Genetics, Seedless Plants, Gymnosperms

Female & Male Corn Flowers

males: tall, narrow and pointy; sperm is haploid (1n)

females: long, hair-like strands; egg is haploid (1n); zygote (fertilized egg) is diploid (2n)

Phenotype vs Genotype

pheno: observable traits (ex: corn kernel smooth, wrinkled, purple, yellow)

geno: the set of genes (homozygous dominant: PP; homozygous recessive: pp; heterozygous: Pp)

Corn Documentary

main idea was geneticist believed teosinte plant was an ancestor of modern corn; F2 generation form crossbreeding teosinte and maize proved his hypothesis was correct

Corn Model

1: embryo

2: endosperm: nutritive part for seedling

3: pericarp- outer layer or kernel

4: seed coat- layer between pericarp and aleurone

5: aleurone- inner layer around endosperm

Punnett Squares

practice monohybrid using F1 of SS and ss; find F2 by crossing two offspring from F1 (Ss and Ss); 

practice dihybrid cross- Punnett square that looks at two characteristics: use PPSS and ppss;  use foil method to find genotype for F2 from F1 offspring

look at corn lab for help

Bryophyte Lifecycle

diploid stage: fertilization produces zygote; becomes sporophyte with capsule and seta attached to haploid mature gametophyte

haploid stage: meiosis produces spores; spores germinate; motile sperm from antheridium swim down neck canal of archegonium

rewatch lifecycles from week 12 lecture

Polytrichum Capsule

black: epidermis (outermost layer)

red: columella

blue: spores

green: photosynthetic tissue is out of FOV but is above the seta near the bulge-y part

diploid

Marchantia Sporophyte

Lunularia (Liverwort)

thallus is fleshy green area

rhizoids are delicate root-hair-like structure that function in anchorage and absorption

moon-shaped cups that contain gemmae

gemma is a small outgrowth of tissue that becomes detached from the parent body and is capable of developing into a complete new plant or other organism

Gemmae Cup Dissection

Selanginella Stem

Strobilus (Lycophyte Cone)

sporangium: contain spores; the darker green splotches

sporophyll: sporangium-bearing modified leaf

Bryophyte Antheridia and Archegonia

Gymnosperm Overview

produce seeds that are “naked” i.e. not protected by fruit

woody trees, shrubs, or lianas (woody vines)

members: conifers, gnetophytes, cycads, and gingko

Pine Ovulate (Female) Cone 1 Year

label/define megasporocyte, ovule, ovuliferous scale

Ovulate Cone Dissection Scope

blue: cone axis

red: ovuliferous scale

black: ovule

Cones at Different Years

Pine Staminate (Male) Cone

label/define microsporangium and microspores

what do microsporangia develop into?

microsporangia develop into pollen grains

Pine Lifecycle

Pollen Grains

haploid

Zamia Ovule

green: megasporangium; yellow: archegonia; blue: egg; pinkish: integument; orange: micropyle (check atlas for better pic of last two)

Ginkgo Catkins & Fruit

identify female gametophyte, embryo, seed coat

Dissected Gingko Fruit

Parts of Ginkgo Fruit

Cycads

from one of those plants that look like palm trees but aren’t

Juniper Berries