3. cellular basis of life
DESCRIPTION
TRANSCRIPT
![Page 1: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/1.jpg)
![Page 2: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/2.jpg)
Do you know that….• The average human being is composed of
around 100 Trillion individual cells!!!• Each cell has about 10,000 times as many
molecules as the Milky Way has stars• Three-hundred-million cells die in the
human body every minute
![Page 3: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/3.jpg)
Discovery of Cells
• 1665- English Scientist, Robert Hooke, discovered cells while looking at a thin slice of cork.
• He described the cells as tiny boxes or a honeycomb
• He thought that cells only existed in plants and fungi
![Page 4: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/4.jpg)
Anton van Leuwenhoek
• 1673- Used a handmade microscope to observe pond scum & discovered single-celled organisms
• He called them “animalcules”• He also observed blood cells from
fish, birds, frogs, dogs, and humans• Therefore, it was known that cells
are found in animals as well as plants
• Father of Microscopy
![Page 5: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/5.jpg)
Development of Cell Theory
• 1838- German Botanist, Matthias Schleiden, concluded that all plant parts are made of cells
• 1839- German physiologist, Theodor Schwann, who was a close friend of Schleiden, stated that all animal tissues are composed of cells.
![Page 6: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/6.jpg)
Development of Cell Theory
• 1858- Rudolf Virchow, German physician, after extensive study of cellular pathology, concluded that cells must arise from preexisting cells.
![Page 7: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/7.jpg)
1. All organisms are composed of one or more cells. (Schleiden & Schwann)(1838-39)
2. The cell is the basic unit of life in all living things. (Schleiden & Schwann)(1838-39)3. All cells are produced by the division of preexisting cells. (Virchow)(1858)
The 3 Basic Components of the Cell Theory
![Page 8: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/8.jpg)
Modern Cell Theory
Modern Cell Theory contains 4 statements, in addition to the original Cell Theory:
1.The cell contains hereditary information(DNA) which is passed on from cell to cell during cell division.
2.All cells are basically the same in chemical composition and metabolic activities.
![Page 9: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/9.jpg)
3. All basic chemical & physiological functions are carried out inside the cells.(movement, digestion,etc)
4. Cell activity depends on the activities of sub-cellular structures within the cell(organelles, nucleus, plasma membrane)
Modern Cell Theory
![Page 10: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/10.jpg)
Modern Microscopes–Types
• Light microscope (400-1000X)• Confocal/Fluorescence microscope (500X)
• Electron microscope (1000-10000X)
![Page 11: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/11.jpg)
MICROSCOPE
![Page 12: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/12.jpg)
The light microscope enables us to see the overall shape and structure of a cell
![Page 13: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/13.jpg)
•combined the laser scanning method with the 3D detection of biological objects labeled with fluorescent markers
•achieves a controlled and highly limited depth of focus
Confocal/Fluorescence microscope
![Page 14: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/14.jpg)
Scanning electron microscope (SEM)
• They use a beam of electrons instead of light– allows greater
magnification – reveals cellular
details-produces an image of the 3D structure of the surface of a specimen
Transmission electron microscope (TEM)
![Page 15: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/15.jpg)
DIVERSITY OF CELLS
![Page 16: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/16.jpg)
Two Fundamentally Different Types of Cells
![Page 17: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/17.jpg)
The PRESENCE OR ABSENCE of a NUCLEUS is
important for Classifying Cells.
![Page 18: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/18.jpg)
Prokaryotes – Domain Bacteria
-> Single cell organisms-> No nucleus, no compartments-> Peptidoglycan cell walls-> Binary fission-> For energy, use organic chemicals, inorganic chemicals, or photosynthesis
![Page 19: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/19.jpg)
-> Lack peptidoglycan-> Live in extreme environments Include:
MethanogensExtreme halophilesExtreme thermophiles
-> Role in disease not well understood—this group has only recently been discovered
Prokaryotes – Domain Archea
![Page 20: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/20.jpg)
Eukaryotes
![Page 21: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/21.jpg)
• Structural Differences– Plants have choloroplasts, a
large central vacuole and a cell wall
– Plant cells do not have centrioles
– Plant cells have plasmodesmata
– Animal cells have gap junctions
• Physiological Differences– Plant cells have
photosynthesis in addition to respiration
– During mitosis a cell plate is formed in plant cells
– Starch is molecule for energy storage while in animal cells it is glycogen
– Large central vacuole stores more water and carbohydrates then animal cell vacuoles
![Page 22: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/22.jpg)
Different Cell Parts
In cells, various specialized functions occur in specific places. These places are called organelles (small organs)
![Page 23: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/23.jpg)
Plasma Membrane
FLUID MOSAIC MODEL
![Page 24: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/24.jpg)
• Cell membrane separates living cell from nonliving surroundings– thin barrier = 8nm thick
• Controls traffic in & out of the cell– selectively permeable– allows some substances to cross more easily
than others• hydrophobic vs hydrophilic
• Made of phospholipids, proteins & other macromolecules
![Page 25: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/25.jpg)
![Page 26: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/26.jpg)
Phospholipid Bilayer• Lipids
– Organic compounds– Fats + Oils– Non-polar– Insoluble in water (Not
attracted to water)Phosphate Head
– Polar– Water-soluble (Attracted to
water)
Phosphate Group
Glycerol Backbone
Water-Soluble
Water-Insoluble
Here is what a phospholipid bi-layer looks like as a sphere
FATTY ACIDS
POLARHEAD
![Page 27: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/27.jpg)
• The internal composition of the cell is maintained because the plasma membrane is selectively permeable to small molecules.
