Biology 14

Phytochromes

A class of light receptors in plants. Mostly absorbing red light, these photo receptors regulate many plant responses, including seed germination and shade avoidance.

Incomplete flower

A flower in which one or more of the four basic floral organs such as sepals, petals, stamens, or carpels are either absent or nonfunctional.

A complete flower

A flower that has all four basic floral organs: sepals, petals, stamens, and carpels.

Complete flower

A flower that has all four basic floral organs: sepals, petals, stamens, and carpels.

vegetative reproduction

A form of asexual reproduction in which offspring grow from a part of a parent plant

Tropism

A growth response of a plant toward or away from a stimulus

Gravitropism

A growth response to gravity

Phototropism

A growth response to light

Thigmotropism

A growth response to touch

The chemical that Went discovered is?

A hormone

Double fertilization

A mechanism of fertilization in angiosperms, in which two sperm cells unite with two cells in the embryo sac to form the zygote and endosperm.

Dormancy

A period when an organism's growth or activity stops

Photoperiodism

A plant's response to seasonal changes in length of night and day

transpiration-cohesion theory

A possible explanation for water movement in a plant; as water is released from the leaves, additional water molecules must enter the roots

Micropyle

A small gap between the integuments that forms an opening into the ovule.

Nectar

A sweet fluid secreted at the bases of the petals

Pollen tube

A tube that forms after germination of the pollen grain and that functions in the delivery of sperm to the ovule.

Hormone

Any chemical produced by on e area of an organisms and transported to another part where it causes a response.

Cohesion

Attraction between molecules of the same substance

Tissue culturing

Can produce hundreds of genetically identical plants

Fritz W. Went

Discovered the chemical auxin that caused elongation in plants.

Active transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

Transpiration

Evaporation of water from the leaves of a plant

Composite flower

Flower that is made of many, tiny flowers

Photosynthesis

For each molecule of glucose made by plants, six or more molecules of water must be broken down into hydrogen ions and electrons, which are necessary for photosynthesis.

All of the following factors help move water up a plant except?

Hydrolysis

Abscisic acid

Inhibits cell growth, helps close stomata

Integuments

Layers of sporophyte tissues that contribute to the structure of an ovule of a seed plant.

Sepals

Leaflike parts that cover and protect the flower bud

Thigmonastic movements

Nastic movements that occur in response to touching a plant

Proper oxygen

Oxygen is necessary for normal cellular respiration. The embryonic plant also needs oxygen to use the food stored in the endosperm and cotyledons.

What are the accessory flower parts?

Pedicel Receptacle Sepals Petals

What are the 6 basic flower parts?

Pedicel, Receptacle, Sepals, Petals, Stamen, and Carpel.

Plants use water for what several purposes?

Photosynthesis Turgor Pressure Hydrolysis Circulation

Phytochromes are

Pigments that control a plant's response to light and dark

Auxins

Plant hormones that lead to phototropism by elongating the dark side of the plant

Hydrolysis

Plants often break large organic molecules apart by combining them with water molecules. Complex organic molecules can be broken into simple monomers by hydrolysis reactions.

Short-day plants

Plants that flower when the period of light is less than 12 hours

Long-day plants

Plants that flower when the period of light is longer than 12 hours

Insectivorous plants

Plants that have leaves designed to catch and digest insects.

Day-neutral plants

Plants whose flowering cycle is not sensitive to periods of light and dark

Ethylene

Produced by fruit and stimulates ripening.

What are the 3 requirements for a seed to germinate?

Proper moisture, temperature, oxygen

Endosperm

Provides food for the embryonic plant while in the seed and when first sprouting.

Nyctinastic movements

Responses to the daily cycle of light and dark

Proper moisture

Seeds need moisture to initiate the germination process.

Proper temperature

Seeds require certain temperatures for the germination process to begin.

Budding

Similar to grafting, but rather than using a stem, a bud with a sliver of bark is places under a slit in the bark of the stock.

Pedicel

Stalk that supports the flower

Totipotent

Stem cells with the potential to differentiate into any type of cell.

Cytokinins

Stimulate cell division in plants and promote lateral bud growth.

Gibberellins

Stimulates both cell division and cell elongation in leaves and stems.

Turgor Pressure

The abundant presence of water in the cells stiffens the herbaceous parts of plants. The water is is contained in the central vacuole of the plant cell. As the central vacuole fills with water, it exerts outward pressure against the rigid cell wall.

Germination

The beginning of the growth of an embryonic plant within a seed

Heliotropism

The directional growth of a plant in response to sunlight

Guttation

The exudation of water droplets, caused by root pressure in certain plants.

Carpel

The female reproductive organ of a flower, consisting of the stigma, style, and ovary.

carpel

The female reproductive organ of a flower, consisting of the stigma, style, and ovary.

Sap

The fluid carried in xylem and phloem vessels

Stamen

The male reproductive organ of a flower

Translocation

The movement of carbohydrates throughout the plant.

Circulation

The organic molecules and minerals that a plant needs for metabolism and growth must be dissolved in water to be moved form one area of the plant to another.

Plantlets

The parent plant forms small complete plants on special stems or leaves that can grow independently.

hypocotyl

The part of a plant embryo directly below the cotyledons, forming a connection with the radicle.

Critical dark period

The period of uninterrupted darkness that is required for a plant to flower

Turgor pressure

The presence of water inside a plant cell in sufficient quantity to give the cell stiffness.

