1. Introduction

Biology: it’s the study of (-ology) life (bio-).

So what is life? How do we know when something is alive?

Let’s look at the key properties shared by living things. As we proceed, the following definitions will be useful. Read them over before starting.

  • Energy: the ability to do work. Energy can be chemical (food, gasoline), radiant (like light), or mechanical
  • Species: a group of similar organisms that can successfully interbreed.
  • Homeostasis: adjusting to the environment in a way that maintains constant internal conditions
  • Evolution: change over time
  • Adaptation: traits that promote survival and/or reproduction.

2. Interactive Reading: The Eight Properties of Living Things

[qwiz qrecord_id=”sciencemusicvideosMeister1961-Properties of Life (IR)M1″]

[h]Interactive Reading: Properties of Life

[i] All life, made of cells

Organized and adapted

through evolution

  • If you’re at school, sharing a computer, follow all the guidelines for good partner work: Share the work, listen; lean in (with the computer positioned in between the two of you; and use a low voice).

 

[q labels = “top”]

Trait 1. Living things are made of cells

01_Hooke_Micrographia_cork_1280 copy
Cork (bark) cells, drawn by Robert Hooke. The cells are magnified about 100x (source: wikipedia commons)

In every living thing that’s ever been known to exist, you’ll find that the organism is built of tiny units called _______. Cells are the basic units of life.

The drawing at left, drawn using an early microscope in the 1600s, shows tiny cells (each square is a cell).

02_elodea
A cell from a photosynthetic plant, magnified about 400x. (source: www.micrographia.com)

On the right, you can see a rectangular cell from an aquatic (water-living) plant. The small green ellipses are parts that carry out _______________. .

Plants, animals, and fungi are made of many cells. But bacteria, yeast, and most algae consist of just _____ cell. In fact, for the first few billions of years of life on Earth, that’s all that life was: ________________ organisms.

[l]single‑celled

[fx] No. Please try again.

[f*] Excellent!

[l]photosynthesis

[fx] No. Please try again.

[f*] Excellent!

[l]one

[fx] No. Please try again.

[f*] Great!

[l]cells

[fx] No. Please try again.

[f*] Correct!

[q labels = “top”]

Trait 2: Living things are highly organized.

Organization of molecules in cell membranes. Magnified more than 20,000 times. Source, Wikipedia, created by LadyofHats)
Organization of molecules in cell membranes.
Organization in a geranium leaf. Magnified 0.25 X. Source, Wikipedia, by Sigman)
Organization in a geranium leaf. Magnified 0.25 X. Source, Wikipedia, by Sigman)

This means that living things, and their parts, are arranged and _________. Living things have lots of _____________ structure. They’re not randomly arranged. At any level that you look at life, from the entire organism, to specific parts of organisms, all the way down to the cells and molecules that make up organisms, you see high levels of ____________.

[l]ordered

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[l]organization

[fx] No, that’s not correct. Please try again.

[f*] Excellent!

[l]predictable

[fx] No, that’s not correct. Please try again.

[f*] Great!

[q labels = “top”]

Trait 3: Living things are maintained by a constant flow of energy and matter.

Flows of matter and energy: food and oxygen flow in. wastes flow out.

Every day (if you’re lucky), you eat food. That food contains chemical _______ that keeps you alive. It also provides you with the atoms that make you up. With every breath, oxygen flows into you. That flow can’t stop for more than a few minutes, or life will end.

Energy and matter flow through a plant (source: Wikipedia commons)

These flows of _________ and energy into you are matched by flows of matter and energy out of you. When you exhale, you breathe out carbon dioxide. Urine removes waste products from your blood. Feces removes food you can’t digest. You’re also releasing heat into the environment.

 

Like you, plants are also open systems, with matter and energy flowing through them. As a plant performs photosynthesis, carbon dioxide and water are flowing into it. Using _________ energy from the sun, the plant makes sugars and other carbohydrates. Oxygen is released as a waste product.

 

[l]energy

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[l]light

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[l]matter

[fx] No. Please try again.

[f*] Great!

[q labels = “top”]

Trait 4: Living things respond to their environment

06-stimulus-response-hot-234x300
Response to a stimulus (source: MeredithBond.com)
A plant bending towards the light (source: wikipedia, "Arabidopsis thaliana" by Brona)
A plant bending towards the light (source: wikipedia, “Arabidopsis thaliana” by Brona)

Humans, like all animals, constantly _________ to the environment. These responses might be quick ________, as is shown on the left when you touch a hot piece of metal. But these responses can also occur much more slowly. Even plants respond to their environments. That’s what happens when a vine wraps itself around a branch, or when a ________ grows so that its leaves face toward the sunlight.

[l]plant

[fx] No. Please try again.

[f*] Correct!

[l]reflexes

[fx] No, that’s not correct. Please try again.

[f*] Great!

[l]respond

[fx] No. Please try again.

[f*] Correct!

