Science, Ch. 7

Drawing Conclusions - Explain how temperature affects the amount of carbon dioxide that the yeast cells produce.

Yeast cells produce the right amount of carbon dioxide at 37.5 degrees C. When it's too cool, or too warm, the amount of carbon dioxide decreases.

The only way in which viruses are like organisms is...

the way they can multiply.

Interpreting Data - Based on the graph, at what temperature does yeast produce the most carbon dioxide?

37.5 degrees C

pasteurization definition

A process of heating food to a temperature that is high enough to kill most harmful bacteria without changing the taste of the food.

pseudopod definition

A "false foot" or temporary bulge of cytoplasm used for feeding and movement in some protozoans.

mutualism definition

A close relationship between organisms of two species in which both organisms benefit.

symbiosis definition

A close relationship between two organisms of different species that benefits at least one of the organisms.

binary fission definition

A form of asexual reproduction in which one cell divides to form two identical cells.

budding definition

A form of asexual reproduction of yeast in which a new cell grows out of the body of a parent.

Inferring - Use the graph to explain why yeast is dissolved in warm water, rather than in cold water, when it is used to make bread.

A higher temperature produces more carbon dioxide which makes the yeast rise.

Flagellum definition

A long, whiplike structure that helps a cell to move.

asexual reproduction definition

A reproductive process that involves only one parent and produces offspring that are identical to the parent.

sexual reproduction definition

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents.

Protozoan definition

A single-celled microscopic animal-like protist such as an amoeba.

endospore defitition

A small, rounded, thick-walled resting cell that forms inside a bacterial cell.

vaccine definition

A substance used in a vaccination that consists of weakened or killed pathogens that can trigger the immune system into action.

spore definition

A tiny cell that is able to grow into a new organism.

Virus definition

A tiny, nonliving particle that invades and then reproduces inside a living cell.

Which part of a virus determines which host cells it can affect?

A virus can attach to a cell only if the virus' surface proteins can fit those on the cell.

How does an amoeba obtain food?

Amoeba use temporary finger-like extensions which fuse over the food and forms a food-vacuole. Inside the food vacuole, food is broken down into smaller pieces.

What is a heterotroph?

An organism deriving its nutritional requirements from complex organic substances. Like animals, animal-like protists are heterotrophs and most are able to move from place to place to obtain food.

decomposer definition

An organism that breaks down chemicals from wastes and dead organism and returns important materials to the soil and water.

What is an autotroph?

An organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide. Like plants, algae are autotrophs.

Eukaryote

An organism whose cells contain nuclei.

Explain how antibiotics kill bacteria

Antibiotics affect things that bacterial cells have but human cells don't. For example, human cells do not have cell walls while many bacteria do. The antibiotic penicillin works by keeping a bacterium from building a cell wall.

How do the bacteria that live in your intestines help you?

Bacteria help your body break down big food molecules into useable fuel. Bacteria also produce vitamins and help protect the body from diseases.

Why will a certain virus attach to only one type or a few types of cells?

Because the lock-and-key action of a virus is specific. The shape of the surface proteins allows the virus to attach only to certain cells.

Which of the following characteristics describes all protists? A.) They are unicellular, B.) They can be seen with the unaided eye. C.) Their cells have nuclei. D.) They are unable to move on their own.

C.

Which of the following statements about paramecium is correct? A. It has 2 contractile vacuoles that remove excess water from the cytoplasm. B. It uses cilia to move. C. It has two nuclei. D. All of the above.

D. All of the above

How does sexual reproduction occur in fungi?

During mating, the hyphae of two fungi grow together and genetic material is exchanged.

Describe how a hidden virus multiplies.

Each time the host cell divides, the virus's genetic material is copied along with the host's genetic material.

Fungi definition

Eukaryotic organisms that have cell walls, uses spores to reproduce and is a heterotroph that feeds by absorbing its food.

True or false? Plantlike protists are called protozoans.

False. An animal-like protist is called a protozoan.

True or false? Most fungi are made up of threadlike structures called spores.

False. Hyphae are the branching threadlike tubes that make up the bodies of multicellular fungi.

Explain fungi

Fungi are eukaryotes that have cell walls, are heterotrophs that feed by absorbing their food and use spores to reproduce.

How do Fungi reproduce?

Fungi usually reproduce by making spores. The lightweight spores are surrounded by a protective covering and can be carried easily through air or water to new sites.

