Bio 4.4 and 4.5

Chloroplasts fun fact

A granum is a stack of thylakoids. Thylakoids look like poker chips.

Ribosomes

protein synthesis

Smooth ER fun fact

smooth ER gets its name because its outer membrane lacks ribosomes

Rough ER fun fact

rough ER gets its name because its outer membrane has ribosomes

Lysosomes : Describe the function

DIGESTION a membranous sac of hydrolytic enzymes that an animal cell uses to digest (hydrolyze) macromolecules. Carries out intracellular digestion in a variety of circumstances. They use their hydrolytic enzymes to recycle the cell's own organic material (autophagy). Typically enzymes work best in acidic environments Phagocytosis - eats an outside organism Autophagy is the process of sequestering portions of cellular interior (cytosol and intracellular organelles) into a membranous organelle (autophagosome), whereas phagocystosis is its topological equivalent engaged in sequestering cellular exterior. Both autophagosomes and phagosomes mature into acidified, degradative organelles, t

Look at Figure 4.15 on p. 81. Identify all the cell parts required for export of a protein out of a cell.

ER produces membranes and proteins Transport vesicles carry membranes and proteins to the Golgi Other vesicles Lysosomes bring enzymes Vacuoles Golgi apparatus Plasma membrane and plasma

Smooth ER :Describe the function

LIPID SYNTHESIS The smooth endoplasmic reticulum is another organelle in eukaryotic cells that synthesizes lipids. This organelle is located near the rough endoplasmic reticulum, and it produces phospholipids and cholesterol that help stabilize the membranes of the entire cell. The smooth endoplasmic reticulum and the rough endoplasmic reticulum both play vital roles in processing and synthesizing compounds for the cell. functions in diverse metabolic processes, which vary with cell type. Examples include: synthesis of lipids, metabolism of carbohydrates, detoxification of drugs and poisons, and storage of calcium ions. Uses enzymes to synthesize lipids Produces sex hormones in testes and ovaries (and steroid hormones secreted by adrenal glands) Detox often occurs in liver cells Stores calcium in muscle cells

Lysosomes fun fact

Lysosomes contain enzymes. When food vacuoles bind with lysosomes digestion occurs.

Golgi :Describe the function

MODIFICATION AND PACKAGING OF PROTEINS THAT WILL BE EXPORTED FROM THE CELL a warehouse for receiving, sorting, and shipping (some manufacturing does occur there - macromolecules). Products of the ER, such as proteins, are modified and stored and then sent to other destinations. Extensive in cells designed for secretion Has two faces: a cis face and a trans face

Mitochondria fun fact

Mitochondria and chloroplasts share similar evolutionary origins

Flagella and Cilia

Movement; Cilia are only found in e cells Hair-like structure attached to a cell, used for locomotion in many protists and prokaryotes. The prokaryotic flagellum differs from the eukaryotic flagellum in that the prokaryotic flagellum is a solid unit composed primarily of the protein flagellin, while the eukaryotic flagellum is composed of several protein strands bound by a membrane, and does not contain flagellin. The eukaryotic flagellum is sometimes referred to as an undulipodium.

Chloroplasts :Describe the function

PHOTOSYNTHESIS (the production of sugars using solar energy) converts energy that cells can use for work; found in plants and algae, sites of photosynthesis; converts solar energy to chemical energy by absorbing sunlight and using it to drive the synthesis of organic compounds such as sugars from carbon dioxide and water

Mitochondria :Describe the function

Production of ATP through the process of cellular respiration converts energy that cells can use for work; site for cellular respiration, uses oxygen to convert ATP by extracting energy from sugars, fats, and other fuels

Vacuoles :Describe the function

STORAGE OF WATER AND OTHER ASSORTED SUBSTANCES SUCH AS PIGMENTS the vacuolar membrane is selective in transporting solutes. Food vacuoles fuse with lysosomes, whose enzymes digest the food. Contractile vacuoles pump excess water Food vacuoles Contractile vacuoles Central vacuoles (in plant cells)

Vacuoles fun fact

The central vacuole is usually the largest compartment in a plant cell Vacuoles are vesicles that contain mostly water and are found in plant cells

Summarize the endosymbiont theory.

