Transcript Cells

9/6 Bell Work
4x4+4x4+4–4x4=?
78% of people get this wrong!
9/6 Schedule
• Is It Alive?
• Notes Ch 7.1 “Intro to Cells”
• Work Time
• DR 3.2 “Water” and “Chemistry” LATE
• Organic Molecules Notes Chart
• DR Ch 7 “Cells”?
Assignments:
1. Dir Rdg “Water” and “Chemistry” – LATE
2. Molecules Note Chart and Menu - TODAY
Unit Pt 2 : Cells
Ch 7 Objectives:
1. Describe cell structures and their functions.
2. Classify cells as prokaryotic or eukaryotic.
It’s Alive….?!?
• How do you know if something is alive?
• Think of 2-3 ideas in case someone takes yours!
Characteristics of Life
Things must show the following things to be considered alive:
• Grow
• Reproduce and pass on traits to offspring (heredity)
• Respond
• Metabolism (reactions for energy)
• Maintain stable internal conditions
• Made of cells
Data fails the test…
“Introduction to Cells”
(Ch 7.1)
Objectives:
1. Describe how cells were discovered.
2. Explain why cell size and shape vary.
3. Compare/contrast bacteria and other cells.
The Discovery of Cells
Improvements in making lens = better microscopes.
• Cells first discovered in the 1600s
• 1665: Robert Hooke looks at cork and sees “cells”
• 1675: Anton van Leeuwenhook discovers “animalcules” in pond
water.
Hooke sees empty spaces in
cork.
“Animalcules”
The Discovery of Cells
More powerful microscopes by the 1800s led to the cell
theory.
Parts
1. All living things have one or more cells.
2. Cells are the basic unit of structure and function.
3.
Cells come from other cells.
Looking at Cells
Cells vary greatly in their size and shape.
Shape reflects function.
• branched, flat, round, rectangular, etc.
• Skin cells are flat, their job is to cover surfaces.
Looking at Cells, continued
Cell size is limited by the surface area-to-volume ratio.
• All substances going in or out must cross the surface of
the cell.
• Cells with greater surface area-to-volume ratios (small
cells) exchange substances more efficiently.
Things have to travel
further in big cells.
Relationship between Surface Area and Volume
Area = (side)2
Volume = (side)3
Volume increases faster than surface area.
Cell Features
All cells have…
1. Cell membrane = outer layer of a cell surface. It is a
barrier between the environment and inside the cell.
1. Cytoplasm = the region of the cell inside the cell
membrane. The fluid portion is called the cytosol.
Cell Features, continued
3. Ribosome = a cellular structure that makes proteins.
4. DNA = instructions for making proteins, regulates cellular
activities, and enables cells to reproduce.
Features of Prokaryotic and Eukaryotic Cells
What are 2 obvious differences between these cells?
internal structures, pili, etc.
Prokaryotic Cells
Features
• Earliest cells (3.5 billion years)
• Very small
• A prokaryote = BACTERIA!!!!!!!
Prokaryotic Cells
Features
• Prokaryotic cells do not have internal compartments. The
DNA is a single loop.
9/7 Bell Work
What is the next number in the sequence?
• 0, 1, 1, 2, 3, 5, 8, 13, 21 _____________
9/7 Schedule
• Notes Ch 7.1 “Intro to Cells” and 7.2 “Inside the Eukaryotic
Cell”
• Start working with Microscopes
• Work Time
• Organic Molecules Notes Chart
• DR Ch 7 “Cells”
Assignments:
1. Dir Rdg “Water” and “Chemistry” – LATE
2. Molecules Note Chart and Menu - TODAY
Eukaryotic Cells
Features
• A eukaryote is made up of eukaryotic cells.
• These cells have membrane-bound organelles, small structures that
have specific jobs.
• The DNA is in an organelle called the nucleus.
Nuclei in onion cells.
Cell Features, continued
The organization of these cells lets them to carry out more
specialized functions than prokaryotic cells.
Metric Review
• What is the base unit for µm?
• “micro” = 1/1,000,000
• 1,000,000 µm = 1 m
• 1,000 µm = 1 mm
Ch 7.2 Inside the Eukaryotic
Cell
Objectives:
• Describe organelle structures and functions.
Structure Review
Where is the nucleus? Why did you pick this structure?
Human skin cells
Outside the cell
Cell Membrane
• Controls movement in and out of the cell
• Double layer
Cell Wall
• OUTSIDE the cell membrane
• Usually found in bacteria, plants, or fungi
• Cell protection and support
Inside the Cell
Nucleus
• Contains the DNA
• Directs cell activities
• Separated from cytoplasm by the nuclear
membrane
Nuclear Membrane
• Controls movement in and out of the nucleus
• Double layer
Inside the Cell
Chromosomes
• In the nucleus
• Made of DNA
• “X” shape when dividing
Nucleolus
• In the nucleus
• Contains RNA to make proteins
Karyotype of girl with Downs.