• Only small, relatively hydrophobic molecules are able to diffuse across a phospholipid bilayer at significant rates by using passive diffusion.
Permeability of phospholipid bilayers
![Page 28: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/28.jpg)
Transport Across Membranes
![Page 29: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/29.jpg)
Transport Across Membranes: PASSIVE
DIFFUSIONThe movement of molecules or ions from a region where they are at a high concentration to a region of lower concentration
![Page 30: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/30.jpg)
![Page 31: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/31.jpg)
• Gases (oxygen, carbon dioxide)
• Water molecules (rate slow due to polarity)
• Lipids (steroid hormones)
• Lipid soluble molecules (hydrocarbons, alcohols, some vitamins)
• Small noncharged molecules (NH3)
SIMPLE DIFFUSION
![Page 32: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/32.jpg)
• Ions
(Na+, K+, Cl-)
• Sugars (Glucose)
• Amino Acids
• Small water soluble molecules
• Water (faster rate)
FACILITATED DIFFUSION
![Page 33: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/33.jpg)
How do molecules move through the plasma membrane by facilitated
diffusion?
• Channel and Carrier proteins are specific:• Channel Proteins allow ions, small solutes, and
water to pass• Carrier Proteins move glucose and amino acids• Facilitated diffusion is rate limited, by the
number of proteins channels/carriers present in the membrane.
![Page 34: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/34.jpg)
– Osmosis is the diffusion of water across a differentially permeable membrane.
– Osmotic pressure is the pressure that develops in a system due to osmosis.
OSMOSIS
![Page 35: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/35.jpg)
Concentration of water• Direction of osmosis is determined
by comparing total solute concentrations– Hypertonic - more solute, less water
– Hypotonic - less solute, more water
– Isotonic - equal solute, equal water
hypotonic hypertonic
water
net movement of water
![Page 36: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/36.jpg)
Active Transport
“The Doorman”“The Doorman”
conformational change
• Cells may need to move molecules against concentration gradient– shape change transports solute from
one side of membrane to other – protein “pump”– “costs” energy = ATP
ATP
low
high
![Page 37: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/37.jpg)
![Page 38: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/38.jpg)
![Page 39: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/39.jpg)
![Page 40: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/40.jpg)
Endocytosis
Vesicles form as a way to transport molecules into a cell
a. Phagocytosis Large,particulate matter (Bacteria, viruses, and aged or dead cells).
b. PinocytosisLiquids and small particles dissolved in liquid
![Page 41: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/41.jpg)
Exocytosis Vesicles form as a way to
transport molecules out of a cell
![Page 42: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/42.jpg)
Cytoplasm
• Thick, clear liquid residing between the cell membrane holding organelles
•many of the complex chemical reactions/ metabolic pathways take place here such as:
Glycolysisgluconeogenesis biosynthesis of sugars, fatty acids, and amino acids
![Page 43: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/43.jpg)
Mitochondria* site of cellular respiration * POWERHOUSE OF A CELL
Where energy is released from nutrients* there are MANY in a single cell* has two layers, makes up a double membrane
![Page 44: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/44.jpg)
Act similar to electric power plant
Up to 300 to 800 per cell
Come from cytoplasm in EGG
You inherited your mitochondria from your mother
![Page 45: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/45.jpg)
certain organelles originated as free-living bacteria that were taken inside another cell as endosymbionts. Mitochondria developed from proteobacteria
Can replicate itself: BINARY FISSION
ENDOSYMBIOSIS
![Page 46: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/46.jpg)
(1) outer membrane It is fairly smooth. It is composed of
phospholipid bilayer protein.
it has channel protein: hole protein , permit that small molecule substance freely pass.
