AP Biology Unit 10 Part 3 - Plants Response to Stimuli and Plant Reproduction

*recommended to go in order*

signal

something that causes a response

reception, transduction, response

what are the 3 stages of the signal transduction pathway?

reception

a signal binds to a receptor

transduction

the signal is relayed through the cell/body

response

activation of cellular responses

tropism

when a plant curves toward or away from a stimulus

phototropism

when a plant shoot grows toward a light source and the cells on the dark side elongate

gravity, wind, drought, floods, salt, heat, cold

what are some Stimuli other than light? Hint: there are 7

gravity

stimuli that makes plants grow up toward the sun

wind

the stimuli that forces plants to grow away from these areas

drought

the stimuli that forces plants to conserve water in these conditions

floods

the stimuli that forces plant roots to undergo apoptosis so that they do not gain too much water

salt

the stimuli that forces plants to absorb less water

heat

the stimuli that forces the stomata to close

cold

the stimuli that forces plants to increase lipid concentration in cell membranes

herbivores

fill in the blank:

• plants defend against ___ by producing thorns, chemicals, and distasteful or toxic compounds

pathogens

fill in the blank:

• plants defend themselves from ___ by having thick cell walls and developing genetic resistance

flowers

specialized structures for sexual reproduction

sepals

modified green petals that enclose the flower before it opens

petals

brightly colored and attract pollinators 

Stamens

male reproductive organs that produce pollen (male gametophytes)

pollen

the sperm of flowers

filament

the stalk of the stamen

anther

the top of the filament where meiosis occurs to make pollen

carpels

also known as pistils; female reproductive organ of flowers and produce ovules

ovules

eggs of flowers

ovary

base of the carpel that contains ovules

style

the stalk of the carpel that pollen travels down

stigma

the sticky top of the carpel that receives pollen

fruits

mature, ripened ovaries (after pollination has occurred)

• fleshy or dry

• disperse seeds

wind, water, animals

what three things spread/disperse seeds (NOT pollen)

angiosperm life cycle

• eggs + sperm = fertilization making a zygote

• zygote becomes an embryo then a seed

• seed is planted and becomes a flower

• flowers produce eggs and sperm via meiosis

monoicous

plants have both male and female flowers on the same plant

dioicous

plants have male flowers on one plant and female flowers on a different plant.

bisexual

plants have flowers with both male and female parts on the same flower (Perfect/Complete)

how plants prevent self-fertilization

• separate male and female parts

• male and female parts mature at different times

• plants reject their own pollen (some)

embryo

the ___ goes through mitosis to form a seed

• the seed has a coat, an endosperm (food), cotyledons (baby leaves), shoots, and roots

simple, aggregate, multiple

what are the 3 fruit types

simple

develop from a single carpel of one flower (pea pod)

aggregate

develops from many carpels of one flower (raspberries)

multiple

develops from many carpels of many flowers (pineapple)

seed germination

Seeds remain dormant until conditions are right for ___

• The first organ to emerge is the root (from the radicle)

• Next the shoot breaks through the soil surface

imbibition

when germination starts with water uptake

fragmentation

is the separation of a parent plant into parts that develop into new plants (plant clones)

grafting

is attaching the stem of one plant to the roots of another (lemon/lime tree)