Unit 3 Organizing Life

Which pair of organisms listed in the table are most closely related?

• the dog and the robin

• the robin and the whale

• the whale and the dog

• the beetle and the robin

Annamarie is using a microscope to look at a single-celled organism. While observing the organism she sees chloroplasts, a nucleus, and several other membrane-bound organelles including a flagellum that helps the cell to swim back and forth across the microscope slide. She estimates its size to be over 100 micrometers (0.1 mm). She draws a diagram of what she sees in her notebook that looks like the organism pictured below. .Which statement correctly describes how Annamarie knows that this organism she is observing belongs in the Eukarya domain?

• It has a nucleus, and all cells in the Eukarya domain have a nucleus

• It has chloroplasts, so it must be a plant cell, and all plant cells are in the Eukarya domain.

• It is swimming, so it must be an animal cell, and all animals are in the Eukarya domain.

• It is over 100 micrometers (0.1 mm) in size, so it must be in the Eukarya domain.

A prokaryote is an organism that is composed of a single cell that does not include a nucleus or other organelles enclosed within membranes. All bacteria are prokaryotes. Which of the following correctly identifies the hierarchal organization in bacteria from smallest unit to largest?

• cell → molecules → atoms

• molecule → cells → tissues

• cells → tissues → organs

• atoms → molecules → cell

Both a single celled organism, like a euglena, and a multicellular organism, like a butterfly, must get rid of waste. Why do all cells need to release waste?

• All cells must release waste to extract energy from food.

• All cells must release waste to feed the cells around it.

• All cells must release waste to maintain homeostasis.

• All cells must release waste to reproduce.

Which of the following statements correctly identifies the general characteristics of organisms in a domain?

• Domain Protista includes single-celled and simple multicellular organisms that have plantlike or animal-like characteristics

• Domain Eukarya include single-celled organisms that lack nuclei

• Domain Bacteria includes multicellular organisms that make their own food

• Domain Archaea includes single-celled organisms that can be found in hot springs and thermal vents

Some organisms have different common names in different parts of the world, but all organisms are given only one scientific name. Which statement describes how the scientific name of an organism is written?

• It is written with quotation marks around it.

• It is written in English.

• It is written as genus and species.

• It is written as kingdom and phylum.

Jelal subscribes to a nature magazine. An article about the classification of mammals includes the following table. Which of the following is a conclusion that Jelal can draw from the table?

• The organisms belong in the same genus.

• The organisms do not have a common ancestor.

• The organisms are members of Domain Archaea.

• The organisms lack any shared DNA.

Which statement explains why scientists classify organisms into groups based on shared characteristics?

• Classification helps scientists understand how the parts of a cell work together.

• Classification helps scientists understand the chemical reactions that are necessary for organisms to live.

• Classification helps scientists understand how ecosystems can be organized into levels of complexity.

• Classification helps scientists understand the relationships between different species.

Eukaryotes are classified into four kingdoms according to certain characteristics. The diagram below shows some characteristics of the four kingdoms. Which of these is the plant kingdom?

• Kingdom 4

• Kingdom 3

• Kingdom 2

• Kingdom 1

Provided is a dichotomous key for determining the kingdom of an organism. In what kingdom would a multicellular organism be classified if it cannot make its own food and is not capable of movement?

• Animalia

• Fungi

• Plantae

• Eubacteria