🌱🌼What is a plant?🌴🍀

What makes a plants?

• autotrophs, make their own food
• Eukaryotes, have a nucleus
• Have a cell wall

Plant adaptations for the land

• Obtaining Water and Other Nutrients
• Retaining Water
• Support
• Transporting Materials
• These are some examples of adaptations

Nonvascular plants

• Some examples are liverworts, mosses, and hornworts
• These are the major groups
• low-growing plants live in moist areas
• they absorb water and other nutrients directly from their environment

Mosses

• The most diverse group
• Have over 10,000 species
• Grow in damp,shady places
• Thin-rootlike structures called Rhizoids
• Rhizoids anchors a plant and gives nutrients

Liverworts

• There are more than 8,000 species of liverworts
• Liverworts have sporophytes that are too small to see
• Wort is an old English word for “plant"
• grow like a thick crust on moist rocks or soil along the sides of a stream
• Named for it's gametophyte, which looks like a human liver.

Hornworts

• There are fewer than 100 species of hornworts
• Unlike mosses or liverworts, hornworts are seldom found on rocks or tree trunks
• Hornworts live in moist soil mixed with grass plants
• The sporophytes are these hornlike structures
• Hornworts are named for the slender, curved structures

Seedless vascular plants

• Ferns, club mosses, and horsetails are the only seedless vascular plants
• Seedless vascular plants have true vascular tissue, and they do not produce seeds
• Instead, they reproduce by releasing spores.

Ferns

• More than 12,000 species of ferns
• Ferns have true stems, roots, and leaves

Horsetails

• Very few species on earth today
• The stems resemble hosretails
• Has a substance called silica which is also in sand

Club mosses

• Be a few hundred species on earth today
• Have a similar life cycle to ferns
• Sometimes called ground pine or princess pine

What is a seed plant?

• Have true vascular tissue
• Use seeds and pollen to reproduce
• All have stems, roots, and leaves

Vascular tissue: phloem/ xylem

• Phloem carries food from the leaves to the roots
• Xylem carries water from the roots to the leaves
• It supports the plant to stay up right.

Pollen and seeds

• A seed is a structure that contains a young plant inside a protective covering
• pollen tiny structures that contain the cells that will later become sperm cells
• By pollen ands seed are seed plants reproduced

Seeds

• Seeds protect the young plant from drying out
• Seeds are used to reproduce by dispersal
• There are many ways of dispersal

Seed dispersal

• Dispersal by water
• Dispersal by air
• Dispersal by animal

Germination

• Germination occurs when the embryo begins to grow again and pushes out of the seed
• Germination begins when the seed absorbs water from it surroundings
• Then the embryo uses its stored food to begin to grow
• Then the embryo’s roots first grow downward; then its stem and leaves grow upward
• A seed that is dispersed far from its parent plant has a better chance of survival

Roots

• Roots anchor a plant in the ground
• Roots absorb water and minerals from the soil
• Roots also sometimes store food
• root cap protects the root from injury from rocks as the root grows through the soil
• two main types of root systems are fibrous roots and taproot system

Stems

• The stem carries substances between the plant’s roots and leaves
• The stem also provides support for the plant
• holds up the leaves so they are exposed to the sun
• Stems can be either herbaceous or woody

Leaves

• Leaves capture the sun’s energy
• Leaves carry out the food-making process of photosynthesis
• Transpiration is the process by which water evaporates from a plant’s leaves

Gymnosperm

• Every gymnosperm produces naked seeds
• many gymnosperms have needle-like or scalelike leaves, and deep-growing root systems
• There are four main types of gymnosperms
• Conifers, Cycads, Ginkgoes, Gnetophytes are the types

Example of gymnosperms

• Some examples of Are Gnetophytes, cycads, ginkgoes, and conifers
• 175 million years ago, the majority of plants were cycads
• Conifers are the largest and most diverse group of gymno sperms today
• only one species of ginkgo today

Anigosperm

• First, they produce flowers
• Second, in contrast to gymnosperms, which produce uncovered seeds
• angiosperms produce seeds that are enclosed in fruits

Examples of angiosperms

• Angiosperms are divided into two major groups: monocots and dicots
• Monocots: Grasses, including corn, wheat, and rice
• Dicots include plants such as roses and violets

Monocot vs dicot

• Dicots include plants such as roses and violets
• Monocot: Grasses, including corn, wheat, and rice
• Dicot stems usually have bundles of vascular tissue arranged in a ring
• vascular tissue in monocot stems are usually scattered ran domly throughout the stem

Plant tropisms:light

• All plants exhibit a response to light called phototro- pism
• The leaves, stems, and flowers of plants grow toward light
• By growing towards the light, a plant receives more energy for photosynthesis

Plant tropism: touch

• plants, such as bladderworts, show a response to touch called thigmotropism
• The prefix thigmo- comes from a Greek word that means “touch"
• As vines grow, they coil around any object that they touch

Plant tropism: gravity

• This response is called gravitropism
• Roots show positive gravitropism they grow downward
• Stems, on the other hand, show negative gravitropism they grow upward