Bio ch 4 and 5

chromosomes

are condensed chromatin

light microscopes

view animal cells 10-100 µm

electron microscopes

Proteins and viruses are approximately 10-100 nm

rough and smooth ER

Proteins are synthesized by ribosomes located on the rough endoplasmic reticulum (ER), while lipids are synthesized by the smooth endoplasmic reticulum (ER).

Bulk transport

A type of bulk transport where molecules move out of a cell via secretory vesicles is called exocytosis. A type of bulk transport where molecules move into a cell via vesicles is called endocytosis. The bulk transport of large materials such as food particles into the cell is referred to as phagocytosis, while the bulk transport of liquids into the cell is referred to as pinocytosis

extracellular matrix

A(n) extracellular matrix (ECM) is a meshwork of fibrous proteins and polysaccharides. Two well-known proteins are collagen, which resists stretching, and elastin, which gives the resilience. The role of polysaccharides is to direct the migration of cells during development. A tissue's extracellular matrix (ECM) can vary greatly, from flexible cartilage to rigid bone, depending on the types and arrangement of proteins present.

cell wall

All plant cells have a cell wall made up of noncellulose and cellulose fibrils that allow for both flexibility and strength. Living cells are connected through plasmodesmata, which are long membrane-lined channels that pass through the cell wall. The plasmodesmata allow only water and small solutes to pass freely, while cytoplasmic strands allow other materials to flow through.

cytoskeleton 3

Although they provide cells with structure, the fibers of the cytoskeleton assemble and disassemble rapidly and result in cells changing shape from one moment to the next. A motor protein that functions alongside actin to allow for cell movement is myosin. Two other motor proteins, kinesin and dynein, move along microtubules to help with organelle movement.

measurements

Because of this, they are often measured in micrometers (µm), which are 1000 times smaller than a millimeter (mm), or in nanometers (nm), which are 100,000 times smaller than a millimeter!

Cellular respiration

During cellular respiration, mitochondria complete the breakdown of carbohydrates to produce energy that is used to build ATP molecules. This process requires oxygen and carbohydrates, and produces carbon dioxide and water. During photosynthesis, chloroplasts capture solar energy and use it to convert water and carbon dioxide to carbohydrates.

ATP

The adenosine triphosphate (ATP) molecule is composed of the nucleotide adenosine, the sugar ribose, and three phosphate groups. Our bodies use up to 99 pounds of adenosine triphosphate (ATP) every day in order to carry out their activities.

product, substrate, enzyme examples

In scenario 1, lactase is the enzyme, lactose sugar is the substrate, and the simple sugars are the product. In scenario 2, DNA polymerase is the enzyme, the nucleotides are the substrate, and the newly grown strand is the product. In scenario 3, rennin is the enzyme, milk is the substrate, and curds and whey are the product of this reaction.

plasma membrane

In the outer layer of the membrane, the hydrophilic head points outward towards the external environment. In the inner layer of the membrane, the hydrophilic head points inward towards the internal environment. This means the hydrophobic tails point toward each other in the center of the plasma membrane.

stuff in pm

Molecules of cholesterol are embedded within the membrane to give it fluidity, and proteins are embedded within the membrane to aid in the transport of molecules.

cytoskeleton 1

Often referred to as the "bones and muscles" of an animal cell, the cytoskeleton functions in movement, such as vesicle transport of materials, and support, determining a cell's shape.

CR 2

The byproducts from cellular respiration, carbon dioxide and water, are the very molecules that the chloroplasts require to build carbohydrates. In turn, photosynthesis produces oxygen and carbohydrates that are used in cellular respiration.

cytoskeleton 2

The cytoskeleton is made of three types of protein fibers: actin filaments, which serve to support the cell itself; intermediate filaments, which serve to support the nucleus and plasma membrane; and microtubules, which serve to maintain the shape of the cell and aid in organelle movement.

CHAPTER 5: 2nd law of thermodynamics

The second law of thermodynamics states that energy is lost when it is converted from one form to another, often in the form of heat. As cells go through transformations, they increase the total entropy of the universe, resulting in a decrease in available energy. For example, photosynthesis in plants requires an energy input to turn carbon dioxide and water into glucose because there is a decrease in entropy.

cell size

This means that smaller cells, not larger cells, have an adequately sized membrane to accomplish this movement. Because of this, actively metabolizing cells are much smaller than nonactive cells. As cell size decreases the surface area increases.

Enzyme inhibitors

This process can be beneficial as in the case of penicillin, which is a poison for bacteria that may infect the human body. Conversely, this process can be detrimental, as in the case of cyanide, which prevents the enzyme cytochrome C from producing ATP and is a poison to humans. Most enzymes within cells are regulated by feedback inhibition, where substrates compete with other substances for the enzyme's active site.

1st law

energy cant be created or destroyed

tight junctions

found in kidney tubules tight barrier for cells attach cells through plasma membrane proteins

Cilia and flagella

hairy or stiff aid in movement of cell and materials of body

adhesion junctions

intercellular fillaments join internal cytoplasmic plaques together found in bladder, heart, and stomach cells allow sturdy, yet flexible sheets of cells

Gap junctions

open and close due to proteins in plasma membrane- lined channels allow flow of ions found in heart and smooth muscle cells

some organelle functions

ribosomes - protein synthesis Golgi apparatus - protein alteration and packaging mitochondria - production of cellular ATP lysosomes - cellular digestion

centrioles

right angles major microtube organizing center cell division