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Day Date Subject To be read prior to this class period: T 1/13 Setting the stageTh 1/15 Capstone course planning T 1/20 Life Span Cynthia Kenyon’s Lab handoutsTh 1/22 Capstone Topics. Life span discussionT 1/27 Chapter 1Th 1/29 Chapter 3T 2/3 students = gut bacteria and developmentJennifer Ditano, Afaq LamlumTh 2/5 Chapter 2T 2/10 students = hormonal control of sex determinationRaisa Luck, Susan DuongTh 2/12 Chapter 5T 2/17 no class - Winter Break Th 2/19 no class - Winter Break T 2/24 Th 2/26 Chapter 6T 3/3 students = endocrine disruptorsMeg Thurell, Nicole BordeauTh 3/5 T 3/10 Midterm Exam

From the Preface of our textbook:

“Development weaves genotype and environment into phenotype.”

From the Preface of our textbook:

“Development weaves genotype and environment into phenotype.”

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identical twins

schizophrenia

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discordance = when identical twins have different phenotypes

polyphenism = two or more discrete phenotypes from one genotype

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Evidence the following contributes to aging and life span:

1) gene regulation using a polyphenism as a model example

2) normal metabolism “higher metabolism = shorter life span” free radicals repair mechanisms mitochondria

caloric restriction

3) low level stress induction

caloric restriction

4) telomere shortening

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Why are we studying aging as a topic in this course?

1) Life span is based on the rate of aging and although aging has seemed like a physiological ‘wear and tear’, it now seems to be related to growth / reproduction and those are developmental processes.

2) Life span is inherited (there is a program represented in the genetic code – genotype).

3) The life span phenotype is not always constant, but can affected by the environment (phenotypic plasticity).

4) The study of model examples of phenotypic plasticity is helping us understand complex but fundamental principles of development.

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Why are we studying aging as a topic in this course?

1) Life span is based on the rate of aging and although aging has seemed like a physiological ‘wear and tear’, it now seems to be related to growth / reproduction and those are developmental processes.

2) Life span is inherited (there is a program represented in the genetic code – genotype).

3) The life span phenotype is not always constant, but can affected by the environment (phenotypic plasticity).

4) The study of model examples of phenotypic plasticity is helping us understand complex but fundamental principles of development.

POSSIBLE EXAM QUESTION

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Figure 1.15  Predator-induced and typical morphs of genetically identical individuals of Daphnia

Reduced numbers of eggs.transgenerational

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Chapter 3: Co-Development During Symbioses

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POLYPHENISM (?)

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squid with bacteria squid without bacteria

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metazoan / microbe symbioses

How are microbes acquired/transmitted? 1) acquired from the environment 2) horizontal transmission 3) vertical transmission

How are microbes maintained?

How is host development affected?

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Chapter 3: Symbioses

parasitism mutualism commensalism Some of Gilbert’s examples are about environmental

modulation of development and some aren’t.

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Life Cycle Symbioses

pollination

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Plant / fungus symbioses:

Endophytes

Mycorrhizae

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Wolbachia

Bacteria transmitted primarily by being in the cytoplasm of the egg. Therefore, natural selection favor increasing the proportion of females:

1)male lethality = less competition for resources2)males change sex3)“male” parthenogenesis4)cytoplasmic incompatibility

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Organisms often form symbioses not just with one microbial speciesbut with several = microbial consortia.

An oligochaete worm, Olavius algarvensis

No mouth, anus, or gut.Hosts a sulfur-metabolizing bacterium and three other species.

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Mammalian gut development

introduction to gut environment and biofilms

1) bacteria and blood capillary development

2) GALT = Gut Associated Lymphoid Tissue

3) gut bacteria and obesity (probiotics)

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Mammalian gut development

1) bacteria and blood capillary development

2) GALT = Gut Associated Lymphoid Tissue

3) gut bacteria and obesity (probiotics)

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Mammalian gut development

1) bacteria and blood capillary development

2) GALT = Gut Associated Lymphoid Tissue

3) gut bacteria and obesity (probiotics)

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