7.2: Bacteria

____________ are examples of ___________ bacteria (right). Bacteria that live around volcanic vents or other harsh environments can make their own food without sunlight. They use chemicals to produce their food instead of energy from the sun. This process is called chemosynthesis.

Cyanobacteria, photosynthetic

The average bacterial cell is about ______ times ________ than the average person. Bacteria are not easy to measure using meters, centimeters, or even millimeters

1.5 million, smaller

One of the products of photosynthesis is oxygen. Over hundreds of millions of years, the amount of oxygen in Earth's atmosphere increased. This allowed aerobic bacteria to develop. _________ use ______ for cellular respiration. There are many different species of aerobic bacteria living today.

Aerobic bacteria, oxygen

_______ do not require _______ for cellular respiration. Today, anaerobic bacteria thrive in places that have little or no oxygen, like swamps.

Anaerobic bacteria, oxygen

________are found in extreme environments like ______ in the ocean. They are thought to be the first organisms on Earth. Eubacteria are found almost everywhere else and have a different chemical makeup than archaebacteria.

Archaebacteria , volcanic vents

Some scientists group all bacteria into the Kingdom Monera. Others divide bacteria into two kingdoms, ______ and ________.

Archaebacteria, Eubacteria

Bacteria live on or in just about every material and environment on Earth. They live in soil, water, and air. They are found in the coldest regions of the ______ and even in boiling waters near undersea_______

Arctic, volcanoes.

_______ are the only prokaryotes (cells with no nuclei). All other life forms on Earth are _________.

Bacteria, eukaryotes

_________ are used in many areas of industry. Yogurt and cheese are made with certain types of bacteria. Some important drugs like ______ are made with the help of bacteria. Sewage treatment plants use bacteria to break down waste products. Other bacteria are used in mining and to clean up oil spills. There is a good chance that you've benefitted from bacteria today!

Bacteria, insulin

_________ are an important part of the ________ that all life depends upon. For example, plants need nitrogen to make amino acids, the building blocks of protein.

Bacteria, nutrient cycles

_______ are organisms that consist of a single, ________ cell.

Bacteria, prokaryotic

______are often described according to the _____ of their cells. Rod-shaped bacteria are called bacilli. Ball-shaped bacteria are called cocci. Spiral-shaped bacteria are called spirilla.

Bacteria, shape

_______ are everywhere and some can make you ___. But did you know that many types of bacteria are helpful? In fact, life on Earth depends on them.

Bacteria, sick

Termites have bacteria in their stomach that absorb and break down cellulose. _______ is the compound that makes up_____, a termite's favorite food. The bacteria help the termite get energy and nutrients from wood.

Cellulose, wood

Archaebacteria are found in extreme environments like volcanic vents in the ocean. They are thought to be the first organisms on Earth. _________are found almost everywhere else and have a different _______ makeup than archaebacteria.

Eubacteria , chemical

The average bacterial cell is about 1.5 million times smaller than the average person. Bacteria are not easy to measure using meters, centimeters, or even millimeters. Micrometers (μm) are used to measure them. One micrometer is equal to one-millionth of a meter. The size of bacteria range from 1μm to 5μm. _______ cells tend to be about ten times larger than _______cells (Figure 7.7).

Eukaryotic, bacterial

Rod-shaped bacteria are called bacilli. Ball-shaped bacteria are called cocci. ________ bacteria are called _______.

Spiral-shaped, spirilla

_______ have bacteria in their stomach that absorb and break down ______. Cellulose is the compound that makes up wood, a termite's favorite food. The bacteria help the termite get energy and nutrients from wood.

Termites, cellulose

Many types of bacteria ________ from the material they________. Bacteria that break down dead organisms get their food in this way. You have bacteria in your digestive system that absorb nutrients from the food you eat.

absorb food, live on or in

Many types of bacteria do not have their own means of movement. Bacteria are simply carried by the movement of _____ . They can also be transferred from ______. For example, when you touch a surface, bacteria are transferred from that surface to your skin

air or liquid, surface to surface,

Bacteria in the soil take nitrogen out of the air and turn it into a form plants can use. When animals eat plants, they rearrange the ________ into other proteins. When an organism dies, bacteria break down the dead material and turn it back into ___ that living things can use again (Figure 7.10). Bacteria are "nature's recyclers."

amino acids, compounds

Bacteria are an important part of the nutrient cycles that all life depends upon. For example, plants need nitrogen to make ______, the building blocks of _____.

