Chapter 9 Review Ms. Parekh

What are the six characteristics of life? They: Are organized Grow and develop Reproduce Respond Maintain certain internal conditions Use energy

Define organisms Things that have all the characteristics of life

What is a cell? Is every organism’s smallest unit of life

What are unicellular organisms? Organisms made of only one cell What are multicellular organisms? Living things that are made of two or more cells

What is development? Changes that occur in an organism during its lifetime

What is reproduction? Reproduction is the process by which one organism makes one or more new organisms What are two different ways organisms can reproduce? Simply by dividing without a mate or with a mate

How many types of stimuli are there and what are they? There are two types: external and internal What are external stimuli? changes in an organism’s environment (ex. Light and temperature) What are internal stimuli? changes within an organism (ex. Hunger and thirst)

What is homeostasis? An organism’s ability to maintain steady internal conditions when outside conditions change Why is maintaining homeostasis important? Maintaining homeostasis ensures that cells and the organism can function normally and remain healthy

For most organisms where does the energy for life come from? The sun

How did Carolus Linnaeus classify organisms? Into two main groups, called kingdoms, based on similar structures

What is the current system of classification called? Systematics How does systematics work? Systematics uses all known evidence to classify organisms, including cell type, how food and energy are obtained

How many domains are there today? There are three domains How many kingdoms are there today? There are six kingdoms

What is binomial nomenclature? A system for naming organisms with two-word scientific name What is a species? a group of organisms that have similar traits and are able to produce fertile offspring What is a genus? a group of similar species

Why are scientific names (binomial nomenclature) important? Scientific names are important because each species has its own scientific name and those names are the same worldwide

What is a dichotomous key? A series of descriptions arranged in pairs that lead the user to the identification of an unknown organism

What is a cladogram? A branched diagram that shows the relationships among organisms, including common ancestors

Who invented the first microscope? Anton van Leeuwenhoek

Who first discovered cells? Robert Hooke with a microscope

What is a compound microscope? A compound microscope is a light microscope that uses more than one lens to enlarge images up to 1,500 times their original sizecompound microscopelight microscope

What is an electron microscope? An electron microscope can magnify an image up to 100,000 times or moreelectron microscope

What are the two types of electron microscopes? Scanning electron microscope (SEM) Transmission electron microscope (TEM)

What are some uses of microscopes? In surgery, to investigate forensic evidence from a crime scene, and to study fossils.