[q labels = “top”]

Trait 5: Living things maintain stable, internal environments through homeostasis

Humans can live in almost every environment imaginable, from the Saharan desert to the Alaskan tundra. But to stay alive, the conditions _________ our bodies must stay within a very narrow _________. Our body temperature has to stay very close to 37°C (98.6°F).  Levels of sugar and salt in the blood also have to be tightly regulated.

This process of regulation is called __________. If you get too hot, you sweat. As the sweat evaporates, your body cools down. Your temperature stays right around 37°C. If your blood becomes too acidic, your kidneys adjust the blood, moving it back to the _________ level.

[l]homeostasis

[fx] No, that’s not correct. Please try again.

[f*] Excellent!

[l]inside

[fx] No, that’s not correct. Please try again.

[f*] Good!

[l]range

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[l]right

[fx] No, that’s not correct. Please try again.

[f*] Excellent!

[q labels = “top”]

Trait 6: Living things reproduce by passing on their DNA

DNA (source, wikimedia commons)

While not every living thing __________, every living thing is part of a species in which members of that species pass their genes on to the next __________. In every living thing on Earth, those genes are encoded in a chemical called _______. If it has DNA, and can reproduce itself, it’s almost certainly alive.

 

 

 

 

[l]DNA

[fx] No, that’s not correct. Please try again.

[f*] Great!

[l]generation

[fx] No, that’s not correct. Please try again.

[f*] Excellent!

[l]reproduces

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[q labels = “top”]

Trait 7: Living things grow and develop

Human embryo, 6 weeks (source: Wikipedia commons)

Growing means increasing in size. Developing means changing form over the course of life.

In living things that consist of only one cell, most of what you see over the course of life is ______. A small cell grows to become a full-sized adult cell, which then divides again.

In living things like human beings that consist of trillions of cells, life begins as a single, fertilized ______, which then grows and develops into embryo, and then into a vastly ________, adult organism.

[l]egg

[fx] No. Please try again.

[f*] Good!

[l]growth

[fx] No. Please try again.

[f*] Great!

[l]larger

[fx] No. Please try again.

[f*] Good!

Trait 8: Every living things is a member of an evolving species.

The thorns on this cactus are an example of an adaptation (the cactus evolved thorns to keep away plant predators) (source: wikipedia)

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Through evolution, species _______ over time.

A species is a group of organisms that can naturally interbreed with one another to successfully reproduce. All humans are part of the same species. Grizzly bears and polar bears are two different species, because they don’t naturally interbreed with one another.

A species is adapted to its environment. That means that the species has traits that enable it to ________ and reproduce. Some obvious adaptations are:

  • The spines of a cactus which discourage animals from eating it
  • The talons of an eagle which enable it to grasp its prey

The process by which species become ________ to their environments is called natural _________. It’s one of the most important ideas in biology, and we’ll investigate it later in this course.

[l]adapted

[fx] No. Please try again.

[f*] Good!

[l]change

[fx] No, that’s not correct. Please try again.

[f*] Great!

[l]selection

[fx] No, that’s not correct. Please try again.

[f*] Good!

[l]survive

[fx] No. Please try again.

[f*] Good!

[x]

[restart]

[/qwiz]

3. Flashcards: Eight Properties of Living Things

These flashcards will help you master the vocabulary associated with the properties of living things.

[qdeck style=”width: 528px; border: 2px solid black; ” qrecord_id=”sciencemusicvideosMeister1961-Properties of Living Things Flashcards (M1)”]

[h] Flashcards: Properties of Living Things

[i] Here’s how these flashcards work.

  • Click ‘Flip’ to see the answer to each card.
  • If you know it, click ‘Got it.”
  • BE REALLY STRICT WITH YOURSELF! If you don’t know the term, click ‘Need more practice,’ and that card will go to the bottom of the deck so you can practice it again.
  • ‘Shuffle’ lets you shuffle the deck.

[!] CARD 1+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q] All living things are composed of one or more _________
[textentry]
[a] All living things are composed of one or more cells.

[!] CARD 2+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q] Living things are the opposite of random. Another way of saying that is that living things are highly  _________
[textentry]
[a]Living things are highly organized.

[!] CARD 3+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q] Animals have to take in food and oxygen. Plants have to take in light and carbon dioxide. This is because living things require constant flows of ______________________.
[textentry]
[a]Living things require constant flows of matter and energy.

[!] CARD 4+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q] You hear an unexpected sound, and you jump. This is an example of the fact that living things  ________________ to their environments.
[textentry]
[a]Living things respond to their environments, It’s fine if you wrote “respond to stimuli.”

[!] CARD 5+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q] You get cold. You shiver, and your body temperature rises. This is an example of the fact that living things work to maintain a constant _____________ environment.
[textentry]
[a]Living things work to maintain a constant internal environment.