amino acids, protein

Have you ever had a bacterial infection? If so, you've experienced one of the harmful effects of bacteria. Bacteria cause diseases like strep throat, respiratory infections, and infected wounds. Bacterial diseases are treated with drugs called _______. Antibiotics kill _________ without harming your own cells. Different antibiotics are used for fighting different types of bacteria.

antibiotics, bacteria

There are many _______ in each environment. A square centimeter of your skin has thousands of bacteria. A teaspoon of soil contains more than a billion _______.

bacteria, bacteria

One species of _______ lives in your intestines. You provide the bacteria with a warm, safe place to live. In return, the bacteria help you break down and absorb certain compounds in ______. Bacteria even make some vitamins that your cells cannot make on their own.

bacteria, foods

Scientists believe that ________ were the first _________ on Earth. Evidence comes from fossils of single-celled prokaryotes found in rocks that are more than 3 billion years old.

bacteria, organisms

Some ______ cells exist as ______ while others exist in pairs, chains, or clusters. The graphic below shows the shapes of bacteria.

bacterial, individuals

Many types of bacteria absorb food from the material they live on or in. Bacteria that_______dead organisms get their food in this way. You have bacteria in your _______ that absorb nutrients from the food you eat.

break down, digestive system

Bacteria take elements like _______ and ______ out of the air and turn them into compounds living things can use. They recycle nutrients from dead plants and animals so they can be reused.

carbon, nitrogen

Bacterial cells have a _______that is surrounded by a tough ______ (Figure 7.6).

cell membrane, cell wall

Bacterial cells have a ______ membrane that is surrounded by a tough cell _______ (Figure 7.6).

cell, wall

Cyanobacteria are examples of photosynthetic bacteria (right). Bacteria that live around volcanic vents or other harsh environments can make their own food without sunlight. They use ______ to produce their food instead of energy from the sun. This process is called __________.

chemicals, chemosynthesis

Rod-shaped bacteria are called bacilli. Ball-shaped bacteria are called _____. ______bacteria are called spirilla.

cocci, Spiral-shaped

Bacteria are often described according to the shape of their cells. Rod-shaped bacteria are called bacilli. Ball-shaped bacteria are called ______. Spiral-shaped bacteria are called _______.

cocci, spirilla

Bacteria take elements like carbon and nitrogen out of the air and turn them into ________living things can use. They recycle _______ from dead plants and animals so they can be reused.

compounds, nutrients

Eventually, _____________ developed from __________. A scientific theory states that long ago, smaller prokaryotic cells were engulfed by larger prokaryotic cells. The smaller cells began to survive by living inside of the larger cells. Over time they took on specific functions inside the larger cells like producing energy. Eventually, the smaller cells became the organelles (like mitochondria) inside of eukaryotic cells (Figure 7.9).

eukaryotic cells, bacteria

Bacteria are and some can make you sick. But did you know that many types of bacteria are ______? In fact, life on Earth depends on them.

everywhere , helpful,

Bacteria move around in many ways. Some bacteria move using flagella. They rotate their ________ to___ themselves through liquid environments (Figure 7.8). Other bacteria have a slimy layer on the outside. They use it to slide over surfaces.

flagella, propel

Bacteria are an important part of the nutrient cycles that all ____ depends upon. For example, plants need _______ to make amino acids, the building blocks of protein.

life, nitrogen

Bacteria move around in _______. Some bacteria move using ____. They rotate their flagella to propel themselves through liquid environments (Figure 7.8). Other bacteria have a slimy layer on the outside. They use it to slide over surfaces.

many ways, flagella

Bacteria move around in ______ ways. Some bacteria move using _______. They rotate their flagella to propel themselves through liquid environments (Figure 7.8). Other bacteria have a slimy layer on the outside. They use it to slide over surfaces.

many, flagella

Bacteria live on or in just about every_______ and environment on Earth. They live in ____, water, and air. They are found in the coldest regions of the Arctic and even in boiling waters near undersea volcanoes.

material, soil

Many types of bacteria do not have their own _________. Bacteria are simply carried by the movement of air or liquid. They can also be _________ from surface to surface. For example, when you touch a surface, bacteria are transferred from that surface to your skin

means of movement, transferred

Many types of bacteria do not have their own means of ______. Bacteria are simply carried by the movement of __________. They can also be transferred from surface to surface. For example, when you touch a surface, bacteria are transferred from that surface to your skin

movement, air or liquid

Bacteria in the soil take _______ out of the air and turn it into a form ________ can use. When animals eat plants, they rearrange the amino acids into other proteins. When an organism dies, bacteria break down the dead material and turn it back into compounds that living things can use again (Figure 7.10). Bacteria are "nature's recyclers."

