Cells and Organelles (Learning Objectives)faculty.sdmiramar.edu/bhaidar/Bio 130/lectures/Cells and...
Transcript of Cells and Organelles (Learning Objectives)faculty.sdmiramar.edu/bhaidar/Bio 130/lectures/Cells and...
Cells and Organelles (Learning Objectives)
• Prokaryotic and eukaryotic cells.
• The three Domains of living organisms.
• 6 emergent feature of living cells and organisms.
• Terminology: gamete, zygote, somatic cells, and germ cells.
• Structure of membranes and intra-cellular compartments.
• Structure and functions of organelles:
a. Plasma membrane b. Cytoskeleton c. Nucleus d. Endoplasmic
reticulum (smooth and rough) e. Golgi apparatus & vesicles
f. Lysosomes g. Peroxisomes h. Mitochondria
• Coordination of functions of several organelles that bring about
cellular functions such as secretion and flow of genetic
information from DNA to protein
Types of Cells on Earth
Prokaryotic cells
- Lack a nucleus
Eukaryotic cells
- Possess a nucleus
and other organelles
Figure 2.2
Domains of Life
Three broad categories of organisms
• Archaea – Unicellular prokaryotes
• Bacteria – Unicellular prokaryotes
• Eukarya – Includes both unicellular and
multicellular eukaryotes
Atoms/Elements
Molecules
Organelle
Cell
Tissue
Organ
Organ system
Organism
(Family)
Population
Community
Ecosystem
Biosphere
Chemical world
Bio
logic
al W
orld
Non-living
Living
Ascending
Descending
Emergent properties of life shared by cells and all
levels if the biological organization
• Order
• Regulation of internal conditions (Homeostasis)
• Growth and development
• Energy use
• Response to environmental stimuli
• The ability to reproduce
Basic concepts
• Cells Interact:
send, receive, respond to signals
aggregate to form tissues, organs and organ
systems
• Health state- balance between cell
division and cell death
• Specialization of cell function- expression
of different subsets of genes.
Human Development
Sperm cell
NucleicontainingDNA
Egg cell
Fertilized eggwith DNA fromboth parents
(Zygote)
Embyro’s cells with copies of inherited DNA
Offspring with traitsinherited fromboth parents
Unspecialized
replicating
cells
Different
specialized
cells
Human Cells
Gametes: • sperms and eggs• haploid
Zygote• diploid
Somatic cells: • body cells • diploid
Germ cells:• gonad cells that
produce gametes• diploid
Mitosis and
development
Multicellular
diploid adults
(2n = 46)
Diploid
zygote
(2n = 46) 2n
Meiosis Fertilization
Egg cell
Sperm cell
n
Haploid gametes (n = 23)
n
• Cellular activities and abnormalities
underlie our inherited traits, quirks, and
illnesses Lack of
dystrophin
Muscular Dystrophy
A cell is a living unit greater than the sum of its parts
Basic Features of an animal cell
• Boundary-plasma membrane
• Cytoplasm: Compartment (division of labor)
o Cytosol (soluble components)
o Organelles surrounded by membranes to
partition functions
• Nucleus DNA-information
Smooth endoplasmicreticulum
Roughendoplasmicreticulum
CYTOSKELETON:
NUCLEUS:
Nuclear envelope
Chromosomes
Nucleolus
Ribosomes
Golgiapparatus
Plasma membrane
Mitochondrion
Peroxisome
Centriole
Lysosome
Microtubule
Intermediatefilament
Microfilament
Role of cell membranes in compartmentalization of cellular
functions
Hydrophilic
head
Hydrophobic
tail
Figure 2.8
A phospholipid bilayer
- Phosphate end
(hydrophilic)
- Fatty acid chains
(hydrophobic)
Compartmentalized functions of animal cells
• Manufacturing, processing, and shipping of
molecules to appropriate destination: – DNA, proteins, carbohydrates, lipids
• Breakdown of molecules:
– large structures, lipids, detoxification of certain
substances
• Energy processing:
– forming cellular energy form
• Structural support, movement, and
communication
Figure 2.3
Plasma Membrane
Forms a selective barrier
Contains proteins,
glycoproteins, and
glycolipids
- Important to cell function
and interactions
- May be receptors
- Form channels for ions
Figure 2.3
Inherited Diseases caused by
Faulty Ion Channels
Sodium channels
- Mutations lead to absence or extreme pain
Potassium channels
- Mutations lead to impaired heart function and
one form of deafness
Chloride channels
- Mutations lead to cystic fibrosis
Clinical Connections 2.2, page 26
Figure 2.3
Cytoskeleton
A meshwork of protein
rods and tubules
Includes three major
types of proteins
- Microtubules
- Microfilaments
- Intermediate filaments
Figure 2.11
Figure 2.3
Cytoskeleton Functions
• Maintain cell shape
• Connect cells to each other
• Transport organelles and small molecules
• Provide cell motility (some cell types)
• Move chromosomes in cell division
• Compose cilia
Genetic disorders of the cytoskeleton?
