Invert Development Flashcards
Define Metazoan
Any animal that undergoes development from an embryo stage with three tissue layers, namely the ectoderm, mesoderm, and endoderm. Any animal that is multicellular.
Name the 7 typical features of metazoan development
- Fertilization
- Cleavage
- Gastrulation
- Differentiation
- Organogenesis
- Morphogenesis
- Growth and Sexual Maturation
Define Fertilization and name the product of it
New individuals created from the fusion of two gametes. Product is a Zygote
Define Cleavage and name the product of it
Zygote undergoes rapid mitotic division. Cytoplasm divided into many smaller cells (Blastomeres)
Define Morula
Cluster of Blastomeres
Define Blastula
Hollow ball of cells with central cavity
Define Gastrulation and name the 3 products of it
Cells of blastula undergo rearrangement into the 3 Germ Layers:
- Endoderm: Inside embryo
- Ectoderm: Surface of embryo
- Mesoderm: between endo and ectoderm
Define Differentation
Cells in different germ layers giving rise to distinctive types of tissues
Into what 2 things does the Ectoderm differentiate?
- Most of nervous system
- Surface of skin
Into what does the Endoderm differentiate?
Epithelial lining and associate organs
Into what 4 things does the Mesoderm differentiate?
- Muscle
- Blood
- Bone
- Connective Tissues
Define Organogenesis
Cells from the same and differnt germ layers interact and rearrange to produce organs
Define Morphogenesis
Aquisition of form/shape; typically coincides with organogenesis
Define growth and Sexual Maturation as they relate to Metazoan development
Organism grows in size via Mitosis until it reaches sexual maturity and initiates Gametogenesis
Define Gametogenesis
Gametes are produced by Germ Cells
Define the Germ line/Germ cells
Special cells set aside early during development that produce gametes
Define Somatic Cells
All cells that are not germ cells
Name 6 approaches to understanding development
- Observation
- experimental manipulation
- genetics
- molecular biology
- biochemistry
- ohylogenetic comparisons
What is development? (super basic definition)
Change in phenotype over time
What determines phenotype? (super basic answer)
Gene activity
Name the 4 steps of the gene centered approach
- Identify all genes
- Determine what activites (i.e. functions) each gene has
- figure out when and where each gene is active
- figure out how the activites of each gene are regulated
Draw a basic diagram of the C. elegans life cycle
Draw basic diagram of C. elegans hermaphrodite form
Draw basic diagram of C. elegans male
Name the physical differences between the c. elegans genders (7 for both)
Females have:
- Two-armed gonad
- Vulva
- Spermatheca
- Anus
- Intestine
- Oocyte
- Whip
Males have:
- One-armed gonad
- Sperm
- Vas deferens
- Cloaca
- Fan
- Ray
- spicules
Describe the difference in reproductive capabiltiy between the C. elegans genders
- The Hermaphrodite is Self-fertile: Germ line makes sperm and oocytes
- Male is Cross-fertile: only makes sperm
name the 5 basic behaviors of C. elegans
- Locomotion
- Feeding
- mating
- defecation
- egg laying
Name the 4 basic senses of C. elegans
- Smell
- Taste
- Sense touch
- Thermosensation
Why is meant by the phrase “C. elegans development is essentially invariant”? why is this helpful?
It means that the cells in hermaphroditic C. elegans individuals are produced in an indential pattern of cell divisions between individuals.
This invariant cell lineage makes is possivle to identify all of the cells in an individual and compare them across organisms.
