Module 2 - Organisation of living things

unicellular organism

An organism made up of one cell.

colonial organism

collection of identical cells that live together in a connected group

multi-cellular organism

An organism that consists of more than one cell.

volvox

Colonial green algae held together in a secretion of gelatinous material, resembling hollow ball

cyanobacteria

single celled photosynthetic bacteria

hierarchical structure of organisation

cells --> tissue --> organ --> organ system --> organism

cell specialisation and differentiation

When a stem cell turns into another sort of cell to do a certain job (such as a muscle cell).

specialised cell

A cell that is adapted for a certain specific function (job).

tissue

A group of similar cells that perform the same function.

connective tissue

Tissue that functions mainly to bind and support other tissues.

epithelial tissue

A body tissue that covers the surfaces of the body, inside and out

muscle tissue

A body tissue that contracts or shortens, making body parts move.

vascular tissue

specialized tissue in plants that carries water and nutrients

the leaf

organ that produces sugar for a plant

the heart

organ that helps pump blood around the body

organ

group of tissues that work together to perform closely related functions

organ system

A group of organs that work together in performing vital body functions.

organism

a living thing

gas exchange

the process of obtaining oxygen from the environment and releasing carbon dioxide

oxygen

A gas that is brought into the body by the respiratory system.

carbon dioxide

A gas that is expelled from the body by the respiratory system.

photosynthesis

Conversion of light energy from the sun into chemical energy.

cellular respiration

the process by which cells use oxygen to produce energy from food

Mammalian respiratory system

contains lungs, which contain alveoli

Insect respiratory system

contain spiracles and tracheae

Fish respiratory system

contains gills

Lungs

Main organs of the respiratory system

Alveoli

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

Digestive system

Breaks down food into absorbable units that enter the blood for distribution to body cells.

physical digestion

The mechanical breakdown of large food particles into smaller ones

chemical digestion

Enzymes break down food into smaller molecules

amino acids

building blocks of proteins

absorption

The process by which nutrient molecules pass through the wall of the digestive system into the blood

small intestine and large intestine

stomach

large muscular sac that continues the mechanical and chemical digestion of food

teeth

structure of the digestive system that begins mechanical digestion

small intestine

Digestive organ where most chemical digestion and absorption of food takes place

large intestine

Absorbs water and forms feces

pancrease

a large gland behind the stomach that secretes digestive enzymes into the duodenum

liver

organ that produces bile and stores nutrients

villi

tiny, finger-like structures that protrude from the wall of the intestine

microvilli

projections that increase the cell's surface area for maximum absorption of nutrients

rectum

The last part of the digestive tract, through which feces are eliminated

roots

Absorbs water and minerals from the ground. Anchors plant in ground.

root hair

small hairs on a root that produce a large surface area through which water and minerals can enter

osmosis

movement of water from an area of low solute to an area of high solute through a semi-permeable membrane

diffusion

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

stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move

guard cells

control the opening and closing of stomata

spongy mesophyll

Loose tissue beneath the palisade layer of a leaf; has many air spaces between its cells

epidermis

protective layer of a leaf

cuticle

the waxy, waterproof layer that covers the leaves and stems of most plants

palisade mesophyll

layer of closely packed mesophyll cells under the epidermis that absorb light that enters the leaf

Whole blood

Connective tissue made of plasma, red blood cells, white blood cells, and platelets.

red blood cells

Blood cells that carry oxygen from the lungs to the body cells.

plateletes

cell fragments that help blood to clot after an injury.

white blood cells

diease fighting cells in blood

plasma

liquid portion of blood

hemolymph

In invertebrates with an open circulatory system, the body fluid that bathes tissues.

open circulatory system

system in which blood is not always contained within a network of blood vessels

closed circulatory system

A circulatory system in which the oxygen-carrying blood cells never leave the blood vessels

Aorta

the main artery of the body, supplying oxygenated blood to the circulatory system

Pulmonary artery

Carries deoxygentated blood from the heart to the lungs

Atrium

A heart chamber that receives blood.

Ventricle

Pumps blood out of the heart

valves

prevent back flow of blood

blood vessel

a tubular structure carrying blood through the tissues and organs; a vein, artery, or capillary.

capillaries

Microscopic vessel through which exchanges take place between the blood and cells of the body

veins

blood vessels that carry blood back to the heart

arteries

carry blood away from the heart

vascular bundle

plant stem structure that contains xylem and phloem tissue

xylem

transports water and minerals

phloem

Living vascular tissue that carries sugar and organic substances throughout a plant

transpiration cohesion adhesion theory

how water travels in xylem

translocation

how sugar and other organic nutrients travels in phloem