The ultrastructure of mitochondrion
![Page 47: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/47.jpg)
(2)inner membrane they are more proteins than phospholipids.it has no hole protein , so penetrability is weak.
![Page 48: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/48.jpg)
(3) intermembrane space it contains enzymes. It can
catalyze ATP to create ADP.
(4)MatrixEnzymes are abundant in the matrix . It also contains mitochondrial genetic system including DNA and ribosome.
(5) elementary particle it also call ATP synthase.
it lies in the inner membrane.
![Page 49: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/49.jpg)
The Functions of mitochondrion
•Production of ATP through respiration•cellular metabolism
citric acid cycle or the Krebs Cycle
![Page 50: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/50.jpg)
Chloroplasts
chloroplastsin plant cell
cross sectionof leafleaves
chloroplast
absorbsunlight & CO2
makeenergy & sugar
chloroplastscontainchlorophyll
CO2
![Page 51: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/51.jpg)
Structure
• Chloroplasts– double membrane– stroma
• fluid-filled interior– thylakoid sacs– grana stacks
• Thylakoid membrane contains– chlorophyll molecules– electron transport chain
outer membraneinner membrane
thylakoidgranum
stroma
![Page 52: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/52.jpg)
![Page 53: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/53.jpg)
Nucleus* surrounded by a nuclear membrane
* only found in EUKARYOTES
* contains genetic material (DNA) in the form of chromosomes that controls the activities of the cell
* serves as the information and administrative center of the cell
![Page 54: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/54.jpg)
![Page 55: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/55.jpg)
•Nucleoplasm•Nuclear envelope•Nuclear pores•Chromatin
DNA + associated proteins
•Nucleolus internal structure of
nucleus, site of ribosome assembly•Chromatin vs. Chromosome
Nucleus: Structure
![Page 56: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/56.jpg)
The Major Functions of the Nucleus
•stores the cell's hereditary material, or DNA•coordinates the cell's activities
-intermediary metabolism-growth-protein synthesis-reproduction (cell
division)
![Page 57: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/57.jpg)
Endoplasmic Reticulum (ER)- a series of interconnecting channels associated
with storage, synthesis, and transport of substances within the cell
two types:A) rough--the 'ER' studded with ribosomesB) smooth--the 'ER' without any ribosomes
![Page 58: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/58.jpg)
Rough endoplasmic reticulumproduction and processing of
specific proteins at ribosomal sites.
![Page 59: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/59.jpg)
![Page 60: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/60.jpg)
•carbohydrate metabolism•regulation of calcium ions•synthesis of steroids and lipids•drug detoxification•metabolism of steroids
Smooth endoplasmic reticulum
![Page 61: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/61.jpg)
RibosomesProtein Synthesis"translates" the genetic information from ` RNA into proteins
![Page 62: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/62.jpg)
•looks like a stack of flattened pancakes
• All of the proteins and lipids synthesized by the RER and SER are sent to the golgi.
•sorts, modifies, and packages the products of the RER and SER before sending them to their final destination inside or outside of the cell.
Golgi Apparatus
![Page 63: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/63.jpg)
![Page 64: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/64.jpg)
![Page 65: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/65.jpg)
Vacuole" a "space" in a cell that contains water or other materials; usually for storageA) food vacuoles--store foodB) contractile vacuoles-- squeeze out excess water
![Page 66: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/66.jpg)
Centrioles
•found in animal cells; rare in plants•cylindrical structures (like cans) found in the cytoplasm that appears to function during cell division (reproduction) •involved in the organization of the mitotic spindle and in the completion of cytokinesis
![Page 67: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/67.jpg)
Cell Wall•found mostly in plant cells (some monerans, protists, and fungi too)•a non-living structure which surrounds and supports a cell•made of cellulose, a complex carbohydrate
![Page 68: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/68.jpg)
Lysosome “Suicidal bags of the cell”a vacuole that contains digestive
enzymes; helps in the process of nutrition by breaking down nutrients in the cell
![Page 69: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/69.jpg)
Peroxisomes•helps to rid the body of the host organism of toxins•breakdown of very long chain fatty acids through beta-oxidation
![Page 70: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/70.jpg)
Cilia and Flagella•these are hair-like organelles that extend from the surface of many different types of cells
A)cilia--are typically smaller than flagella, but they cover the outside of the organismB)flagella--are much longer than cilia, but there usually are few on a single cell
•these structures usually aid in movement•they can also help sweep materials along the outside of a cell
![Page 71: 3. cellular basis of life](https://reader036.vdocument.in/reader036/viewer/2022081413/546f16daaf7959330b8b52e6/html5/thumbnails/71.jpg)