Which of the following statements about fungus reproduction is true? F. Fungi reproduce sexually by budding. G. Fungi reproduce by making spores. H. Fungi reproduce asexually when two hyphae join together and exchange genetic material. J. Fungi do not reproduce sexually.

G.

How does bacteria release its energy?

It must have a source of food and a way of breaking down the food.

Which of the following statements about viruses is NOT true? F. Viruses can multiply only inside a living cell. G. Viruses have genetic material. H. Virus particles are smaller than bacterial cells. J. Diseases caused by viruses can be cured by antiobiotics.

J.

What are funguslike protists?

Like fungi, funguslike protists are heterotrophs, have cell walls and use spores to reproduce.

What is fungis role?

Many fungi provide foods for people. Fungi play important roles as decomposers and recyclers on Earth. Some fungi cause disease while others fight disease. Still other fungi live in symbiosis with other organisms.

Predicting - Based on the graph, would you expect bread dough to rise if it were placed in a refrigerator? Explain.

No because it would be too cool for carbon dioxide production.

Protist definition

Organisms that are not plants, animals, bacteria or fungi. Protists are a very diverse group of organisms that don't fit into the other groups. They include the protozoans, most algae and often some fungi (as slime molds).

Compare how animal-like, plantlike, and funguslike protists obtain food.

Plant like protists obtain their food by the suns energy. Animal like protists move around. Fungus like protists get their food by moving around occasionally or through photosynthesis.

algae definition

Plantlike protists. A simple nonflowering plant of a large group that includes seaweeds and many single-celled forms. Algae contain chlorophyll but lack stems, roots, leaves and vascular tissue.

Bacteria are...

Prokaryotes. The genetic material in their cells is not contained in a nucleus.

What can you do while you recover from a viral disease?

Rest, drink plenty of fluids, eat well-balanced meals.

What will most likely happen after the virus in the diagram attaches to the bacterial cell? A. The virus will inject its proteins into the bacterial cell. B. The virus will inject its genetic material into the bacterial cell. C. The bacterial cell will inject its proteins into the virus. D. The bacterial cell will inject its genetic material into the virus.

See diagram on pg. 247. B.

Bacteria definition

Single-celled organisms that lack a nucleus.

hyphae definition

The branching, threadlike tubes that make up the bodies of multicellular fungi.

contractile vacuole definition

The cell structure that collects extra water from the cytoplasm and then expels it from the cell.

lichen definition

The combination of a fungus and either an alga or an autotrophic bacterium that live together in a mutualistic relationship.

Once inside a cell, a virus's genetic material takes over many of the cell's functions. What does it do?

The genetic material instructs the cell to produce the virus's proteins and genetic material. These proteins and genetic material then assemble into new viruses.

cilia definition

The hairlike projections on the outside of cells that move in a wavelike manner.

Host definition

The organism that a parasite or virus lives in or on.

Parasite definition

The organism that benefits by living on or in a host in a parasitism interaction.

conjugation definition

The process in which a unicellular organism transfers some of its genetic material to another unicellular organism.

fruiting body definition

The reproductive structure of a fungus that contains many hyphae and produces spores.

True or false? Active viruses enter a cell and immediately begin to multiply.

True

True or false? Bacteria form endospores to survive unfavorable conditions in their surroundings.

True

True or false? During conjugation, one bacterium transfers genetic material to another bacterial cell.

True

Compare and contrast viruses and bacteria with respect to their sizes, structures and methods of reproduction.

Viruses are 100 times smaller than bacteria and require living hosts such as people, plants or animals to multiply. Bacteria are self-reproducing and can reproduce without a host. Viruses can only invade our cells if they have surface proteins that fit receptors like a lock and key. Bacteria use hairy pili to attach. Bacteria uses asexual reproduction.

Describe how bacteria reproduce.

When bacteria have plenty of food, the right temperature and other good conditions, they reproduce a lot. They can reproduce through asexual reproduction or sexual reproduction.

When do bacteria thrive and reproduce frequently?

When they have plenty of food, the right temperature and other suitable conditions.

A lichen is a symbiotic association between...

a fungus and either an alga or an autotrophic bacterium.

bacteriophage definition

a virus that infects bacteria. It's name means "bacteria eater."

All viruses have two basic parts:

an outer coat that protects the virus and an inner core made of genetic material.

Bacteriophages are viruses that attack and destroy

bacteria.

Most bacteria are surrounded by a rigid protective structure called the...

cell wall.

What tasks are bacteria involved in?

oxygen and food production, environmental recycling & cleanup and in health maintenance and medicine production.