This theory states that mitochondria and chloroplasts have similar evolutionary origins. Specifically the theory states that the proposed ancestors of mitochondria were oxygen-using nonphotosynthetic prokaryote cells and the proposed ancestors of chloroplasts were photosynthetic prokaryote cells. The idea is that an early prototype of eukaryotic cell engulfed an oxygen-using nonphotosynthetic prokaryote cell. The engulfed cell became enclosed or endosymbiont (a cell living within another cell). Over time the engulfed and host cells became a single organism, what today we term a eukaryotic cell with a mitochondrium or a nonphotosynthetic eukaryote. In a parallel process, an early prototype of a eukaryotic cell with a mitochondrium engulfed a photosynthetic prokaryotic cell. The engulfed cell became enclosed or endosymbiont (a cell living within another cell). Over time the engulfed and host cells became a single organism, what today we term a eukaryotic cell with chloroplast or a photosynthetic eukaryote.

Nucleus

control of all cell activities (specifically by directing the synthesis of proteins in a cell) usually the larges organelle in a cell The nucleus is the control center of the cell. ... Ribosomes, large complexes of protein and ribonucleic acid (RNA), are the cellular organelles responsible for protein synthesis. They receive their "orders" for protein synthesis from the nucleus where the DNA is transcribed into messenger RNA (mRNA).

Cytoskeleton

e cells only Integrated system of molecules within eukaryotic cells which provides them with shape, internal spatial organization, motility, and may assist in communication with other cells and the environment. Red blood cells, for instance, would be spherical instead of flat if it were not for their cytoskeleton.

Rough ER :Describe the function

place for ribosome synthesis The endoplasmic reticulum is a membrane-bound structure that is a part of every eukaryotic cell. This organelle plays a large role in the synthesis of large, complex proteins and amino acids. The membranes of an endoplasmic reticulum is lined with ribosomes. The ribosomes give the organelle a rough appearance and give the organelle its name. The ribosomes in the rough endoplasmic reticulum manufacture proteins. These proteins are manufactured from chains of amino acids. The proteins then enter the different channels of the organelle and move through the organelle's membranes. As the proteins travel through the organelle, they create small pockets. These pockets pinch off from the organelle and form vesicles. The vesicles transport the proteins to the Golgi complex, where they are processed and distributed to different cells. with the ribosomes on the outer surface of a membrane, rough ER synthesizes proteins which are then secreted. In addition, the rough ER is a membrane factory for the cell; it grows in place by adding membrane proteins and phospholipids to its own membrane. Insulin is secreted by the pancreas into the bloodstream Glycoproteins have carbohydrates bonded to them

Golgi fun fact

the Golgi apparatus consists of stacks of flattened sacs called cisternae which are not physically connected

Vesicles

transport of proteins throughout the cell Vesicles perform a variety of functions. They mostly store, transport or digest cellular products and cellular waste. Since they are separate from the cytosol of the cell they have a completely different internal environment than the cell. For this reason, vesicles can digest cellular machinery and recycle cellular materials. To transport materials into or out of the cell, vesicles fuse with the cell's plasma membrane and release or uptake contents from outside of the cell. In total, there are four main types of vesicles. Vacuoles are vesicles that contain mostly water and are found in plant cells. They transport water in and out of the cell. Lysosomes are vesicles that are found in eukaryotic cells. They are involved in cellular digestion and can also be utilized to recycle damaged cellular organelles. Transport vesicles work primarily with the endoplasmic reticulum and the Golgi apparatus. They transport molecules such as proteins and fats in between these two organelles. Secretory vesicles are the fourth main type of vesicle. They contain materials that need to be excreted from the cell. Most commonly they contain waste products.