AP Bio- Unit 2: Cell structure and function

PC: (10/1)

Cells

Basic structural and functional units of all life

Organelles

Membrane bound structures in eukaryotes

Eukaryote

Cell present in animals, plants, and fungi

• DNA is located in the nucleus and contains membrane-bound organelles

Prokaryote

Cell present in bacteria

• DNA is in the nucleus

• Generally smaller than eukaryote cells

Organelles: Nucleus.. and nucleolus

Contains chromosomes (nucleus). Nucleolus is found in nucleus

Organelles: Golgi Apparateus

Receives, transports, packs, and adds tags to vesicles

• Contains cisternae

• Trans-face(sending off) vs Cis-Face (recieving)

• Lysosome synthesis

Cisternae

Flattened membrane sacs in the Golgi

Organelles: Smooth ER

Contains no ribosomes. Synthesizes lipids, metabolizes carbs and detox’s cells

• located in the cytoplasm of eukaryotic cells

Organelles: Rough ER

Contains ribosomes bound to the ER membrane

Peroxisomes

Breaks down fatty acids and detoxifying harmful substances

• Has membrane bound metabolic compartments that catalyze reactions that make H2O2

• similar to lysosomes

Organelles: Mitochondria

Cite of cellular respiration. Highly folded to greatly increase its surface area → more protein housed → more chemical energy

• Has an inner membrane and mitochondrial matric

• Krebs cycle

• ATP synthesis

Kreb’s cycle

Contains a series of chain reactions that cells use to release energy stored in food and make usable cellular energy.

• happens in the mitochrondria

Organelles: Chloroplasts

Located in plants only. Specialized organelles in photosynthetic organisms

• Photosynthesis occurs here

• Calvin cycle

Photosynthesis

Plants and certain bacteria convert light energy into chemical enegry

• Happens in the chloroplasts

Thylakoids

Membranous sacs/ compartments that can organize into stacks called grana in the chloroplasts

Grana

Light dependent reactions occur here in the chloroplast

• stacks of thylakoid

Light Reactions

The light-dependent reactions of photosynthesis convert solar energy into chemical energy (ATP and NADPH)

• occur in the thylakoid membranes of chloroplasts.

Stroma

Fluid around Thylakoids in chloroplast

Calvin Cycle

A set of light-independent chemical reactions in photosynthesis that converts carbon dioxide into sugar

• Happens in the stroma (chloroplasts)

Why is chlorophyll important to plants?

Because the pigments help capture light energy during photosynthesis, protect cells from excess light damage, and provide color to attract pollinators

Cilia

Permits cell mobility in a eukaryotic cell

Flagella

Permits cell mobility in a prokaryotic cell

Actin

A vital, highly conserved globular protein that forms microfilaments in the cytoskeleton of all eukaryotic cells and thin filaments in muscle fibers

Organelles: Ribosomes

Compromised of ribosomal RNA and protein

• Synthesizes proteins

• “protein factory” of the cell and read genetic info

Autophagy

When cells clean out damaged parts and recycle them into reusable energy and building blocks

Microtubules

Serves as structural support for the movement of organelles that are interacting with motor proteins

intermediate filaments

Ropelike cytoskeletal fibers that provide mechanical strength and structural support to cells.

Plasma membrane

Flexible, semi-permeable barrier that surrounds all lining cells and separates their interior from the outside environment

Organelles found only in animal cells

Lysosomes, centrosomes, and flagella

Organelles found only in plant cells

Chloroplasts, central vacuole, cell wall, and plasmodesmata

Endomembrane system

A group of membranes and organelles inside eukaryotic cells that work together to modify, package, and transport lipids and proteins

Compartmentalization

Important because it allows for different metabolic reactions to occur in different locations.

• Increases surface area for reactions to occur

• The mitochondria and chloroplast use internal membranes to divide specific chemical reactions and make cellular energy production more efficent

Endosymbiotic theory

Early Eukaryotic cells engulfed a prokaryotic cell and became functional.

• Proof of this is the similarities in mitochondria and chloroplasts

Electron transport chain

A series of protein complexes and mobile molecules embedded in the inner mitochondrial membrane that transfer electrons and pump protons to generate ATP

Order of transport in organelles

1. Nucleus / DNA

2. Ribosome

3. Rough ER: The rough ER packages the protein into a small membrane sac called a transport vesicle, which carries it to the Golgi apparatus.

4. Golgi Apparatus

5. Secretory / Transport Vesicle (from Golgi): The finished protein is packaged into a new vesicle that buds off the shipping side (trans face) of the Golgi apparatus.

6. Cell Membrane

Kreb’s Cycle vs. Calvin cycle

The Calvin cycle builds sugars using energy, while the Krebs cycle breaks down molecules to release energy.