nitrogen, plants

One of the products of photosynthesis is ____. Over hundreds of millions of years, the amount of oxygen in Earth's atmosphere increased. This allowed ________ to develop. Aerobic bacteria use oxygen for cellular respiration. There are many different species of aerobic bacteria living today.

oxygen, aerobic bacteria

One of the products of photosynthesis is oxygen. Over hundreds of millions of years, the amount of _________ in Earth's atmosphere increased. This allowed _______ to develop. Aerobic bacteria use oxygen for cellular respiration. There are many different species of aerobic bacteria living today.

oxygen, aerobic bacteria

Anaerobic bacteria do not require ______for _____________. Today, anaerobic bacteria thrive in places that have little or no oxygen, like swamps.

oxygen, cellular respiration

Some bacterial cells exist as individuals while others exist in ______, ____, or clusters. The graphic below shows the shapes of bacteria.

pairs, chains

One of the products of _______ is oxygen. Over hundreds of millions of years, the amount of oxygen in Earth's atmosphere increased. This allowed aerobic bacteria to develop. Aerobic bacteria use oxygen for ________. There are many different species of aerobic bacteria living today.

photosynthesis, cellular respiration

Over time, some bacteria developed the ability to use _______. Cyanobacteria, still in existence today, were one of the first ________ bacteria.

photosynthesis, photosynthetic

Bacteria take elements like carbon and nitrogen out of the air and turn them into compounds living things can use. They recycle nutrients from dead _______ and _____ so they can be reused.

plants, animals

Scientists believe that bacteria were the first organisms on Earth. Evidence comes from fossils of single-celled ______________ found in rocks that are more than _________.

prokaryotes, 3 billion years old

Bacteria are the only _________ (cells with no nuclei). All other life forms on Earth are ________.

prokaryotes, eukaryotes

Eventually, eukaryotic cells developed from bacteria. A scientific theory states that long ago, smaller ____________ cells were engulfed by larger prokaryotic cells. The smaller cells began to survive by living inside of the larger cells. Over time they took on specific functions inside the larger cells like producing energy. Eventually, the smaller cells became the ________ (like mitochondria) inside of eukaryotic cells (Figure 7.9).

prokaryotic, organelles

Archaebacteria are found in extreme environments like volcanic vents in the ocean. They are thought to be the first organisms on Earth. Eubacteria are found almost everywhere else and have a different chemical makeup than archaebacteria. Both types of bacteria are ________, _____________. As future discoveries are made, these groups may change.

prokaryotic, single-celled organisms

Many kinds of bacteria have developed close _________ with other organisms. In many relationships the bacteria and the organism it lives with benefit. We learned in Chapter 3 that this type of symbiosis is called __________

relationships, mutualism

Bacteria move around in many ways. Some bacteria move using flagella. They _______their flagella to propel themselves through liquid environments (Figure 7.8). Other bacteria have a _______ on the outside. They use it to slide over surfaces.

rotate, slimy layer

Bacteria are often described according to the _______of their cells. Rod-shaped bacteria are called_______. Ball-shaped bacteria are called cocci. Spiral-shaped bacteria are called spirilla.

shape, bacilli

Bacteria move around in many ways. Some bacteria move using flagella. They rotate their flagella to propel themselves through liquid environments (Figure 7.8). Other bacteria have a _____ on the outside. They use it to _____ over surfaces.

slimy layer, slide

Bacteria get their food in many ways. Photosynthetic bacteria make their own food from ____ and _____, just like plants. Also like plants, they produce oxygen.

sunlight, carbon dioxide

_____ bacteria are called bacilli. ____bacteria are called cocci. Spiral-shaped bacteria are called spirilla.

Rod-shaped, Ball-shaped

The average bacterial cell is about 1.5 million times smaller than the average person. Bacteria are not easy to measure using meters, centimeters, or even millimeters. _________ (μm) are used to measure them. One micrometer is equal to_______of a meter. The size of bacteria range from 1μm to 5μm. Eukaryotic cells tend to be about ten times larger than bacterial cells (Figure 7.7).

Micrometers, one-millionth

Some scientists group all bacteria into the Kingdom _________. Others divide bacteria into two kingdoms, _______ and Eubacteria.

Monera, Archaebacteria

Bacteria get their food in many ways. _________ bacteria make their own food from sunlight and carbon dioxide, just like plants. Also like plants, they produce _______.

Photosynthetic, oxygen

Bacteria get their food in many ways. __________ bacteria make their own food from _______ and carbon dioxide, just like plants. Also like plants, they produce oxygen.

Photosynthetic, sunlight