Organisation of living things - Mod 2

Colonial organism

Made up of many single celled organisms working together

Dermal Tissue

Found on the outer layers of the stems, roots and leaves, protects the plant tissues.

Differentiation

The process a cell goes through to become a specialised cell. This generally occurs as a cell matures.

Epithelial Tissue

Is a tissue that covers body surfaces, protects organs and forms glands. Cells are densely packed and occur in sheets or layers.

Ground Tissue

Found in plants, makes up the internal cells of a plant other than vascular tissue.

Guard cells

Cells that surround stomates, that control their opening and closing.

Meristematic tissue

Found at the tips of roots and shoots, is the site of cell division to produce new growth in plants.

Multicellular organisms

An organism made of many different cells. Are usually eukaryotes (cells have organelles bound by a membrane).

Phloem

A tube in plants (part of vascular tissue) that transports products of photosynthesis (sugars) in a two way direction.

Specialised cells

Perform a specific function. These always form from stem cells.

Stem cells

Cells that do not have a "job" yet. Can come from embryos, brain or bone marrow

Stoma

Pores in leaves that allow for the exchange of gases. Opening (daytime) and closing (night time) of the stomate is controlled by photosyntheiszing guard cells.

Transpiration

The evaporative loss of water from a plant.

Unicellular organism

An organism made of one cell. Eg, bacteria. Are mostly prokaryotes (cells do not have membrane bound organelles eg, a nucleus) and some eukaryotes (cells do have organelles bound by a membrane eg, a nucleus).

Vascular tissue

The tissue in plant that is organised into vessels to transport substances, such as sugar and water. Eg, xylem and phloem in plants.

Xylem

A tube in plants (part of vascular tissue) that transports water in a one way direction (upwards from roots to leaves).

tissue level

groups of similar cells that have a common function

Organ

A collection of tissues that carry out a specialized function of the body

organ system

group of organs that work together to perform a specific function

meristematic tissue

plant tissue found only in the tips of shoots and roots; responsible for plant growth

Volvox

colonial green algae

Amoeba

a kind of single-celled organism in kingdom Protista able to move by itself

vascular tissue

Plant tissue consisting of cells joined into tubes that transport water and nutrients throughout the plant body.

root

An organ in vascular plants that anchors the plant and enables it to absorb water and minerals from the soil.

stem

supporting structure that connects roots and leaves and carries water and nutrients between them

leaf

The major sites of photosynthesis in most plants.

artery

A blood vessel that carries blood away from the heart

vein

A blood vessel that carries blood back to the heart.

Open transport system

System without vessels and haemolymph instead of blood.

closed transport system

A type of circulatory system in which the transport fluid (blood) is always enclosed within blood vessels and pumped consistently by the heat.

Alveoli

tiny sacs of lung tissue specialized for the movement of gases between air and blood

mucus

a slimy substance produced in the nose and throat to moisten and protect them

Platelets

tiny blood cells that help your body form clots to stop bleeding.

Haemoglobin

The protein that carries oxygen in the red blood cells.

Bolus

A term used to describe food after it has been chewed and mixed with saliva

Chyme

Partially digested, semi - liquid food mixed with digestive enzymes and acids in the stomach.

villi and microvilli

increase surface area for absorption

small intestine

Absorbs most nutrients; Main absorption organ of the digestive tract

large intestine

Reabsorbs water and stores and eliminates undigested food

saliva

The fluid released when the mouth waters that plays an important role in both mechanical and chemical digestion

mechanical digestion

Physical breakdown of large pieces of food into smaller pieces

chemical digestion

Process by which enzymes break down food into small molecules that the body can use

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

transpiration-cohesion-tension

Theoretical basis for water movement in plants: evaporation of water from cells within leaves (transpiration) causes an increase in surface tension, pulling water up through the xylem. Cohesion of water occurs because of hydrogen bonding.

Translocation

the movement of materials from leaves to other tissues throughout the plant.

Transpiration

Evaporation of water from the leaves of a plant

source to sink theory

The contents of the phloem tubes flow from the sources to these sinks, where the sugar molecules are taken out of the phloem by active transport.

Trachea

Allows air to pass to and from lungs

vascular bundle

plant stem structure that contains xylem and phloem tissue

Autotroph

An organism that makes its own food

Heterotroph

organism that obtains energy from the foods it consumes; also called a consumer