AP Bio Unit 3: Cell Structure and Function

Ribosomes

These cellular structures comprise rRNA and proteins. They synthesize proteins according to mRNA sequences.

They are present in all living things, but they differ throughout.

Smooth ER

This cellular structure is in charge of detoxification and lipid synthesis

Rough ER

This cellular structure compartmentalizes the cells and is studded with ribosomes that make proteins

Golgi Apparatus

This cellular structure is in charge of the correct folding and chemical modification of newly synthesized proteins, as well as their packaging. It gets proteins from the rough ER and folds them into the correct shape.

Vesicles

These are structures in a cell enclosed by a lipid bilayer and transport materials within the cell

Mitochondria

These cellular structures power the organism by making ATP

They are in charge of aerobic respiration and use oxygen

They have a double membrane, with the outer being smooth and the inner folded (more surface area)

Chloroplasts

These are found in photosynthetic algae and plants. They have lots of surface area for light reaction and make carbohydrates from sunlight (grana, stoma)

Vacuole

This organelle is used for storage

It is a membrane-bound sac

It has many functions in plants (it is larger there as well)

Helps maintain turgor pressure

Endosymbiosis

A process that mitochondria and chloroplasts once experienced: ancestral cells engulfed organelles to form ancestral eukaryotic cells

Fluid Mosaic Model

This model implies that the phospholipid membrane is a fluid structure with various proteins attached to a double phospholipid layer. There is lots of lateral movement caused by heat, enabling charged molecules to enter

Hydrophilic

The phosphate head is _______. It is polar.

Hydrophobic

The phosphate tail is _____. It is nonpolar

Passive Transport

A type of membrane transport that does not require energy to move substances across cell membranes. It moves with the concentration gradient

Active transport

This type of transport allows molecules to move against the concentration gradient and requires energy in the form of ATP to work

Signal Transduction

A “lock and key” mechanism —> a hormone binds to a receptor and a signal is sent into the cell

Channel Protein

This is a type of protein that serves as a pathway for molecules to get inside the cell through the phospholipid bilayer

Carrier Protein

A type of protein that helps with facilitated diffusion and active transport.

Simple Diffusion

A type of diffusion that happens when non-polar molecules can pass through the phospholipid bilayer

Facilitated Diffusion

A process when molecules get through the phospholipid bilayer with the aid of a protein

Endomembrane System

This system is responsible for the following process: Protein making instructions go to the rough ER for translation and making. It releases an unfinished glycoprotein. The golgi body refines and packages the proteins into the correct shape and the vescicles carry it out. Vesicles fuse with the cell membrane or go to the cell surface to get secreted.

Lysosomes

An organelle found in the cytoplasm responsible for the recycling of waste

Non-polar

ONLY these types of molecules are able to pass through the phospholipid bilayer when they are any size.

small polar

(small/large) (polar/nonpolar) molecules can pass through the phospholipid bilayer

Hydrophilic

Channel proteins are _______

Hydrophobic

Carrier proteins are ______

Hypertonic

This environment is when there is more solute outside of the cell than inside. Water flows out of the cell. The solution has a lower water potential than the cell.

Hypotonic

This environment is when there is more solute inside the cell than outside. Water flows into the cell. The solution has a higher water potential than the cell

Isotonic

This environment is when there is an equal amount of solute inside and outside of the cell. Water does not move in or out and the water potential is equal

Lysed

An animal cell is _____ when it is in a hypotonic solution, water enters, and it increases in size and pressure

Shriveled

An animal cell is ______ when it is in a hypertonic solution, water leaves, and the cell decreases in size

Normal

An animal cell is _____ in an isotonic solution, where water enters and exits equally

Turgid

Another word for normal. When a plant cell is inside a hypertonic solution, it expands and is ____.

Flaccid

When a plant cell is in an isotonic solution, water freely enters and exits and the cell is ________

Plasmolyzed

When a plant cell is in a hypertonic solution, water exits and the cell deforms, becoming ______. The plasma membrane shrinks away from the cell wall.

Compartmentalization

This feature allows several activities to happen at once in a cell thanks to membranes (like cubicles in an office). It leads to greater cell complexity and efficiency

Aquaporin

Integral membrane proteins that serve as channels in the transfer of water, and in some cases, small solutes across the membrane. (aka water channels). They are very hydrophillic outside and hydrophobic inside