Classifying the Diversity of Life



Organisms with prokaryotic cells are separated into two______, Bacteria and Archaea.


____ are the most diverse and widespread prokaryotes.


Most of the prokaryotes known as ___ live in extreme environments, such as salty lakes.


All Organisms with eukaryotic cells are grouped in domain _____.


_____ are diverse collection of mostly single-celled eukaryotes, which are sorted into several kingdoms to reflect their evolutionary relationships.


Kingdom ___ consists of multicellular eukaryotes that produce their food by photosynthesis.


Kingdom _____ infludes Eukaryotic organisms that mostly decompose organic wastes and absorb nutrients into their cells.


Kingdom ___ consists of multicellular eukaryotes that obtain their food by ingesting (eating) other organisms.

Scientific inquiry

Scientists use a general process known as ____ to ask and answer questions about nature.

Inductive Reasoning

Using a type of logic known as ______, a generalized conclusion can often be drawn from a large number of specificobservations


A(n) ______ is a proposed explanation for a set of observations. It leads to predictions that can be tested by additional observations or by experiments.

Deductive reasoning

______ uses "if..... then " logic to proceed from a general hypothesis to specific predictions of results that can be expected if the general premise is true.


A hypothesis must be testable and ____-- there must be some observation or experiment that could show that it is not true.

Controlled Experiment

A(n) _____ involves both an experimental group and a control group, which are alike except for the one variable that the experiment is designed to test.


A(n) ______ is broader in scope than a hypothesis, is supported by a large body of evidence, and generates many new hypotheses.


Lipids are diverse compounds that are grouped together because they are _____.


A fat molecule is composed of two types of smaller molecules: ______ and fatty acids.

Carboxyl Group

A fatty acid consists of a _______ and a long hydrocarbon chain.

Unsaturated acids

_______ have one or more double bonds in their hydrocarbon chains and are usually found in vegetable oils.

Saturated Fatty Acids

The hydrodcarbon chains of ______ are not kinked, and thus pack closely together, making animal fats solid at room temperature.


_______ are a major component of cell membranes. They form a bilayer with their hydrophobic tails mingling together and their hydrophilic heads facing the watery environment on both sides of the membrane.


_____ are lipids with a structure consisting of four fused rings. Many sex hormones are made from this type of lipid.


Nucleic acids are polymers of _____.

Nitrogenous Base

The monomers of nucleic acids consist of a phosphate group, a five-carbon sugar, and a ______.


provides directions for its onw replication. It also directs cell activities by providing instructions for building proteins.


A polynucleotide has a repeating ____ backbone.

Double Helix

The structure of DNA is a _____, held together by the complementary base-pairing of cytosine with guanine, and adenine with thymine.


RNA usually consists of a single ____ strand.