phylogeny, taxonomy, cells and tissues. phylogeny & taxonomy phylogeny –evolutionary...
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Phylogeny, Taxonomy, Phylogeny, Taxonomy, Cells and TissuesCells and Tissues
Phylogeny, Taxonomy, Phylogeny, Taxonomy, Cells and TissuesCells and Tissues
Phylogeny & Taxonomy
• Phylogeny– Evolutionary relationship of animal groups– Established by comparative study of homologies
• Anatomical• Embryological• Molecular
• Taxonomy– Naming of groups– Based on phylogenic relationships and
homologies at Domain, Kingdom, Phylum level– Based on individual traits at Genus & species level
Taxonomic Groups
Domain
Kingdom Phylum
Class
Order
Family
Genus
Species
• Archae, Bacteria, Eukarya• Animalia, Plantae, Protista,
Fungi• 11 major & 9 minor phyla of
Animalia
• Genus species binomial nomenclature used to specifically identify organisms
Taxonomy of Humans
Domain EukaryaKingdom Animalia
Phylum Chordata
Class Mammalia
Order Primates
Family Hominidae
Genus Homo
Species sapiens
Phylogeny of Kingdom Animalia
Protostomes Deuterostomes4
Deuterostome development,EndoskeletonProtostome development 4
Mo
ll us c
a
5
Tissues1
Parazoa Eumetazoa1
No true tissues
Po
rife
ra(s
po
ng
es)
Radiata Bilateria2
Bilateral symmetryRadial symmetry 2
Rad
iat a
(C
nid
aria
and
Ct e
no
ph
ora
)Acoelomates Pseudocoelomates Coelomates3
Body cavityNo body cavity 3
Pla
tyh
elm
inth
es(f
latw
orm
s)
CoelomPseudocoel
Nem
ato
da
(ro
un
dw
orm
s)
Ro
tife
ra(r
oti
fers
)?
Lo
ph
op
ho
rate
s
Jointed appendages,Exoskeleton
Segmentation
Segmented
5
An
nel
ida
Ar t
hr o
-p
od
a
Segmented
Notochord,Pharyngeal arches, Dorsal nerveE
chin
od
erm
ata
Ch
ord
ata
Ancestral protist
Multicellularity
Two Types of Cells
• Prokaryotic– Domains bacteria and archaea
• No nucleus or membranous organelles• Typically small < 10m• Single circular chromosome
• Eukaryotic– Domain eukarya
• Have a nucleus (sometimes more than 1)• Have numerous membranous organelles• Larger than 20 m (usually >100 m)• Multiple, linear chromosomes within nucleus
Animal Cell
Nucleus• Houses chromosomes - DNA• Transcription – production of RNA from DNA• Key components
– Nuclear membrane– Nucleoplasm– Chromatin threads– Nucleolus
Nucleus
Gene Expression
DNA
transcribed
RNA
translated
Protein
DNA Genes Chromatin Chromosomes
Chromosome
• Each chromatid is a DNA double helix
• Aggregate of genes
Sister
Mitosis
Cell Membrane
• Encloses cell
• Regulates entry/exit of materials
Endoplasmic Reticulum
• Ribosomes – protein synthesis
• ER – processing of proteins
Golgi Apparatus
• Processing of proteins for secretion
Production & Secretion of Proteins
Mitochondrion
• Production of ATP
• ATP used to activate proteins
Cellular Organization
• Cells
• Tissues – similar cells are organized to perform common functions.
• Organs – tissues are assembled organs which perform specific functions
• Animal
Major Tissue Types
Muscle Tissue
• 3 major types– Cardiac– Skeletal (striated)– Smooth
• Major proteins– Contractile proteins
• Actin• Myosin
Muscle Tissue: Skeletal
• Multinucleated cells • Attached to bones
• Main function is movement
Muscle Tissue: Cardiac
• Striations, but unfused cells
• Located in heart• Function is
contraction the heart
Muscle Tissue: Smooth• Mononucleate• Located in GI tract, uterus, urinary bladder and
blood vessels.• Propulsion of materials
Connective Tissues
• Adipose – support, protection, conservation of heat and energy storage.
• Areolar – anchors blood vessels, nerves and organs.• Cartilage – flexibility and support• Bone – protection, support and muscle attachment• Blood – transport oxygen / CO2, clotting and immune
response
• Extracellular matrix– Collagen – forms cable-like fibers or sheets that provide tensile
strength.– Elastin – rubber like protein fiber that abundant in flexible
tissues.– Fibronection – promotes cell adhesion and anchorage.
Connective Tissue: Areolar
Connective Tissue: Adipose
Connective Tissues: Cartilage & Bone
Cartilage
Bone
Connective Tissue: Blood
• Erythrocytes – red blood cells
• Leukocytes – white blood cells
• Platelets
Epithelial Tissue
• Tightly connected cells
• Line exterior of body
• Line interior of cavities– Gut, blood vessels, lymph vessels, glands
• Secretion– Sweat– Digestive enzymes– Milk
Epithelial Tissues
Neural Tissue
• Composed of highly specialized cells called neurons that transmit electrical impulses across junction called synapses.
• Total number is fixed at birth.