Unit 1: Characteristics of Life (3)

What is the basic unit of life?

The cell.

What are the three main characteristics of living things?

Made of cells, need energy, and respond to stimuli.

What is a stimulus?

Anything that causes a response

What is the plural of stimulus?

Stimuli

Why do living things need energy?

To carry out life functions and survive.

What does it mean to respond to stimuli?

To react to changes in the environment.

What are life functions?

Processes that help an organism survive.

How many life functions are there?

Eight.

Name the eight life functions.

Growth, reproduction, nutrition, respiration, transport, synthesis, excretion, and regulation.

What is growth?

An increase in the number of cells.

Why are adults larger than babies?

Adults have more cells.

Growth is an increase in the number of what?

Cells.

How does growth help organisms?

It helps them survive better in their environment.

What is reproduction?

The creation of a new organism with its own cells.

What is the result of reproduction?

Offspring.

What is an offspring?

A new organism produced by reproduction.

What is asexual reproduction?

Reproduction involving one parent.

What is sexual reproduction?

Reproduction involving two parents.

How many parents are involved in asexual reproduction?

One

How many parents are involved in sexual reproduction?

Two

What type of reproduction do bacteria usually undergo?

Asexual reproduction.

What is nutrition?

The taking in of food (nutrients).

What are nutrients?

Substances that promote life and provide energy.

Why are nutrients important?

They promote life and provide energy.

What is an autotroph?

An organism that makes its own food.

Give an example of an autotroph.

Plants.

What is a heterotroph?

An organism that cannot make its own food.

Give an example of a heterotroph.

Animals.

What does the prefix "auto-" mean?

Self.

What does the prefix "hetero-" mean?

Other.

What does "-troph" mean?

One who is nourished.

How do autotrophs obtain nutrients?

They make their own food.

How do heterotrophs obtain nutrients?

By consuming other organisms.

What is respiration?

The breakdown of nutrients to obtain energy.

What is metabolism?

The set of chemical reactions that maintain life.

What begins after nutrients are ingested?

Metabolism.

What is digestion?

The breakdown of nutrients into simpler forms.

Why does digestion occur?

To make nutrients easier for the organism to use.

What is cellular respiration?

A process that uses glucose and oxygen to produce energy.

Which two substances are used in cellular respiration?

Glucose and oxygen.

What is produced during cellular respiration?

Energy

What is transport?

The movement of materials throughout an organism.

What is circulation?

The movement of something through the body of an organism.

What happens to nutrients after digestion?

They are transported throughout the body.

In humans, transport moves nutrients from where to where?

From the stomach to the cells.

What is synthesis?

Using energy to build more complex chemicals.

Give two examples of substances made during synthesis.

Carbohydrates and proteins.

Does synthesis build simple or complex chemicals?

Complex chemicals.

What is excretion?

The removal of waste from the body.

What is a waste product?

A substance that is no longer useful to the body.

Give an example of a substance that is both ingested and excreted.

Water

How can water be excreted?

As sweat

When a substance is not useful to the body, it is what?

Excreted.

What is regulation?

Adjusting internal conditions to survive changing environments.

Why is regulation important?

It helps organisms survive environmental changes.

What is homeostasis?

A stable internal environment.

Define homeostasis.

A state of steady physical and chemical conditions within the body.

What is the purpose of homeostasis?

To maintain stable internal conditions.

What does homeostasis keep stable?

The body's internal environment.

What does the word "homeo" mean?

Same.

What does the word "stasis" mean?

State.

What does homeostasis literally mean?

Same state.

How does homeostasis help organisms survive?

It keeps internal conditions stable despite external changes.

What is adaptation?

A behavior or physical characteristic that helps an organism survive or reproduce.

How does adaptation affect survival?

It can improve an organism's ability to survive and reproduce.

Can adaptations be behavioral or physical?

Yes.

Give an example of an adaptation.

Camels surviving long periods without water.

How long can camels survive without drinking water according to the notes?

About six or seven months.

Why are camels able to live in deserts?

They have adaptations that help them survive there.

What are three characteristics of all living things?

Made of cells, need energy, respond to stimuli.

What are life functions?

Processes that help organisms survive.

Growth is an increase in the number of what?

Cells.

What is the outcome of reproduction?

A new organism (offspring).

What form of reproduction do bacteria usually undergo?

Asexual reproduction.

Why are nutrients important?

They promote life and provide energy.

What are the two ways nutrients can be obtained?

Created by the organism or ingested.

What happens to substances that are not useful to the body?

They are excreted.

What is the purpose of homeostasis?

To maintain a stable internal environment.

How can adaptation affect survival?

It can help or hinder an organism's ability to survive.