Transcript Cell Biology

Cell Biology
Ms Mahoney
MCAS Biology
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.2 Compare and contrast, at the cellular level,
the general structures and degrees of
complexity of prokaryotes and eukaryotes.
Prokaryotes
Eukaryotes
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Simple
Single Celled
DNA exposed
No Organelles
• Asexual Reproduction
– Binary fission
Complex
Single or Multi celled
DNA protected
Organelles (smaller
parts)
• Sexual Reproduction
– Meiosis
Cell Biology
• Central Concepts: Cells have specific structures and functions
that make them distinctive. Processes in a cell can be classified
broadly as growth, maintenance, and reproduction.
• 2.1a Relate cell parts/organelles (plasma membrane, nuclear
envelope, nucleus, nucleolus, cytoplasm, mitochondrion,
endoplasmic reticulum, Golgi apparatus, lysosome, ribosome,
vacuole, cell wall, chloroplast, cytoskeleton, centriole, cilium,
flagellum, pseudopod) to their functions.
ALL Cells Have these Parts
Structure
Function
• Cell Membrane
• Keep material in or
out of the cell
• Instructions for the
cell
• DNA
• Cytoplasm
• Ribosomes
• Flagella/Cillia
• Liquid of the cell
• Make proteins
• Movement
Organelles (smaller parts of the cell)
in Eukaryotes
Structure
Function
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Nucleus
Nucleolus
Ribosomes
Rough ER
Hold DNA
Make ribosomes
Make proteins
Makes proteins
– Has ribosomes
• Smooth ER
• Golgi Apparatus
• Lysosome
• Mitochondria
• Makes lipids/breakdown
toxins
• Package and ship proteins
• Break apart materials
• Make energy (ATP)
ONLY Plants Have
Structure
• Cell Wall
Function
• Protection and
shape
• Central Vacuole
• Store water and
other materials
• Chloroplast
• Make sugar
– Photosynthesis
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.3 Use cellular evidence (e.g., cell structure, cell
number, cell reproduction) and modes of
nutrition to describe the six kingdoms
(Archaebacteria, Eubacteria, Protista, Fungi,
Plantae, Animalia).
6 Kingdoms
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Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
Eating
• Heterotroph
– Take in food
• Autotroph
– Make their food
Reproduction
• Asexual
– One cell splits
• Sexual
– Two cells merge
Cell Type
Cell
structure
Cell Number Cell
Nutrition
Reproduction
A. Bacteria
bacteria
Simple
Single
No Organelles
Asexual
Heterotroph
Eubacteria
bacteria
Simple
Single
No Organelles
Asexual
Heterotroph
Protist
ameoba
Complex
Has
Organelles
Single
Asexual
Autotroph or
heterotroph
Fungi
mushroom
Complex
Has
Organelles
Single
or multi
Sexual
Heterotroph
Plant
Complex
Has
Organelles
Single
or multi
Sexual
Autotroph
Animal
Complex
Has Organelles
Single
or multi
Sexual
Heterotroph
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.1b Explain the role of cell membranes as a
highly selective barrier (diffusion, osmosis,
facilitated diffusion, active transport).
Cell Membrane
• Selective barrier
–Controls what enters and leaves the cell
• Made of lipids and proteins
–Lipids: keep water in or out
–Proteins: allows material to pass
through
• Examples :
–Channels
Movement Across the Membrane
• Diffusion
– Definition: movement of material from an area of
“high concentration” to “low concentration”
• High concentration: a lot of material
• Low concentration: small amount of material
Types of Diffusion
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Active diffusion: need energy (ATP)
Passive Diffusion: no energy
Osmosis: diffusion of water
Facilitated diffusion: protein in membrane
helps move material into the cell
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.4 Identify the reactants, products, and basic
purposes of photosynthesis and cellular
respiration. Explain the interrelated nature of
photosynthesis and cellular respiration in the cells
of photosynthetic organisms.
• 2.5 Explain the important role that ATP serves in
metabolism.
ATP (energy)
• Energy for the cell
• Needed for chemical reactions
• Made during cellular respiration
Cellular Respiration
• What is the point of Cellular Respiration?
– TO MAKE ENERGY
• What is happening?
– Sugar (glucose) and oxygen mix together to make
ATP (energy) and carbon dioxide and water
• Formula:
C6H12O6 + O2  CO2 + H2O + energy
• Where does it happen?
– In the mitochondria of all eukaryotes
Photosynthesis
• What is the point of Photosynthesis?
– TO MAKE SUGAR
• What is happening?
– Carbon dioxide and water mix together to make sugar
and oxygen
• Formula:
CO2 + H2O C3H6O3 + O2
(light)
• Where does it happen?
– In the chloroplasts of plants and some protists
Cycle of C02 and O2
Carbon dioxide: CO2 Oxygen: O2
Plants
photosynthesis
CO2 in
the air
O2 in the
air
Animals
Cellular
respiration
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.6 Describe the cell cycle and the process of
mitosis. Explain the role of mitosis in the
formation of new cells, and its importance in
maintaining chromosome number during
asexual reproduction.
Cell Cycle (life of a cell)
Mitosis
Cell divides
G1
G2
growth
growth
Synthesis
DNA 2x
Mitosis
• Make new cells for:
– Asexual reproduction
– Growth
– Repair
• Cells divide once
– Start with one cell, ends with 2 cells
• Amount of DNA stays the same
– Chromosome number stays the same
• Nucleus breaks apart
• Chromosomes line up in
middle of cell
• Chromosomes separate
• New nucleus forms and
cells split
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.7 Describe how the process of meiosis
results in the formation of haploid cells.
Explain the importance of this process in
sexual reproduction, and how gametes form
diploid zygotes in the process of fertilization.
Meiosis
• Division of sex cells
– Gametes
– Sperm and Eggs
• Cell divides twice
• Start with one cell (diploid) and end with 4 cells
(haploid)
– Diploid: two copies of DNA
– Haploid: one copy of DNA
• Sperm and egg come together to make a zygote
– Fertilization makes a new diploid cell
– One DNA copy from mom, one DNA copy from dad
– Each pair is called: homologous chromosomes
• DNA doubles
– Replication
• Meiosis I
– homologous
chromosomes separate
into cells (each copy)
• Meiosis II
– Chromosomes separate
into new cells
• End with four haploid
cells
Cell Biology
• Central Concepts: Cells have specific structures
and functions that make them distinctive.
Processes in a cell can be classified broadly as
growth, maintenance, and reproduction.
• 2.8 Compare and contrast a virus and a cell in
terms of genetic material and reproduction.
Virus
• Not alive
• Needs a host (other living thing) to reproduce
– Why?
– No organelles to make more of its self
• Virus DNA that goes into host DNA and
controls the host cell