FINAL - Lecture 13 - Flowers, Fruit, and Seeds

Do both Angio and Gymnosperm have pollen and seeds

yes

Do both Angio and Gymnosperm have Fruit

only angiosperm

Do both Angio and Gymnosperm have Ovules

Yes

Do both Angio and Gymnosperm have Ovaries

ONLY ANGIOSPERM

Gymnosperm do not make fruit because they lack _________

OVARIES

C

Where are seeds

D

What part of the plant is popcorn

endosperm

T/F - Endosperm is only produced by angiosperms

TRUE

Endosperm is produced by the process of ___________

Double Fertilization

Label

Perianth

calyx + corolla

Receptacle

part of flower stalk where parts are attached

Flowers have a combination of __________ and _________whorls

non-reproductive
Reproductive

Flowers are arranged in ______

whorls

non-reproductive whorls

calyx and corolla (( PERIANTH ))

Reproductive Whorls

Stamen and Carpels

Whorls are in a ___________ order

specific order

androecium

all the stamens of a flower

gynoecium

ALL the carpels of a flower

gynoecium types

apocarpous
syncarpous

Monocarpous

apocarpous gynoecium

Free standing carpels

syncarpous gynoecium

fused carpels

Monocarpous gynoecium

singular carpels

Blackberry carpels are _______

apocarpous

Pollen is comprised of ________ cells

2

Parts of pollen and what they do

The tube cell → elongates to produce the pollen tube

The generative nucleus → undergoes mitosis to produce sperm cells.

Pistils can be _________ or ___________

simple
compound

Simple Pistil

ONE CARPEL

TWO or MORE CARPEL

differences between gymno and angiosperm

REVIEW

Angiosperm undergo _________- fertilization

double fert

Explain double fertilization

each pollen grain delivers two sperm cells,
one of which fertilizes the egg to form the zygote,
while the other fuses with the central cell to produce the endosperm

Embryo sac

megagametophyte

Ovule

embryo sac + integuments (+ nucellus)

Placenta

part of the ovary wall where the ovules attach

Flowers can be __________ or __________

perfect or imperfect

perfect flowers

pistils and stamens on same flower

imperfect flower

plant has either pistils OR stamens on a single flower

Types of IMPERFECT FLOWER plants

Monoecious
Dioecious

Monoecious

male and female on the same plant

Dioecious

male flowers and female flowers on different plants

T/F - It is possible to have a monoecious plant
with imperfect flowers

TRUE

Which are monoecious which are dioecious

A is MONO
B is DIOE

A flower develops from a _________ meristem in one set of reproductive, ______, organs

floral
Determinant

what is an inflorescense

An inflorescence develops from an inflorescence meristem that
produces multiple floral meristems, resulting in many flowers on a shoot

Flowers vs. Inflorescences

ADD

Individual flowers are considered determinate organs because their growth stops once they reach a certain size and form. 

However, the way flowers are arranged on the plant's main stem (the inflorescence) can be either determinate or indeterminate

Flowers are regulated by _________- and _______ cues,
like …

External (temp / photoperiod)
Internal

Steps of flower transition

1. The SAM changes shape (becomes flatter and broader),
2. Floral organs are initiated
3. flower parts mature
4. The flower opens

How do flowers arange in the correct order of whorls?

MADS-box genes // ABC model

Whorl 1

forms sepal
A genes

Whorl 2

forms petal
A and B

Whorl 3

forms stamen
B and C genes

Whorl 4

Forms carpel
C Genes

describe whorl arrangement

DONUT ESC

Homeotic genes

genes whose mutation causes homeosis—
the transformation of one body structure or organ into another

Homeobox

conserved DNA sequence found in many eukaryotic genes

found in animals, plants, fungi, and protists

Hox genes

subgroup of homeobox genes found only in animals

act as master regulators that pattern major parts of the
animal body

MADS-box genes

MADS-box genes are a different, conserved family
of transcription factors that do not have a homeobox

n plants, many MADS-box genes are _________; including many floral organ identity genes.

homeotic

C

ABC genes are regulate each other, with A and C using ________

mutual inhibition

Arrangememtn of ABC

B on top middle
A and C on bottom

If A gene expression is missing or reduced…..

C gene expression expands, resulting in more whorls with
overlap of C with B and thus stamens replace petals

If C gene expression is missing or reduced…

A gene expression can expand, resulting in more whorls with
overlap of A and B and thus petals replace stamens.

C

D

C gene can impacts…

whorls and determinency

Just a bunch of whorls of leaves

What happens when all three are mutated, but then you insert ABC into the leaves 

Do you get flowers

No
more leaf whorls (CHECK)

Transcription factors (TFs)

regulatory proteins that control gene expression
by binding specific DNA sequences, usually within the promoter or enhancer regions of target genes

Their binding either activates or represses transcription

ABC genes are regulated by 

Transcription Factors

Are there more genes that impact flowers besides ABC

Yes

D and E

D class proteins

promote ovule identity

E class proteins

key MADS-box transcription factors that act as the "glue" in the floral quartet model

CONNECT ABCD

Can ABCD genes be in different arrangements, but still do their typical organs

yes
Homologs exist

What are Tepals

floral organs that do not show a distinction between sepals and petals

AKA → Sepals and petals look very similar

What causes tepals

A and B full overlap

Expansion expression of B genes affects

morphology

B extends over A causes

tepals

Tepals are common in …

TULIPS

ovary wall typically develops into the fruit wall, AKA ________

pericarp

Parts of the pericarp

Endocarp
mesocarp
Exocarp

pericarp

ovary wall
(usually the term is used with no morphologically distinct
differentiated layers)

Exocarp

outer differentiated layer of the ovary
Usually the skin

Mesocarp

middle differentiated layer of the ovary wall.

Usually the flesh

endocarp

inner differentiated layer of the ovary wall

Usually the area surrounding the seed

label parts of pericarp and locate the seed

hypogynous // superior 

flower has the ovary above the receptacle,

epigynous (inferior).

The flower has an ovary covered by the
receptacle and sitting below the floral organs

Are apples superior or inferior

INFERIOR
the lower portion on the base with brown bits are dead leaves

What are the simple fruits

Drupe
Nut
Berry
Hesperidium
Pome
Samara
Legume
Achene