Inside the Cell
Cytoplasm
• Gel-like mixture inside the cell membrane
• The fluid part is cytosol
Cytoskeleton
• Made of protein fibers
• Help cells move, keep its shape
• 3 kinds of fibers (microfilaments, microtubules,
and intermediate fibers)
Microtubules moving
chromosomes during
mitosis.
Care and Use of Microscopes
• Get the microscope lab packet.
Sketch a microscope on the back
of the first page. Look up what
each part does if needed!
• Always carry scopes with both
hands, one on the base and one
holding the arm.
9/8 Bell Work
Four men sat down to play,
They played all night to break of day.
They played for gold and not for fun
With separate scores for everyone.
When they came to square accounts,
They all had made quite fair amounts.
Can you the paradox explain,
If no one lost, how all could gain?
9/8 Schedule
• Notes 7.2 “Inside the Eukaryotic Cell”
• Microscope Lab
• Work Time
• Organic Molecules Notes Chart
• DR Ch 7 “Cells”
Assignments:
1. Dir Rdg “Water” and “Chemistry” – LATE
2. Molecules Note Chart and Menu - LATE
Inside the Cell
Ribosomes make proteins
• 2 types
• “Free” ribosomes make proteins needed inside the cell
• “Bound” ribosome proteins are exported outside the cell.
• Can switch types depending on what proteins are needed.
Inside the Cell
Endoplasmic Reticulum
• Moves materials around
• 2 Types
• Smooth ER – making lipids and break down toxins
• Rough ER – producing proteins needed outside the cell
Inside the Cell
Golgi Bodies
• Set of flattened sacs
• Moves materials in the cell
• “Packaging Plant” to move proteins and other materials out of
the cell
Inside the Cell
Mitochondria
• Produces energy by breaking down fats and carbs to make ATP
• Controls water levels in cell
• Recycles old protein, fat, and carb molecules
Inside the Cell
Chloroplast
• USUALLY found in plant cells
• Contain a green pigment called chlorophyll
• Where photosynthesis happens and makes ATP
Inside the Cell
Vesicle/Vacuole
• Membrane sacs for storage, digestion, and waste removal.
• Contains water solution
• Helps plants stand up and keep shape
Inside the Cell
Lysosome
• Special kind of vacuole
• Cell “stomach” that breaks down proteins, fats, and carbs
• Transports uneaten materials to the membrane and dumps it
outside the cell.
Exocytosis
Care and Use of Microscopes
• Carry scopes with both hands, one on the base and one
holding the arm.
• ALWAYS start with shortest lens!
• Slides are glass rectangles. Coverslips are plastic squares.
• Work in same pairs as yesterday.
• Finish “e” today, threads if possible.
9/9 Bell Work
• Which is greater? Do not to use a calculator.
2% of $1,000,000
or
25% of $2,400
9/9 Schedule
• Microscope Lab
Assignments:
1. Dir Rdg “Water” and “Chemistry” – LATE
2. Molecules Note Chart and Menu – LATE
3. Dir Rdg “Cells” -- TBA
Care and Use of Microscopes
• Carry scopes with both hands, one on the base and one
holding the arm.
• ALWAYS start with shortest lens!
• Slides are glass rectangles. Coverslips are plastic squares.
• Work in same pairs as yesterday.
• Finish “e” today, threads if possible.
9/12 Bell Work
• What goes up and down the stairs without moving?
9/12 Schedule
• Finish Microscope Lab – due TODAY
• Label/Color Cell Diagrams
Quiz Ch 7.1-7.2 TUESDAY
Assignments:
1. Dir Rdg “Cells” – TBA
2. Microscope Lab – TODAY
3. Cell Diagrams - WEDNESDAY
9/13 Bell Work
• What can you catch but not throw?
Hint: Over winter break I caught a _____. It was horrible!
9/13 Schedule
• Questions on cell structures/functions?
• Notes Ch 7.3
• Label/Color Cell Diagrams
Quiz Ch 7.1-7.2 TODAY
Assignments:
1. Dir Rdg “Cells” – TBA
2. Microscope Lab – LATE
3. Cell Diagrams - WEDNESDAY
Ponder this…
What type of society would you prefer to live in: one in which
you must do everything for yourself, including growing and
gathering food, building shelter, etc., or one in which each
person does the job that they do best?
What are some advantages to having each person do a
specialized job?
What are some advantages to doing everything yourself?
Diversity in Cells
Diversity in Prokaryotes
• Can vary in shape, the way they obtain and use energy,
and movement.
• Movement = flagellum
• a long, hair-like structure that grows out of the cell.
Diversity in Cells
Diversity in Prokaryotes
• Prokaryotes may also have pili,
• short outgrowths of cell wall
• allow the cell to attach to surfaces
• exchange DNA plasmid
Conjugation
Endosymbiosis
Where did eukaryotes come from…?
