what does it mean to say something is alive?
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What does it mean to say something is ALIVE?. 8 Characteristics of Living Things. Made of cells Reproduce Based on a universal genetic code Grow and develop Obtain and use materials and energy Respond to their environment Maintain a stable internal environment - PowerPoint PPT PresentationTRANSCRIPT
What does it mean to say something is ALIVE?
8 Characteristics of Living Things
• Made of cells• Reproduce• Based on a universal genetic code• Grow and develop• Obtain and use materials and energy• Respond to their environment• Maintain a stable internal environment• Taken as a group, living things change over time
Made of CellsLiving things are…
Living things have…
The ability to reproduce
Based on a Universal Genetic
Code: DNA
Living things are…
Grow and Develop
Living things …
Obtain and Use Energy - METABOLISMLiving things …
Respond to the
Environment –Stimulus
Living things…
Maintain a stable internal
environmentHOMEOSTASIS
Living things …
Evolutionary Adaptation: Species change over time
Living things undergo…
Cell Structure and Function
Look at the words below. Can you order them from simple to most complex?
BiomoleculesOrganelle Cell Tissue Organ Organ System
Organism
What we will be looking at the next few weeks
The Cell TheoryAll living things are composed of
cells. If its not made up of at least one cell, it is NOT living!
Cells carry on similar functions like obtaining energy and removing waste
Types of CellsTwo kinds of cells depending on
whether they have a nucleusProkaryote
Eukaryote
Genetic material
ProkaryotesUsually small and
simple
Genetic material (DNA) is not contained in a nucleus
The ONLY prokaryotes in the world are BACTERIA.
Prokaryotic Cells
EukaryotesUsually larger and
more complex than prokaryotes.
May be unicellular like an amoeba or multicellular like a plant
Contain dozens of specialized structures called organelles.
Includes protists, fungi, plants and animals.
Eukaryotic cell structureTwo major parts:
NucleusCytoplasm-portion of the cell outside the
nucleus
Eukaryotic cells
Nucleus-The control centerFunction:
Contains almost all of the cell’s DNA for coding proteins and other molecules.
DNA is found on chromosomes which contain genetic information.
Nucleus-The control centerStructure:
Surrounded by a double membrane called a nuclear envelope. It is dotted with many pores (holes) to allow materials (RNA, proteins, etc) in and out of the nucleus.
Small internal region called a nucleolus where ribosomes are made.
RibosomesFunction:
Site of protein assembly.
Structure:Small pieces of RNA
and protein found throughout the cell.
Endoplasmic ReticulumFunction:
Site where lipid parts of cell membrane are made, along with proteins and other materials to export from the cell.
Structure: Rough ER- has ribosomes
on surface to assemble proteins
Smooth ER-NO ribosomes on surface
Golgi ApparatusFunction:
Modify, sort, and package proteins and other materials from the ER for storage in the cell or release from the cell. It puts the finishing touches on proteins.
Structure: Stack of closely
packed membranes
You have 3 minutes to compare your notes with a neighbor. Be sure to ask questions and fill in any blanks you may have in your notes at this time.
Lysosomes-The Clean Up CrewFunction:
Breakdown of lipids, carbohydrates and proteins into small molecules to be used by the rest of the cell
Breakdown used up organelles
Get rid of all “stuff” in the cell
Structure: Small, filled with
enzymes
Vacuoles - StorageFunction:
Stores water, salts, proteins and carbohydrates
Structure:Sac-likePlant cells have one
large central vacuoleAnimal cells have
many small vacuoles
Mitochondria - EnergyFunction:
Convert chemical energy in food into materials easier for the cell to use.
Structure: Enclosed by two
membranes with the inner membrane folded up.
Contains it’s own DNA (unlike other organelles) that is identical to your mother’s!
Chloroplasts – Energy in Plants Function:
Captures energy from the sun (solar energy) and changes it into food (chemical energy) for plants (photosynthesis)
Structure: Surrounded by two
membranes Contains own genetic
information like mitochondria
Contains green pigment called chlorophyll
Not found in animal cells!
With your neighbor, list similarities and differences between mitochondria and chloroplasts. Be prepared to share with the class.
Cytoskeleton- structure and support
Function:Helps maintain cell
shape Helps with
movement of the cell (i.e. flagella and cilia)
Structure:Two types:
microfilaments and microtubules
Cell MembraneFunction:
Regulates what enters and leaves the cell
Provides protection and support
Structure: Double membrane
called a lipid bilayer Flexible structure that
forms a strong barrier between the cell and its surroundings
Cell WallFunction:
Provides support and protection for the cell
Structure:Lies outside the cell
membraneFound in plants,
algae, fungi and many bacteria
NOT FOUND IN ANIMAL CELLS!
Individually, write down 3 differences between plant and animal cells.