Bio 111 Ch 51+20

What is development?

a series of changes in the state of a cell, tissue, organ, or organism.

What is the difference between development and growth?

Development produces organisms with a defined set of characteristics and growth produces more or larger cells

What is the structure or form of an organism called?

morphology

How many axes are the body plan?

3 axes: dorsoventral axis, anteroposterior axis, and left-right axis

What are plants body plans?

root/shoot axis, radial patterns

How are morphogens distributed?

asymmetrically along a concentration gradient; giving positional information

Where morphogen gradients established?

first in the oocyte and later in the embryo by secretion and transport

True or false most animals are triploblastic?

true

What are the 3 cell layers of embryos?

endoderm, mesoderm, and ectoderm

What are the five events of embryogenesis?

fertilization, cleavage, gastrulation, neurulation, and organogenesis

What extra step may be included in embryonic development

metamorphosis of larva to adult after organogenesis

What are the stages of vertebrate development

fertilization, cleavage, gastrulation, neurulation, organogenesis, and adulthood

What reaction is required for fertilization?

acrosomal

What type of reaction blocks polyspermy?

cortical

What is cleavage?

repeated cell divisions without cell growth

What organisms go through meroblastic cleavage?

Birds and fishes

What type of cleavage is meroblastic cleavage?

incomplete

What is the vegetal pole?

where yolk is more concentrated in the egg

What is the animal pole?

where there is less yolk and more cytoplasm in the egg

What organisms go through holoblastic cleavage?

amphibians and mammals

What type of cleavage is holoblastic cleavage

complete

In what stage does blastula become gastrula?

gastrulation

What happens in the ectoderm?

the epidermis and nervous system are formed

What happens in the mesoderm?

the heart, limbs, muscles, kidneys, blood, connective tissues, and notochord are formed

what happens in the endoderm?

epithelial lining of the gut, liver, pancreas, thyroid, lungs, and bladder are formed

What does neurulation create?

the CNS (central nervous system) from ectoderm

Where doe neurulation begin?

the formation of neural tube from ectoderm located dorsal to notochord

Where do neurons and their supporting cells originate from?

neural precursor cells derived from neural tube

How does the neural tube form?

thickening and elongation, folding, convergence, and fusion