[!] CARD 6+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]The process of maintaining a constant internal environment is known as _______________
[textentry]
[a]he process of maintaining a constant internal environment is known as homeostasis

[!] CARD 7+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]Dogs have puppies. Plants produce seeds. This is an example of the fact that living things are parts of a species that __________________.
[textentry]
[a]Living things are parts of a species that reproduces.

[!] CARD 8+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]When living things reproduce, they pass on their _____________
[textentry]
[a]When living things reproduce, they pass on their DNA. (It’s fine if you wrote “genes” instead)

[!] CARD 9+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]When a blue whale is born, it weighs three tons (2.7 metric tons). During its first year, it gains 200 pounds (91 kg) each day. What property of life is this an example of?
[textentry]
[a]This increase in size of blue whales is an example of the property of growth.

[!] CARD 10+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]As a seed grows, new structures like leaves, roots, and stems emerge. This is an example of ________________
[textentry]
[a]The emergence of new structures (like leaves, roots, and stems) during the course of life is an example of development.

[!] CARD 11+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]The change in the features and adaptations of a species that occurs over time (lots of time) is called ________________.
[textentry]
[a]The change in a features and adaptations of a species that occurs over time (lots of time) is called evolution.

[!] CARD 12+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++[/!]

[q]A feature that enables a species to survive in its environment is called a(n)________________.
[textentry]
[a]A feature that enables a species to survive in its environment is called an adaptation.

[x]

If you want more practice, please press the restart button below. Otherwise, follow the links below.
[restart]
[/qdeck]

4. Matching: Properties of Living Things

[qwiz qrecord_id=”sciencemusicvideosMeister1961-Properties of Living Things Matching (M1)”]

[h]Properties of Living Things Matching Quiz
[i]

[q]Drag the property of living things from the list on the right to the description that best matches that property. Be sure to choose the property that fits best.

  1. A bear smells berries and moves towards the smell.
    _______________________________________
  2. When it’s cold, you shiver, increasing your body temperature:
    _______________________________________
  3. You start life as a fertilized egg. Then you’re a ball of cells. Then a backbone and limbs appear.
    _______________________________________
  4. Plants need sunlight to perform photosynthesis:
    _______________________________________
  5. If you went back in time 100,000 years, the humans you would meet would not be the same as the people who exist today.
    _______________________________________
  6. Insect bodies are in three segments:
    _______________________________________
  7. Humans produce sperm and egg:
    _______________________________________
  8. Looking through a microscope at plant tissue, you see small repeated, rectangular units.
    _______________________________________

[l]Highly organized

[fx] No, that’s not correct.  Please try again.

[f*] Excellent!

[l]Made of cells

[fx] No.  Please try again.

[f*] Good!

[l]Open to matter and energy

[fx] No, that’s not correct.  Please try again.

[f*] Excellent!

[l]Response to environment

[fx] No.  Please try again.

[f*] Correct!

[l]Homeostasis

[fx] No, that’s not correct.  Please try again.

[f*] Good!

[l]Reproduction

[fx] No, that’s not correct.  Please try again.

[f*] Good!

[l]Growth and development

[fx] No, that’s not correct.  Please try again.

[f*] Correct!

[l]Part of an evolving species

[fx] No.  Please try again.

[f*] Correct!

 

[q]Drag the property of living things from the list on the right to the description that best matches that property. Be sure to chose the property that fits best.

  1. A mouse hides when it sees a cat.
    _____________________________________
  2. A spider eats a fly.
    _____________________________________
  3. Male blue whales mate with female blue whales
    _____________________________________
  4. 8 million years ago, one species of fruit fly arrived on the Hawaiian islands. Since then, that one species of fruit fly has repeatedly split and produced new species.
    _____________________________________
  5. Plants start from seeds. Soon, the seedling has a root, a stem, and leaves.
    _____________________________________
  6. Different plants have predictable patterns of veins on their leaves.
    _____________________________________
  7. Under a microscope, the tissue lining your inner cheek can be seen to be made of repeated, tiny units.
    _____________________________________
  8. Your blood sugar goes down. Your pancreas releases a hormone that gets muscle cells to release sugar into your blood.
    _____________________________________

[l]Highly organized

[fx] No, that’s not correct.  Please try again.

[f*] Good!

[l]Made of cells

[fx] No.  Please try again.

[f*] Great!

[l]Open to matter and energy

[fx] No, that’s not correct.  Please try again.

[f*] Correct!

[l]Response to the environment

[fx] No, that’s not correct.  Please try again.

[f*] Good!

[l]Homeostasis

[fx] No, that’s not correct.  Please try again.

[f*] Correct!

[l]Reproduction

[fx] No.  Please try again.

[f*] Great!

[l]Growth and development

[fx] No, that’s not correct.  Please try again.

[f*] Great!

[l]Part of an evolving species

[fx] No, that’s not correct.  Please try again.

[f*] Excellent!

[x]

[restart]

[/qwiz]

5. Next steps

If you need more practice, please scroll up to the top and work through this tutorial again. Otherwise, follow the links below: