B.1.2_Cells and Organisms

Reading 1Science Cells and Organisms ✓ Find the Main Idea and Details What is the topic of this chapter?. 4 3 1 Lung cell 2 Lung tissue Lung Trachea Respiratory system Word Study Word

Reading 1

Science

Cells and Organisms

✓

Find the Main Idea and Details What

is the topic of this chapter? How are the pictures related to this

topic ?

Reading Strategy

5

2

8 3

4

6 7

9

12

11 10

1

A (plant) cell

FOCUS QUESTION

What one part do all cells have?

The Cell

1 cell

2 cytoplasm

3 cell membrane

4 chloroplast

5 vacuole

6 nucleus

7 endoplasmic reticulum

8 ribosome

9 Golgi complex

10 lysosome

11 mitochondria

12 cell wall

Word Study

Multiple-Meaning Words

The word cell has different meanings.

Acell is “a small room

locked from the outside.”

People in jail are kept

incells.

Acell is the “basic unit of

living things.”

Your body is made up

of many cells.

Find the Main Idea

details on this

textbook page seem

important to you?

How do you know

they are important?

Reading

Strategy

boxed item

6 2

10

3

5

7

9

8

1

An (animal) cell

11

Check Your Understanding

1 Look at the plant cell and animal cell

Name five parts that both cells have

2 What does the nucleus do?

3 What one part do all cells have?

Critical Thinking Making Inferences

4 Why do cells have many different parts?

Vocabulary in Context

All living things are made up of one or morecells.

Cells are the smallest unit of life All cells have a cell

membrane It controls what moves into and out of a

cell Most cells have other parts, such as a nucleus,

vacuoles, ribosomes, and lysosomes The nucleus

controls all activity in the cell Vacuoles store water,

food, and waste Ribosomes build proteins Lysosomes

break down, or digest, material

1 Use text elements

What are two meanings of the

word cell? Where

did you find the

illustration caption

Find the Main Idea and Details What is the main idea of this paragraph? Identify

two details that support this idea.

Reading Strategy

4 3

1

Lung cell

2

Lung tissue

Lung Trachea

Respiratory system

Word Study

Word Parts

Multicellular is made up of two word parts.

The prefix multi can mean “much” or “many.”

The word cellular can mean “made of cells.”

Amulticellular animal is made up of many cells.

1 cell

2 tissue

3 organ

4 organ system

Multicellular Organisms

FOCUS QUESTION

What is a multicellular organism?

chapter title

Find the Main Idea

and Details What

details in the diagram

support the main idea

of this page?

Reading

Strategy

3

Flowers

1

Leaf cell

2

Leaf tissue

Stem

4 systemShoot

Vocabulary in Context Trees, people, and many other living things are made

up of many cells They are multicellular organisms

Groups of the same kind of cell form tissues All the cells

in a tissue do the same kind of work For example, lung tissue helps you breathe Tubes in plant stems carry things between the roots and leaves Those tubes are a tissue

Two or more different tissues that work together form

anorgan A lung is an animal organ A leaf is a plant

organ Several organs that work together form organ systems For example, your lungs form part of your

respiratory system The leaves, stems, and flowers on

a plant are in the plant’s shoot system

Check Your Understanding

1 Look at the pictures What are tissues made of?

2 Give two examples of organs Give two examples

of organ systems

3 What is a multicellular organism?

Critical Thinking Comparing and Contrasting

4 How are tissues different from organs?

1 Define Answer

question 3 in the “Check Your Understanding” box.

2 Use text elements

Find the Main Idea

the main idea of this text? What is the main idea of the diagram? How do the text and the diagram help you to understand the main idea of the page?

Reading Strategy

Multicellular Organisms

Looking for Details

A table presents information in rows and columns Sometimes a table will present details Details are small, important pieces of information

1 Which two cells help protect the body? Which two cells help the body move?

2 What are three jobs that muscle cells have in the body?

3 Which cell causes the heart to beat?

Science Skill

Kinds of Animal Cells

Multicellular animals contain many different kinds of cells Each kind of cell has a certain job No other kind of cell can do that job For example, red blood cells collect gases in the lungs White blood cells protect the body against disease They cannot collect gases in the lungs

Animal Cells and Their Jobs

Kind of Cell What does this kind of cell do?

cardiac muscle cell The heart is made up of cardiac muscle cells This kind of cell causes the heart to beat

skeletal muscle cell Skeletal muscle cells are connected to bones This kind of cell forms tissues that help move bones

smooth muscle cell This kind of cell forms organs that help move food in the digestive system It also lines blood vessels and the airways of the lungs

bone cell The skeleton is made up of bone cells This kind of cell provides support and allows the body to move.

skin cell This kind of cell and germs. protects the outside of the body from injury

red blood cell This kind of cell carries gases to other cells in the body.

white blood cell This kind of cell fights disease in the body White blood cells hunt and eat germs and bacteria

bold term

section

table

Find the Main Idea

the “Science Skill”

questions about

details in the table

Based on your

answers, what is

the main idea of this

page?

Reading

Strategy

How Cells Divide

Cell division is the way an organism makes new cells or

repairs an injury

First, the cell copies its chromosomes Chromosomes are in

the cell’s nucleus Chromosomes have information on how to

make new cells Next, the two sets of chromosomes move away

from each other Finally, the cell separates into two new cells

Each new cell gets one set of chromosomes








Cell Division

Word Study

Phrasal Verbs

Phrasal verbs are made up of two or three words

Move away from means “to go to a different place.”

Two sets of chromosomes move away from each

other when a cell divides

Check Your Understanding

1 How do red blood cells help the body?

2 How do bone cells help the body?

3 What are three important steps in cell division?

Critical Thinking Applying Information

4 You get a small cut What do cells do to help your skin heal?

Research and Inquiry Use the internet, the library, or your

science book to answer these questions

1 Why is the skin an organ system?

2 Why is an artiflcial heart not an organ?

3 How do skeletal muscles make bones move?

WritingSuppose you fall and scrape your knee

How do your white blood cells help you heal? Write

a paragraph

1 Recall details Answer question 1

in the “Check Your Understanding”

Find the Main Idea

is the main idea

of this entire text?

What information on this page helps you understand the main idea better?

Reading Strategy

questions

Find the Main Idea

is the main idea

of this entire text?

What information on this page helps you understand... Information

4 You get a small cut What cells to help your skin heal?

Research and Inquiry Use the internet, the library, or your

science book to answer these questions... an organ?

3 How skeletal muscles make bones move?

WritingSuppose you fall and scrape your knee

How your white blood cells help you heal? Write

a paragraph

1