Download Overview - Hadley School for the Blind

Overview
Science is very much a part of your everyday life.
Whether you consider the basic electrical bulb or
cutting-edge developments in agriculture and medicine,
you soon realize that science is all around you. This
course discusses the various areas of science, such as
life science, physical science, and earth science.
Examining scientific facts and developments will enable
you to explore the role that science plays in your life
and your environment.
The course components that enable you to achieve this
goal include the textbook Pacemaker's General Science
(3rd edition), published by Globe Fearon, and this study
guide. The study guide, developed by the staff and
faculty of The Hadley School for the Blind, guides you
through the course.
Study guides are popular tools for completing distance
education courses. This study guide introduces the
material presented in the textbook and offers specific
directions for completing each chapter. It provides
answers to select review exercises. It also presents
Enrichment Activities to replace the Lab Activities
featured in the textbook.
This course is divided into seven units. Unit 1
introduces some of the wonders and practical aspects
of science. Units 2 and 3 examine different facets of
life science. Units 4 and 5 focus on physical science.
Units 6 and 7 discuss earth science. Note that the
textbook features a Glossary and several appendixes,
all of which are optional material.
To complete each chapter, follow the instructions and
complete only the activities specified in the study
guidelines. As you complete the selected exercises,
keep the following in mind:
•
Note your answers in the medium of your choice
so you can compare them with those provided in
the study guide.
•
Do not send answers to review exercises to your
Hadley instructor.
•
If necessary, contact your instructor to clarify
concepts.
You are required to submit all the assignments
presented in the study guide. They enable your
instructor to evaluate your progress throughout the
course.
Chapter 4: Cells and Life
The previous chapter gave you some insight into the
study of life. You probably have questions about living
things themselves. How are they put together, and
how do they work? Chapter 4 studies the cell, which is
the basic unit of life, as explained in Lesson 4.1. It
relates how Robert Hooke discovered the cell, and it
compares cells to atoms, molecules, and elements.
Lesson 4.2 describes the parts of the cell and how they
work together. It contrasts plant and animal cells, and
it discusses DNA. Examining the relationship between
cells and life can help you explore the role that science
plays in your life and your environment.
Study Guidelines
To complete this chapter, use your textbook and do the
following:
1. Read pages 48 through 61.
2. Complete the lesson reviews on pages 52 and 57.
3. Skip the Lab Activity on page 58, as it is optional.
4. Complete the Vocabulary Review and Chapter Quiz
on pages 60 and 61. (Note that the Research
Project is optional.)
When you are finished, return to the study guide to do
the following:
5. Compare your answers.
6. Do the Enrichment Activity.
7. Complete the assignment.
Lesson Reviews
Answers for Page 52
1. Robert Hooke saw plant cells through his
microscope.
2. Molecules are made of atoms that are chemically
bonded to one another.
3. There are 112 different elements.
4. Water is not an element because it is made of
more than one kind of atom. A water molecule is
formed when two hydrogen atoms combine with
an oxygen atom.
Answers for Page 57
1. Animal and plant cells include the following cell
parts:
•
cytoplasm
•
cell membrane
•
nucleus
•
vacuole
•
mitochondria
2. Water and carbon dioxide are the byproducts of
cellular respiration.
3. Chlorophyll allows a plant to make its own food.
4. Police could prove that a strand of hair found at
the scene of a crime belongs to the suspect by
comparing the DNA in the hair from the crime
scene, to the DNA in the hair of the suspect.
Chapter 4 Review
Answers to Vocabulary Review (page 60)
1. True. Oxygen is an element because it is made of
only one kind of atom.
2. False. Food molecules pass into a cell through the
cell membrane.
3. False. A cell wall covers the cell membrane in
plants.
4. True. Cell parts that help the cell store and use
energy are called mitochondria.
5. False. Plants are green because they have
chlorophyll.
6. True. The nucleus controls all the other parts of a
cell.
7. False. Vacuoles float in the cytoplasm of a cell.
8. True. Chlorophyll is found in a chloroplast.
Answers to Chapter Quiz (page 61)
1. Robert Hooke discovered cells.
2. The Periodic Table of Elements is a list of all
elements.
3. Molecules are formed when atoms are joined by
chemical bonds.
4. The nucleus is called the cell’s “command post”
because it controls all the other parts of the cell.
5. Vacuoles store three things: food, water, and
waste.
6. Answers will vary. Reasons why cells need energy
may include three of the following:
•
to get and use food
•
to move
•
to grow
•
to reproduce
•
to respond
7. Food and oxygen are the two things that must
pass into a cell in order for the cell to get energy.
8. Plant cells are able to make their own food because
they have chlorophyll. Animal cells do not have
chlorophyll.
