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a. Cells are extremely small, basic units of living matter, from which plants and animals are made of. They consist of
protoplasm, nucleus, and a membrane. A cell is located inside of a semipermeable membrane, which is a colorless matter similar
to soft jelly, suspended in water, and is a chemical mixture of proteins and fats. A semipermeable membrane allows the solvent,
but not the dissolved substance to pass through. For example, if a semipermeable membrane separated fresh water and salt water,
the fresh water would flow into the salt water. A selective permeable membrane features the plasma membrane that maintains
homeostasis within a cell by allowing some molecules into the cell while keeping other out. The plasma membrane is the flexible
boundary between the cell wall and its environment and allows materials such as water an nutrients to enter an waste products
to leave. Within the membrane osmosis occurs. Osmosis is the diffusion of water across a selective permeable membrane depending
on the concentration of solvents on either side of the membrane. Diffusion is the random movement of particles from an area
of higher concentration to an area of lower concentration, resulting in even distribution. Facilitated diffusion is the passive
transport of protein embedded in the plasma membrane. Active transport energy is the expanding process by which cells transport
materials across the cell membrane against a concentration gradient. Passive transport is the movement of particles across
cell membranes by diffusion or osmosis and the cell uses no energy to move particles across the membrane. Transport proteins
are proteins that span the plasma membranes creating a selectively permeable membrane.
b. An enzyme is a protein substance made in living cells that affect chemical reactions within a plant or animal without
being changed itself, and is an organic catalyst; and is used to break down food so that is can be digested. Enzymes need
to be the same temperature, ionic conditions, and pH in its environment or else it becomes denatured. When an enzyme is denatured
it becomes “dead” or no longer working.
c. Prokaryotic cells do not have any internal membrane structures. Prokaryotic cells do not separate different areas of
the cell from each other and make up the smallest single-celled organisms like bacteria. Eukaryotic cells present in all living
things except bacteria. They contain many internal membrane structures. The most important of these structures is the nucleus,
which contains the cell’s hereditary material (DNA). Virus uses are disease-causing, nonliving particles composed
of an inner core of nucleic acids surrounded by a capsid, replicate inside living cells called the host cells. They are nonliving
because they do not carry out respiration, grow, or develop.
d. In the “Central Dogma of Molecular Biology” the information from the DNA in the cell has to be
transported to the rest of the body. However DNA is too big to get out of the semipermeable membrane. So DNA has to be broken
down into RNA or mRNA(transcription), which is small enough to go through the membrane. The information is then transported
to the Ribosomes where proteins are made(translation). Message RNA(mRNA) transports information from the DNA in the nucleus.
e. The endoplasmic reticulum is an organelle in a eukaryotic cell and is the site of cellular chemical reactions and is
arranged of a series of highly folded membranes in the cytoplasm. The golgi apparatus is a flattened stack of tubular membranes
that modifies the proteins. The golgi apparatus sorts proteins into packages and packs them into membrane-bound structures,
called vesicles, to be sent to the appropriate destination. Ribosomes in the cytoplasm are attached to the surface of the
ER, called rough ER, where the function protein synthesis is carried out. Smooth ER are the areas without ribosomes and produces
and stores lipids.
f. Chloroplasts are lens shaped organelles found in leaves and other green organisms. In the green tissue are mesophlyll,
which have 30-40 chlorophylls and are made up of sack like photosynthetic membranes. They then form stacks called grana, thylakoids
then separate the grana from the stroma, the fluid outside the thylakoid. The chloroplasts main function is to trap solar
energy and to use it to form carbohydrates. Chloroplast are also the site of photosynthesis which is the main form of food
source. Photosynthesis is the process that uses the sun’s energy to produce simple sugars. These simple sugars are
then converted in complex carbohydrates, like starches, which store energy. The Calvin Cycle: One molecule of carbon dioxide
is added to one molecule of RuBP to form a six-carbon sugar. This stage is called carbon fixation because carbon is fixed
into a six-carbon sugar. In a series of reactions, the sugar breaks down and is converted to two three-carbon sugar called
phosphoglycereldehycle, PGAL. After three rounds of the cycle, with each round fixing one molecule of CO2, 6 molecules of
PGAL released. 5 of them are rearranged to form 3 molecules of RuBP. The sixth molecule of PGAL is available for making sugars,
carbohydrates, and other organic compounds. Photosynthesis formula
g. Mitochondria are membrane-bound organelles in plant and animal cells that transform energy for the cell. This energy
is then stored in the bonds of other molecules that cell organelles can access easily and quickly when energy is needed. Cellular
respiration is the process where mitochondria break down food molecules to produce ATP, there are three stages: glycolysic,
citric acid cycle, and the electron transport chain. Glycolysic is a seris of chemical reactions in the cytoplasm that breaks
down glucose into two molecules of Pyremic acid. The electron transparent chain is when NADP+ carries energized electrons
to another location in the cell for further chemical reactions.
h. Exemplar Chart
i. Ademosiac triphosphate (ATP) is composed of and adenosive molecule with three phosphate groups attached. ATP is a molecule
in your cells that is a quick source of energy for any organelle in the cell that needs it. The energy is stored in the chemical
bonds of the molecule and used quickly and easily by the cell. Hydrogen ions go into the thylakoid causing a high concentration
gradient across the membrane, H+ ions diffuse and provide energy for making ATP. The coupling of H+ ions to ATP production
is called chemiosmosis.
j. The cytoskeleton is a support structure within the cytoplasm. The cytoskeleton forms a framework for the cell. It is
a changing structure. It can be dismantled in one place and reassembled somewhere else in the cell, changing the cell’s
shape. Microtubulus are thin, hallow cylinders made of protein. Microfilaments are smaller, solid protein fibren. Together
they maintain the shape of the cell and support many organelles and provide space in which materials move within the cell.
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