Figure 2.3
Inherited Disease caused by faulty connections
between the plasma membrane and the
cytoskeleton
Hereditary Spherocytosis
Figure 2.3
The Nucleus
The largest structure in a cell
Surrounded by a double-layered nuclear
envelope
Contains:
- Nuclear pores that allow movement of some
molecules in and out
- Nucleolus, which is the site of ribosome
production
- Chromosomes composed of DNA and
proteins
Figure 2.3
Figure 2.4
The Nucleus
Figure 2.3
Endoplasmic Reticulum (ER)
Interconnected membranous tubules & sacs
Winds from the nuclear envelope to the
plasma membrane
Rough ER contains ribosomes and is
involved in protein synthesis
Smooth ER does not contain ribosomes
and is important in lipid synthesis
Figure 2.3
Golgi Apparatus
Stack of flat membrane-enclosed sacs
Processing center of added sugars that form
glycoproteins and glycolipids
Site of final protein folding
Products are released into vesicles that bud
off to the plasma membrane
Secretion
Coordination
of function of
organelles
Figure 2.5
Protein Traffickinghttp://vcell.ndsu.edu/animations/proteintrafficking/movie-flash.htm
Transport vesiclebuds off
Secretoryproteininside trans-port vesicle
Glycoprotein
Polypeptide
Ribosome
Sugarchain
Rough ER
1
2
3
4
Nucleus
VacuoleLysosome Plasma membrane
Smooth ER
Nuclearmembrane
Golgiapparatus
Rough ER
Transportvesicle
Transportvesicle
Figure 2.3
Lysosomes
Membrane-bound sacs
containing > 40 types
of digestive enzymes
Break down bacteria,
cellular debris, and
nutrients
Tay-Sachs is an
inherited lysosomal
storage disorderhttp://www.ygyh.org/tay/whatisit.htm
Figure 2.6
Lysosomes• Membrane-bounded sacs of hydrolytic enzymes
that digestive enzymes
http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter5/animations.html#
Figure 2.3
PeroxisomesSacs with one membrane filled with several types of
enzymes
- Break down lipids, rare biochemicals
- Synthesize bile acids
- Detoxify compounds from free radicals, H2O2, and
alcohol
- Abundant in liver and kidney cells
Lorenzo’s oil
Adrenoleukodystrophy absence of a peroxisomal enzyme leads
to accumulation of long-chain fatty acids in brain and spinal
cord
Figure 2.3
Mitochondria
Surrounded by two
membranes
Site of ATP (energy)
production
Contain their own
circular DNA
Human mitochondrial
DNA is inherited
only from the mother
Lou Gehrig Disease
Figure 2.7
Structures and Functions of
Organelles
Table 2.1
Prokaryotic & Eukaryotic Animal and Plant cells
http://www.wisc-online.com/objects/index.asp?objID=AP11604
Secretion
http://www.youtube.com/watch?v=MrHULUxAsGg