Transcript Power Point #3 - cell and organization of living systems

TAKS presentation for Spring
2007
Cells and organization of living
systems
Organization of living systems
• All matter made of atoms
• Atoms organized into molecules
• Molecules organized into cells (Living things are
made of cells)
• Cells organized into tissues
• Tissues organized into organs
• Organs organized into organ systems
• Organ systems organized into organisms
Two types of cells
• Prokaryotic cells
• Eukaryotic cells
Prokaryotic Cells
• Lack nucleus and most
other organelles (structure
within cell – performs
specific function)
• Include Eubacteria and
Archaebacteria
• Archaebacteria – ancient
bacteria
• Eubacteria – true bacteria
• Good bacteria and
pathogenic bacteria
Eukaryotic cells
• Have nucleus and other organelles
Organelles in Eukaryotic cells
• Nucleus – contains DNA; command center of cell
• Mitochondria – found in all eukaryotes – breaks
down food molecules (i.e. – glucose) to release
energy (cellular respiration) Equation for cellular
respiration: C6 H12O6 + 6O2 6CO2 + 6H2O +
ATP
• Ribosomes – where proteins are made
• Endoplasmic reticulum – path along which
molecules move from one part of the cell to
another
• Golgi apparatus – processes and packages
substances produced by the cell
• Lysosome – digests molecules, old organelles, and
foreign substances
• Cilia and flagella – propel cells through the
environment; move materials over cell surface
• Vacuole – storage of water, waste, and/or enzymes
• Microfilaments and microtubules – forms
cytoskeleton of cell for support, movement, and
division of cells
• Chloroplast – found in cells of plants and some
protists – use energy in sunlight to make the sugar
glucose (photosynthesis). Glucose fuels all life’s
processes (plant and animal).
• Cell wall – (plants) supports/protects cell
Plant and Animal cells
How cells keep themselves alive
• Maintain stable internal environment homeostasis
Ways to maintain homeostasis
• Passive transport – no ATP
used
– Diffusion
– Osmosis
– Facilitated diffusion
• Carrier proteins
• Ion channels
• Active transport – ATP
used
– Carrier proteins
• Cell membrane pumps
(sodium-potassium)
– Endocytosis
– exocytosis
Interdependence
• In multicellular organisms cells work
together in organs and organ systems to
help one another maintain homeostasis
Organ Systems
• Circulatory – transports oxygen and nutrients to
cells and carries wastes away from cells
• Respiratory – moves oxygen into the body and
carbon dioxide out of the body
• Digestive – breaks down food and absorbs
nutrients
• Nervous – detects changes outside and inside your
body and controls the way your body responds to
these changes
• Skeletal – movement, protection, shape, support,
storage of minerals and produces blood cells
• Muscular – movement, posture, and production of
heat
• Endocrine – produces chemical messengers called
hormones; some hormones help to maintain
homeostasis while others control development and
growth
• Integumentary – forms protective barrier around
body, prevents water loss, controls body
temperature, and gathers information about your
surroundings
• Immune – protects body from infection
• Lymphatic – takes fluid from the spaces
between cells and returns it to the
circulatory system; filters bacteria and other
microorganisms from this fluid
• Reproductive – males – sperm production;
females – eggs
• Excretory – removes wastes from the body
and helps maintain homeostasis