9. The structure of a DNA molecule looks like a
twisted ladder.
10. DNA determines a person’s eye color because the
DNA contains a code that controls eye color.
Enrichment Activity: Discovering Cells
Background
All cells have many of the same structures. Plant cells
are different from animal cells in a few important ways,
however.
Purpose
You will describe a plant cell and then an animal cell.
What To Do
1. Imagine that you are very, very small. Write a
paragraph about what it would be like to take a trip
through a plant cell. Describe what you observe as
you move around the part of the cell. Make sure
you accurately describe cell structures, and that
you include structures unique to plant cells.
2. Now imagine that you are taking a trip through an
animal cell. Write a paragraph about your journey.
Make sure that you accurately describe cell
structures.
3. As you complete your journeys, make sure you
consider the following questions:
•
What cell parts are you finding in both the
plant cell and the animal cell?
• What cell parts are in the plant cell but not in
the animal cell?
Draw Conclusions
Based on your imaginary journeys, what can you
conclude about plant cells and animal cells?
Answer: The cell membrane, cytoplasm, nucleus,
vacuoles, and mitochondria are cell parts found in both
plant cells and animal cells. The cell wall and
chloroplasts are found in plant cells but not in animal
cells. You would conclude that plant cells and animal
cells share some characteristics but are different in
some important ways.
If you found this material difficult, review the chapter.
Otherwise, proceed with the assignment that follows.
Assignment 4
For information on completing assignments, refer to the
instructions entitled “Getting Started.” Then begin this
assignment by giving your full name, address, and
phone number. Also list the name of this course,
Assignment 4, your instructor’s name, and the date. Be
sure to include the question number along with each
answer. This assignment is worth 100 points.
Vocabulary
Give the correct term for the following definitions.
(2 points each)
1. the smallest, most basic unit of life
2. matter that is made of only one kind of atom
3. two or more atoms that are joined by chemical
bonds
4. the watery substance in a cell
5. the thin covering that holds the cell together
6. the part of a cell that controls all the other parts
7. a part of the cell that stores food, water molecules,
and waste
8. the process cells use to release energy from food
molecules
9. a green material in plants that allows plants to
make their own food
10. a molecule that controls the characteristics of
living things
Multiple Choice
Answer the following questions by choosing the
correct answer. (3 points each)
11. Which of the following statements is true about
microscopes?
a. They make things look much smaller than they
really are.
b. They are used for observing distant stars.
c. They make things look much bigger than they
really are.
12. How did Robert Hooke discover cells?
a. by looking at tree bark under a microscope
b. by splitting the atom
c. by combining oxygen and hydrogen
13. What is a chemical bond?
a. a force that holds atoms together
b. part of a microscope
c. the thin covering that holds a cell together
14. Which of the following statements is true?
a. Cells are found only in plants.
b. Every living thing has at least two cells.
c. Cells are the building blocks of life.
15. Where in the cell are food molecules broken down?
a. the mitochondria
b. the nucleus
c. the vacuole
16. Which part of the plant cell stores chlorophyll?
a. a mitochondrion
b. a cell wall
c.
a chloroplast
17. Why can a tree make its own food?
a.
b.
c.
Each leaf cell contains cytoplasm.
Each leaf cell has a nucleus.
Each leaf cell has chloroplasts.
18. Which of the following statements is true?
a. Plant and animal cells are identical.
b. A plant cell has some structures that an animal
cell does not have.
c. An animal cell has some structures that a plant
cell does not have.
19. Which of the following statements is true about
DNA?
a. It controls many of the characteristics of living
things.
b. It is one of the shortest molecules found in
living things.
c. Organisms in the same species all have
identical DNA.
20. Which of the following statements about cancer
cells is true?
a. They appear identical to healthy cells when
looked at with a microscope.
b. They reproduce quickly and can crowd out and
kill a person’s healthy cells.
c.
Doctors offer no treatment because eventually
the cells will stop reproducing.
Short Answer
Respond to the following questions with brief,
complete answers.
21. Imagine an animal cell as a city. Consider the parts
of a city: the land on which it is built, the city’s
border, and government offices or a city hall. Other
components are the various stores, gas stations,
and places of business, and the people who live
and work in the city. Compare five parts of the
animal cell to five similar city parts. (20 points)
22. You are a reporter following a criminal case where
DNA may play a key role in helping to convict a
suspect. As your newspaper article needs to
include a brief explanation of what DNA is, prepare
a draft of your text by answering the following
questions:
a. What is DNA and where is it found? (9 points)
b. How does DNA control the characteristics of
living things? (9 points)
c.
Give three examples of DNA-controlled human
characteristics that might help support witness
testimonies. (12 points)