/DNA of the cell.

Double Membrane

4 single layers of phospholipids- 2 hydrophilic and 2 hydrophobic

Single membrane

2 layers of phospholipids- 1 hydrophilic and 1 hydrophobic

Endoplasmic Reticulum (ER)

Producer of needed molecules. Has 2 subcatagories: Rough and Smooth ER. Rough ER has ribosomes on its surface that makes proteins. Smooth ER lacks ribosomes and instead makes lipids, amino acids and creates vesicles for transport.

Vesicles

Bubbles for transport of the products the ER makes to travel the cell. Made of bubbles pinched off from the membrane.

Golgi Apparatus

Packages chemicals into vesicles for transport

Lysosomes

Kamikaze of the cell. Vesicular organelles that contain 'nasty' enzymes. Lysosomes are released when pathogens invade the cell. They self destruct the cell but also kill the pathogens.

Vacuole

Hole/Bubble used for storage

Mitochondrion

Creates the ATP cells use for energy. It is double membraned and full of ribosomes. Also contains DNA in the form of plasmids and its genes are only used for mitochondria activites.

Endosymbiont Hypothesis

Theory that mitochondria and chloroplasts evolved from bacteria that entered and lived in a host cell.

Chloroplast

Double membraned. Has its own supply of DNA used for chloroplast stuff. Contains ribosomes. Its primary function is to make glucose for autotrophs. Not in humans

Autotroph

Organism that makes its own glucose ie: plants

Ribosomes

Makes proteins

Cytoskeletons

A network of long, straight proteins that provide structure for the cell

Cytoplasm/Cytosol

A jellylike fluid inside the cell in which the organelles are suspended

Cell wall

A rigid layer of nonliving material that surrounds the cells of plants and some other organisms.

Extracellular Matrix

The substance in which animal tissue cells are embedded, consisting of protein and polysaccharides.

Microtubules

A hollow rod composed of tubulin proteins that makes up part of the cytoskeleton in all eukaryotic cells and is found in cilia and flagella.

Cell for Plasmal membrane

2 parts: Fluid and Mosaic. The membrane is in fluid motion and the mosaic portion has the organelles inside it

Permeability

Allows passage of certain particles in and out of the cell- passive transport

Passive transport

No energy needed in transport. Movement through interstitial molecule spaces

Active Transport

Energy (ATP) is required for transport. Moves stuff against the law of diffusion- moving from areas of low concentration to high concentration. Uses pump proteins

impermeable

Nothing is allowed in or out of the cell

Interstitial

Minute spaces between phospholipids. In order to pass through, atoms must be very tiny and non polar.

Transmembrane

across the membrane

Transport proteins

A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane.

Channels

Protein tunnels- aquaporin channels- where water passes. Passive transport

Gates

Blocks channels. Gates are opened by something attaching to them and causing a conformation change. Passive transport

Carrier proteins

a protein that transports substances across a cell membrane. Passive transport

Endocytosis

Object/molecule moves into cell from outside

Exocytosis

Object/molecule moves from inside to outside the cell

Phagocytosis

Cytoplasm absorbs object. Often used by white blood cells on pathogens.

Hypotonic

Cells flooding. Greater concentration of water outside the cell than on inside, water rushes in and cell swells up.

Hypertonic

Water concentration is greater inside the cell. Water rushes out and cell size shrinks/shrivels up

Isotonic (Equilibrium)

When the concentration of water is equal on the outside and inside of a cell. Cell remains stable

Turgor Pressure

The pressure of water against the cell wall, cell wall against water. Doesn't happen in animal cells

Plasmolysis

The plant cell dries up (hypertonic) and pulls cell wall inwards

Water Potential

The 'desire' for water to move from P+A - P+B. Factors include concentration gradients (pressure of solutes) and pressure

Pressure potential for 1atm

0pa

When solute pressure =100%:

0-highest solute potential. Will never be a positive answer