Grafting

The process in which a stem, called the scion, is cut off from one plant and placed in contact with the stem of a rooted plant called the stock.

Pollination

The process whereby pollen is transferred from the anther to the stigma.

Nastic movements

The result of the loss or gain of turgor pressure in certain cells.

If a plant is grown in an overferttilized area, what will most likely happen?

The roots will die as the cells undergo plasmolysis.

Style

The stalk of a flower's carpel, with the ovary at the base and the stigma at the top.

Layering

The stem of a parent plant is usually bent over and buried in moist soil

Root pressure

The upward push of water within the style of vascular plants, caused by active pumping of minerals into the xylem by root cells

What is true of plant hormones?

They regulate the growth of plants. They include auxins, cytokinins, and abscisic acid, They are chemicals produced in one area of the plant and transported to another area. They control a plant's response to environmental conditions.

A package of plant fertilizer contains the numbers 10-20-15. What do these numbers mean?

They show the percentages of nitrogen,phosphorus, and potassium in the fertilizer.

The release of water through the stomata of a leaf is called

Transpiration

Stem cutting

Usually a section of a stem that is placed in water or in moist sand, soil, or similar medium.

Examples of insectivorous plants

Venus flytrap, sundew, butterwort, pitcher plants, bladderwort

Sources

Where carbohydrates are stored or manufactured.

Sinks

Where carbohydrates are used or stored.

Leaf cutting

a cutting made from a leaf without a petiole

Which is most likely to inhibit the flow of water through a plant?

a decrease in the concentration of minerals in the soil

Etiolated

a plant that does not receive adequate light

Plants absorb minerals by?

active transport

The sac that bears the pollen grains is the

anther

Vegetative reproduction cultivates plants that

are clones of the parent

Petals

are just the inside of the sepals

5 major groups of hormones

auxins, gibberellins, cytokinins, ethylene, and abscisic acid.

Phosphorous

dark green to purplish leaves; stunted growth Functions: formation of ATP, nucleic acids, some fats, coenzymes

What plants will flower even when the critical dark period is interrupted?

day-neutral

Magnesium

death of leaves from the stem up Functions: chlorophyll, needed for some enzyme actions

Epycotyl

develops into first leaf

Calcium

disintegration of young shoots and root tips Functions: cell walls, aids in regulation of the uptake of other elements

Radicle

embryonic root

3 parts of a seed

embyronic plant, stored food, and a seed coat

This hormone is used by fruit growers to quickly ripen fruit for sale.

ethylene

A plant that does not receive adequate light and becomes pale, long, and spindly is said to be

etiolated

T/F Insectivorous plants eat insects in order to obtain energy.

false

Which of the following methods will help replenish minerals in the soil?

fertilizer crop rotation mulch

A mature ovary is called a?

fruit

Iron

gradual yellowing of leaves between small veins, then between larger veins Functions: chlorophyll formation, part of many enzymes

In this process, a stem from one plant is attached to the stem of another plant, and they are allowed to grow together.

grafting

Many botanists refer to plant hormone as ?

growth regulators

Nitrogen

light green to yellowish lower leaves; little growth Functions: production of amino acids, proteins, nucleic acids, chlorophyll, coenzymes

Pressure-flow model

model for predicting how sugars are transported from photosynthetic tissue to the rest of a plant

The opening and closing of the morning glory and the rapid closure of a venus flytrap leaf are example of ?

nastic movements

The growth of roots into the soil is an example of

negative phototropism

The stalk that supports the flower is the

pedicel

Chemotropism

plant growth in response to a chemical

Halophytes

plants that live in highly saline (salty) soil

Once a pollen grain lands on the stigma, a(n)__________ is produced that grows down the style and into the ovary.

pollen tube

Which is not necessary for most seeds to germinate?

proper amount of light

Hydrotopism

response to water

Natural vegetative reproduction

sometimes results because a portion of a plant forms the structures to make another complete plant.

The female reproductive structures are the

stigma, style , and ovary

Another name for a seed coat is?

testa

Capillarity

the attraction between molecules that results in the rise of a liquid in small tubes

Receptacle

the enlarged end of the pedicel that bears the remainder of the flower parts

Anther

the part of a stamen that contains the pollen.

A growth response to touch is called a

thigmotropism

Using special culturing media, scientists can force totipotent cell to differentiate into all the tissues needed for an entire plant. What is this process called?

tissue culturing

The movement of sugars through a plant is called?

translocation

What factors help move water up a plant?

transpiration root pressure cohesion

T/F A period of inactivity in plants is called dormancy.

true

T/F Farmers sometimes use vegetative reproduction to produce plants that mature sooner than seedlings.

true

T/F Hydrotropism is not actually a tropism.

true

T/F Plants need water for photosynthesis, hydrolysis, and circulation.

true

T/F Seeds consist of an embryonic plant, stored food, and a seed coat.

true

T/F White potatoes can reproduce vegetatively by underground stems.

true

The presence of water inside a cell that gives cell the stiffness is?

turgor pressure

Stigma

uppermost tip of the carpel, when mature has a sticky substance on it to receive the pollen

Permanent wilting

when a plant wilts, but cannot recover when placed in a saturated atmosphere

Hilum

where the seed was attached to the ovary wall

Sulfur

yellowing of young leaves Functions: some proteins, amino acids, coezymes

Potassium

yellowish leaves, turning brown at the margin; weak stems Functions: protein synthesis, cell membranes, nucleic acids