Growth & DevelopmentTransition from 1 cell to multi-cellular organism

Timeline

• Fertilization Sperm & egg join to form zygote• Cleavage rapid cell division•:

• Fertilization Sperm & egg join to form zygote

• Cleavage rapid cell division• Morula: • 16 cells

• Blastula:• 128 cells

Timeline (cont)

Differentiation transition from general to specialized Totipotent▪ Ability to form all cell/tissue types▪ Ex: zygote

Pluripotent▪ Ability to form many cell types▪ Stem cells▪ blastula

Timeline (cont) Gastrula

3 layered embryo Ectoderm:▪ Outer layer▪ Skin, nervous system, outer openings

Endoderm:▪ Inner layer▪ Organs (lungs, digestive tract, etc.)

Mesoderm▪ Middle layer▪ Muscles, bone, blood, fat

Tissues

Epithelial Inner/outer lining Regulation

Connective Between other tissues Support & structure

Muscle On bones & w/in organs Movement

Nervous Thru-out body Respond to stimuli

Epithelial Tissue

Classification # of cells▪ Simple (1 layer)▪ Stratified (>1 layer)▪ Psuedostratified

Shape▪ Cuboidal (square)▪ Columnar (rectangular)▪ Squamous (flat tiles)

Connective Tissue

Classification types of fibers Dense

(collagenous)▪ Strong durable

Elastic▪ Flexible, stretch

Loose (reticular)▪ Thin, branched

Connective Tissue (cont)

Types Areolar (surround organs) Adipose (protect) Fibrous▪ Tendons (MB)▪ Ligaments (BB)

Cartilage Bone Blood

Muscle Tissue

Classification Striations (stripes) Voluntary/Involuntary

Types Skeletal▪ Striated▪ Voluntary▪ Found on bones

Muscle Tissue (cont)

Cardiac▪ Striated▪ Involuntary▪ Heart

Smooth▪ No striations▪ Involuntary▪ Lines organs

Nervous Tissue

Transmit electrical impulses

Dendrite Conduct

electrochemical signals w/in nervous system

Axon Transmission of

signals from nervous to other tissues

Organs

Built from 2/more types of tissues