Download Slides of plant and animal cells

Biology Cell Unit Homework Packet #2
Name
DUE:
HW #2
Cell Size
Lab
HW #3
Cell Parts
Reading
Questions
HW #4
Create Your
Own Cell
Analogy
Hour
Hypothesis
Data Table
Graph
Questions
____
____
____
____
Accuracy
____
Completion
Accuracy
____
____
_______ / 5 possible points
Homework #2: Cell Size Lab
(from Biology: Living Systems, pg. 120-121)
Introduction: In this lab, you will determine the size of plant and animal cells. Your
teacher will supply a millimeter ruler and a variety of plant and animal cells. You can
measure the diameter of the field of view under low power with your millimeter
ruler. It will be easier for you to make your measurements in millimeters. However,
because cells are very small, convert your answers to micrometers. There are 1000
micrometers (m) in 1 millimeter (mm). (For example, 1.8 mm is equal to 1800 µm).
Problem: How big are cells?
Materials:
Microscope
Ruler
Slides of plant and animal cells
Calculator
Methods:
1. Take out your microscope and properly set it up as we did in the
Microscope Lab.
2. Set your microscope to LOW power.
3. Record the Eyepiece and Objective magnification in Table 1.
4. Mathematically, determine the Overall magnification.
5. Use your ruler to measure the diameter of the field of view in
millimeters. Record your answer in Table 1.
6. Convert the diameter in millimeters to micrometers. Record your
answer in Table 1.
7. Repeat steps 2 and 3 for MEDIUM and HIGH power.
8. Obtain a slide and estimate the number of cells across the field of
view as in Figure 1. Record your answer in Table 2.
1
2
3
45 6
7 8 9 10
9. Individual cell size can be determined using the following equation:
(Field of view diameter) ÷ (# of cells)
Use your math skills to determine the estimated cells of each
individual cell in micrometers. Record your answers in Table 2.
Data and Observations:
TABLE 1. Measuring the field of view
Setting
Ex. Super Low
LOW
Eyepiece
magnification
Objective
magnification
Overall
magnification
10x
2x
20
10x
4x
10x
10x
40x
MEDIUM
HIGH
100x
4x
10x
40x
400x
Field of
View
Diameter
(mm)
10 mm
Field of
View
Diameter
(m)
5,000
TABLE 2. Estimating the size of cells
Cell Type
EXAMPLE:
Mosquito wing
Microscope
Setting
Super Low
Frog Blood
High
Testes
High
Corn Stem
Medium
Onion Root
High
# of cells
Estimated Cell
Size (m)
10
Analysis and Conclusions:
-
Prepare a bar graph that shows the relationship of cell type (X-axis) to cell
size (Y-axis). Be sure to include a title, key, and labeled axis (X and Y) on your
graph. DO NOT INCLUDE THE MOSQUITO WING! Neatness counts.
Post-Lab Questions:
Answer the following questions using complete sentences (neatness counts!). I will
be really impressed if you use what you know about cells and cell parts to answer
them.
1. Which specific cell type was smallest? Speculate about why it is an advantage
for that type of cell to be so small.
 Testes (sperm cells)
 Sperm cells are so small due to the function of the cell.
Their job is to fertilize eggs and they have only what is
necessary to accomplish this task: little cytoplasm, many
mitochondria for energy, and 23 chromosomes to pass on
genetic information.
2. Which specific cell type was largest? Speculate about why it is an advantage
for the cell of that type to be large.
 Corn stem cells
 Corn stem cells are large due to the function that they
perform. Their jobs include: transport of water and sugars,
structural support of plant, etc.
3. Why do you think cells are different sizes?
 Cells are different sizes and shapes due to the functions that
they perform.
Homework #3: Chapter 5 Reading Questions
(please use complete sentences)
1. One of the parts of the cell theory states that “all living things are made of
cells”. Give three examples of things that would not be made of cells.
A.
B. Answers will vary. Anything made out of metal, plastic, etc.
C.
2. Cells of the eye (page 723) are shaped like rods and cones. White blood cells
(page 604) are shaped like bumpy round balls. Plant cells (page 583) tend to be
more rectangular than animal cells. Why are cells of many different shapes and
sizes?




Rod Cells: most sensitive; permit vision in dim light
Cone Cells: distinguish color; sharpen image
White Blood Cells: protect against foreign invaders
Plant Cells: support; shape
The function of the cells determines the shape of the cells.
3. Complete the chart below with either the name or function of the appropriate
cell structure.
Structure
Function
Mitochondria
Creates energy for the cell
Ribosome
Important in the creation of proteins
Chromosomes
Contains the hereditary information
Vacuole
Storage of water, undigested food, and or wastes
Nuclear
Semi-permeable membrane surrounding nucleus
Membrane
Lysosome
Storage of digestive enzymes
Chloroplasts
Contains chlorophyll to attract sunlight energy
Golgi Body
4. Fill in the following Venn Diagram to compare and contrast animal and plant
cells. Which cell parts do they have in common? Which cell parts are unique?
JUST ANIMAL
CELLS
BOTH
Cell membrane
Mitochondria
Nucleus
Chromosomes
JUST PLANT
CELLS
Chloroplasts
Cell wall
Large vacuoles
ER
Golgi body
Ribosomes
5. Predict which organ in your body is composed of cells that contain the greatest
number of mitochondria. Explain your answer.

Answers will vary. Any cells that require a great amount of
energy will have many mitochondria.
6. In class we learned that plants have large vacuoles. Why would plant cells have
larger vacuoles than animal cells?
 Vacuoles are used for storage. Because vacuoles store liquid,
they help to keep cells stiff. Storage of water also allows
cell to get big without using much energy (cytoplasm is
metabolically costly).
Homework #4: CREATE YOUR OWN CELL ANALOGY
Over the past few days, you have been learning about cells and comparing them to a factory.
To help you get ready for tomorrow’s quiz, I would like you to develop a different comparison.
What else is a cell like? How would those parts fit into that analogy?
Work with your partner to develop your own analogy using the chart below. You must be able to
use at least 10 of the cell parts that we described in class. In the first column, write the name of
a cell part. In the second column, write the job the cell part would have in your analogy. In the
third column, give your rationale or reason why that particular cell part would do that job in your
analogy.
A cell is like a Answers will vary.
Cell Part
Job
Rationale