Biology Chapter 4 test

Start 4.1 Multicellularity and cell specialisation

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Major organs of vascular plants

-Roots -Leaves -Stems -Flowers -Fruits

what are the four systems

1) digestive system 2) the breathing system 3) the transport system 4) the reproductive system

Multicellular organism groups

1) specialised cells 2) tissues 3) organs

Organs

A group of different tissues that work together to perform one or more specialised tasks eg the heart pumps blood and the bring oxygen to the body

For efficient gas exchange

A large surface area Efficient removal of gas after exchange e

Advantages and Disadvantages of multicellularity

Advantages: Multicellular organisms... -are more energy efficient -have a longer life span -they can grow larger Disadvantages multicellular organisms.. cannot function independently more energy required for reproduction

Cell Specialisation

Cells have different shapes and structures to carry out different functions we call these specialised cells, cell specialisation allows an organism to function efficiently Specialised cells in plants example root hair cells have the function to absorb water and mineral salts specialised cells in animal cells example muscle cells have the function to control body movement

Cell types

Epidermal cells/ Func protects the inner layer of the cell/ structure thin and leathery

Multicellular

Multicellular organisms are made up of MORE than one cell, they are made up of Eukaryote cells. For an organism to be classed as multicellular they must have the same DNA and the cells must be dependent on each other. An example of a multicellular organism is a cat.

Specialised cells

Multicellular organisms are specialised to have a particular functions some examples of specialised cells are found in humans - nerve cells

Vascular plants have 2 systems

Root systems & Shoot systems

Pholem

Transports the organic products of photosysnthesis from leaves to the rest of the plants

Unicellular vs Multicellular

Unicellular have one cell compared to multicellular the have many Unicellular uses prokaryote and eukaryotes, multicellular only uses Eukaryotes Unicellular are asexual compared to multicellular the have sexual reproduction

Unicellular

Unicellular organisms are made up of one cell, these organisms usually live in water; examples of unicellular organisms can include yeast

Major tissues of the leaf structure

Upper cuticle/Struct: covers the leaf with a waxy covering/Func: reduces water loss Upper epidermis/Struc: No chloroplasts/ Func: reduces water loss Lower epidermis/Struc; contains stomata/func: allows gas exchange

Plants need several substances that include...

Water Sugar Inorganic Nutrients

These materials are transported by vascular tissue

Xylem and Pholem

organsims

all the systems in the body work together to from an organism

Sieve elements

are living cells with thin walls the end walls are perforated and called live plates

Tissues

groups of similar cells that are working together to carry out a particular function eg animals have muscles and bones

Factors effecting the rate transpiration

include... Light Temp Humidity

Transpiration

is the passive movement of water through a plant from the roots

Cell Differentiation

is when unspecialised cells (stem cells) become specialised to perform a specific function. Stem cells are cells that can self renew by cell division

companion cells

maintain the living state of the sieve element cells and are connected to them by means of plasmodesmata

Gas exchange

provides a means of supplying organisms with o2 and removing c02

Translocation

the movement of something form one place to another

What is xylem

xylem Transports water and inorganic nutrients from roots to the rest of the plant