Biology Unit 2 Cell Structure

Prokaryotic

Single celled organisms, lack membrane bound organelles

Eukaryote

Have membrane bound organelles, more complex

What do all cells have

Plasma Membrane, Cytoplasm, Genetic Material, Ribosomes

Plasma Membrane

Responsible for movement in and out of the cell, mosaic of components (fluidity)

What are the two types of transport mechanisms

Active and Passive

Passive transport

Does not require ATP, High concentration to lo

Active transport

Requires protein and ATP, Low concentration to high

What is active transport mainly for

Charged molecules

Large Molecules

Bulk Transport

Concentration gradient

The difference in solute concentration in and out of the cell

Increased difference in concentration equals what?

Faster rate of diffusion

What are the two types of diffusion

Diffusion

Facilitated Diffusion

Diffusion

Single substance moves down its concentration gradient

Facilitated diffusion

Substance moves down the concentration gradient, requires a transport protein

Faster rate of diffusion

Increased Temperature

Increased surface area : volume ratio

Slower rate of diffusion

Increased mass of molecule

Increased membrane thickness

Increased length across membrane

Channel Proteins

Create hydrophilic holes in membranes for molecules to move down concentration gradient

Aquaporins

channel proteins specifically for water

Carrier Proteins

Physically must bind to the solute in order to move it across membrane

Osmosis

Diffusion of Water down its concentration gradient, Important for cell function, Passive

Hypertonic solution

Higher concentration outside the cell (Water moves out)

Hypotonic Solution

Lower concentration outside the cell (Water moves in)

Isotonic Solution

Same concentration outside cell

What happens when a cell expands to much

Cell Lysis

What happens when a plant cell shrinks too much

Plasmolysis

What are the three types of transport proteins

Uniporter

Symporter (Co Transport)

Antiporter (Co transport)

Uniporter

Movement of one molecules

Symporter

Both molecules go in same direction

Antiporter

Molecules go in different directions

What are bulk transporters

Endocytosis and Exocytosis

The two types of endocytosis

Phagocytosis and Pinocytosis

Phagocytosis (Cell Eating)

Taking in large, undissolved molecules, Vesicle merges with the lysosome to form a phagolysosome

Pinocytosis (Cell Drinking)

Taking in extracellular fluid

Exocytosis

Removing material from the cell

Cytoplasm

Gel that holds the cell together

What kind of protein filaments is the cytoskeleton made up of?

Microfilaments

Intermediate filaments

Microtubules

Microfilaments (Actin Filaments)

Narrowest filament, Help with cell movement and shape

Intermediate filaments

Middle sized, purely structural, anchors the nucleus and other organelles in place

Microtubules

Widest filament, help cells resist compression, provides vesicle tracks, work in mitosis by moving chromosomes around

Where does protein synthesis (translation of mRNA) occur

Ribosomes

What are ribosomes composed of

Large and small subunits

Free floating Ribosomes

Make proteins for within the cell

Rough ER Ribosomes

Make proteins for outside the cell

What do prokaryotes have in their cell walls

Peptidoglycan

Which cells are bigger Prokaryote or Eukaryote

Eukaryote

What shape is the DNA of prokaryotes

Circular

Where do prokaryotes complete DNA replication, transcription, and translation

All in the same place

Flagella (Prokaryote)

Allow for movement (rotary motion)

Magnetosomes (Prokaryote)

Respond to magnetic forces

Pili/Fimbriae for Prokaryotes

Help with attachment and sexual reproduction (not all prokaryotes have it)

What shape is the DNA for eukaryotic cells

Linear

Nucleus

Holds your DNA, where DNA replication and transcription occur

What is the nuclear structure composed of

Nuclear Envelope

Chromatin

Nucleolus

Nuclear envelope (membrane)

Double layer of phospholipids that has nuclear pores that allow molecules in and out of the nucleus

Chromatin

Make up chromosomes and is only distinguishable during cell replication

Nucleolus (Dark Spot)

Holds the DNA that encodes rRNA

Rough ER

Has ribosomes, helps with production and movement of protein

Smooth ER

Lipid synthesis, metabolism and hormone synthesis (fatty acids)

Where does cellular respiration take place?

Mitochondria

Why is the Mitochondria considered the powerhouse of the cell

Creates ATP by breaking down sugars

Who do you inherit Mitochondria from

Maternal Parent, has DNA that get’s replicated just like nuclear DNA

Golgi Apparatus

Takes protein from rough ER, processes them more and then transports them

Peroxisomes

Process reactive oxygen species necessary for metabolism

Vesicles

Transport material into and out of cell

Vacuoles

Storage of waste (animal cells) or water (plant cells)

Can eukaryotes have flagella or cilia

Yes, but different functions, for movement

Centrosomes

Initiates cell division

Lysosome

The digestive component of a cell, breaks down molecules for nutrients

What digestive enzymes to lysosome use

Lysozymes

What are the specialized features in Plant Cells

Cell Wall

Chloroplasts

What is the cell wall made of

Cellulose and Chitin for fungi

Chloroplasts

Where photosynthesis occurs, Has DNA from cyanobacterial ancestors

What do all modern photosynthetic organisms have

chlorophyll -A

Stroma

Fluid within chloroplasts

Thylakoid

Stacked up to form a grana

What is inside a thylakoid

Lumen, photosynthesis occurs in here

Can prokaryotes still be photosynthetic

Yes, they don’t have chloroplasts, but they can have thylakoids