• Endosymbiosis: 1 cell eats, but did not digest another.
Endosymbiosis
Evidence
• Mitochondria and chloroplasts have their own distinct DNA.
• Many cells eat by endocytosis (phagocytosis)
Mitochondrial DNA is passed only
from the mother.
Endosymbiosis
Phagocytosis in Action… Amoeba vs Paramecium
Endocytosis … Immune system
9/14 Bell Work
• What gets wetter and wetter the more it dries?
9/14 Schedule
• Notes Ch 7.3
• Look at Adipose and Epithelial tissues
• Work time
• Label/Color Cell Diagrams due TODAY
• Dir Rdg Ch 7 “Cells” due FRIDAY
Assignments:
1. Cell Diagrams – TODAY
2. Dir Rdg “Cells” – FRIDAY
Diversity in Cells, continued
Eukaryotic Cell Specialization
• Cells can vary in shape and external features.
• Organelles also vary.
• Muscle cells, which use large amounts of energy, contain
many mitochondria.
Diversity in Cells, continued
Eukaryotic Cell Specialization
• Organelles also vary.
• Plants and animals are similar, but plants also have
chloroplasts, a central vacuole, and a cell wall.
Levels of Organization
Cells in plants and animals are highly organized.
• Tissue is a distinct group of similar cells that perform a
common function.
• Organ is a collection of tissues that work together to
perform a specific function.
• Organ system is composed of a group of organs that work
together to perform major body functions.
Organization in Multicellular
Organisms
Click to animate the image.
Body Types
• Unicellular organisms: thrive independently or live
together in groups.
• Colonial organisms: cells that are permanently
associated but do not work together or integrate cell
activities.
Volvox, a colonial algae
Volvox
• Watch this colonial algae spin!
Body Types
A multicellular organism: many, permanently associated
cells
• coordinate their activities.
• Distinct types of cells have specialized functions to help the
organism survive.
• True multicellularity occurs only in eukaryotes.
Human skeletal muscle
Human epithelial tissue (skin)
Body Types, continued
• Multicellular =interdependent.
• Individual cells cannot survive alone
• Multicellular organisms begin as a single cell, which
divides to form more cells.
• Cells grow and become specialized in differentiation.
Human Tissues
Look at 2-3 different kinds of tissue. Put the answers in your
notebook.
• What is the function of the tissue?
• Do all of the cells look the same? Why or why not?
• Draw the cells and label low and med/high power.
Secret Social Lives of Bacteria
• Watch Bonnie Bassler talk “The Secret Social Lives of
Bacteria.”
• OR… search for it on ted.com
http://www.ted.com/talks/bonnie_bassler_on_how_bacteria_comm
unicate
9/21 Bell Work
A typist increased her speed from 60 words per minute to 75
wpm.
• What percent did her speed increase?
9/21 Schedule
• Test Prep in Groups
• Use book, notes, talk to group
• Very similar test questions, so figure it out!
• NO PARTNER on test!!
• Work Time
• Dir Rdg 7.3 due TODAY, all other assignments LATE
Expect Ch 7 “Cells” test TUESDAY
Assignments:
1. Dir Rdg “Inside Eukaryotic” LATE
2. Cell Diagrams LATE
3. Cell City Analogy due LATE
9/22 Bell Work
Sid Shady is in prison planning his escape. The cell is 3 x 3
x 3 meters. The walls are reinforced concrete and extend
2 m below the dirt floor. The only openings are a locked
door and a skylight. Sid has a plan and starts digging. He
can’t tunnel out, but it’s crucial to his plan.
• How does he hope to escape?
9/22 Schedule
• Any specific questions on material?
• Ch 7 Test
• Use notes, Cell Diagrams, and Molecules note chart, but NO
OPEN BOOK!
• Quiet until all tests are in.
• Finish any missing assignments
Assignments:
1. Dir Rdg “Inside Eukaryotic” LATE
2. Cell Diagrams LATE
3. Cell City Analogy due LATE
Human Tissues Revisited
Look at 2-3 different kinds of tissue. Put the answers in your
notebook.
• Describe the function of the tissue.
• Do all of the cells look the same?
• Draw the cells and label low and med/high power.
Tissues and Organisms
Revisited
Look at 3 different kinds of tissue or organisms. Put the answers
in your notebook.
• Describe the function of the tissue.
• Do all of the cells look the same?
• Draw the cells and label low and med/high power.
• ID cells as plant or animal. Explain.
Human Cheek Cell Sheet
• Use pictures below for cheek cells.
• Answer the questions. You can use your notes.
• Turn in.
100x
400x
Cell Analogy
• Come up with an analogy. Cells are like __________.
• Draw a picture.
• Label organelles and describe their function.
Cells are like the science classroom.
Nucleus = Ms. Olson
She gives instructions.
Wall = cell membrane
It controls what goes in
and out.