ch 3 - quick check Flashcards
what is the molecular composition of the plasma membrane of the cell?
The plasma membrane is two layers that include phosphate-containing fat molecules called phospholipids, which form a fluid framework, and another kind of fat molecule called cholesterol, which assists in the stabilization of the phospholipid molecules to prevent breakage of the plasma membrane. Protein molecules are also embedded within the plasma membrane.
what is cytoplasm? what is contained within cytoplasm?
The cytoplasm is the internal living material of cells. It contains organelles such as ribosomes, endoplasmic reticulum, Golgi apparatus, mitochondria, lysosomes, and centrioles.
what are the primary organelles of the cell?
cytoskeleton
ribosomes
endoplasmic reticulum
golgi apparatus
mitochondria
lysosomes
centrosome
centrioles
microvilli
cilia
flagella
what is the function of the organelle, Cytoskeleton?
Internal framework of the cell
what is the function of the organelle, ribosomes
Manufacture enzymes and other proteins and are often called “protein factories”
what is the function of the organelle, endoplasmic reticulum (ER)?
Network of connecting sacs and canals that carries substances through the cytoplasm
what is the function of the organelle, golgi apparatus?
Collects chemicals into vesicles that move from the smooth endoplasmic reticulum to the plasma membrane (called the “chemical processing and packaging center”)
what is the function of the organelle, mitochondria?
Involved with energy-releasing chemical reactions (cellular respiration) and are often called the “power plants of the cell”
what is the function of the organelle, lysosomes?
Eat microbes, and the membrane has enclosed packets containing digestive enzymes that promote hydrolysis; often called “digestive bags”
what is the function of the organelle, centrosome?
Serves as the microtubule-organizing center of the cell. It is a region of cytoplasm near the nucleus of each cell. It also plays a role in forming and organizing the cell’s cytoskeleton, including some of the cell’s outward extensions.
what is the function of the organelle, centrioles?
Paired organelles found within the centrosome. Each centriole is composed of microtubules that play an important role in forming a tapered framework or “spindle” that moves chromosomes during cell division.
what is the function of the organelle, microvilli?
Small, fingerlike projections of the plasma membrane of some cells. They increase the surface area of the cell and increase its ability to absorb substances.
what is the function of the organelle, cilia?
Extremely fine, hairlike extensions on the exposed or free surfaces of cells. Cilia act like an insect’s antennae, allowing the cell to sense its surroundings such as the cilia in the taste buds of the mouth that allow us to detect different chemicals by taste.
what is the function of the organelle, flagella?
Projections extending from the cell surface. In humans, the only example of a flagellum is the “tail” of the male sperm cell.
which two kinds of cell structures contain DNA?
Chromatin and chromosomes
what is the difference between a passive transport process and an active transport process?
The difference is that active transport requires ATP and passive transport does not.
briefly explain the following primary passive transport process: diffusion
Diffusion: A trend of movement of particles down a concentration gradient. This movement occurs from an area of high concentration toward an area of lower concentration.
briefly explain the following primary passive transport process: osmosis
A special case of passive transport. In many ways it is similar to diffusion, but it is thought to involve unique mechanisms at the pores of cell membranes. Water moves into a space, but there is no exchange of solutes. Instead a change in fluid pressure may result that is called osmotic pressure.
briefly explain the following primary passive transport process: dialysis
Some solutes move across a selectively permeable membrane by diffusion, and other solutes do not. This results in an uneven distribution of various solutes. This principle is used as a medical procedure (dialysis) when a kidney is not functioning properly.
briefly explain the following primary passive transport process: filtration
The movement of water and solutes through a membrane as a result of a pushing force that is greater on one side of the membrane than on the other side. This force is called hydrostatic pressure. Filtration always occurs down a hydrostatic pressure gradient.o
how does an ion pump work? is it an active or passive transport process?
The ion pump uses energy from ATP to actively move ions across cell membranes against their concentration gradient. It is an active process.
how do phagocytosis and pinocytosis differ?
Phagocytosis is the process that allows a cell to engulf and “eat” relatively large particles. An example - white blood cells. to destroy bacteria and debris from tissue damage.
Pinocytosis is an active transport mechanism used to incorporate fluids or dissolved substances into cells by trapping them in a pocket of plasma membrane that pinches off inside the cell.
how do genes determine the structure and function of the body?
Genes are specific segments of base pairs in a chromosome. Genes direct the synthesis of one kind of protein molecule that may function in a certain manner.
where is genetic information stored in the cell?
Nucleus
