biology baseline test

what is the lineas system

all living things are divided into kingdoms, phylum, class, order, family, genus, species

• memnomic device- King Philip Came Over For Good Soup

what is the binomial system

• gives organisms a name used world wide

• first part is their genus and the second part is their species

what is the three domain system

Carl Woese added three large groups called domains above kingdoms

- As evidence of internal structures became more developed due to improvements in microscopes, and the understanding of biochemical processes progressed, new models of classification were proposed.

• archaea- primitive bacteria which live in extreme environments such as hot springs

• bacteria- ture bactera(despite having similar features to archaea)

• Eukaryota- organisms who have a nucleus enclosed in membranes, includes the kingdoms protists, fungi, plants and animals

what are evolutionary trees

used to show how closely related organisms are. To complete this they use classification data and fossils for extinct species.

what do newer systems of classification look at

• DNA- how similar and different the base sequence is

• other molecules- eg proteins and enzymes

• early development- how they grow from an embyro to a baby

how are organisms placed into groups

• depending on theie similarities/ differences

• placed in groups in classification hierarchies

define species

a species is a group of organisms that look similar and can produce to give fertile offspring (their childeren can also reproduce)

name all the components of the breathing system

• trachea - windpipe

• intercostal muscles- which contract and relax to ventilate the lungs

• bronchi- air moves from trachea to here

• bronchioles - air moves from bronchi to here

• alveoli - air sacs where gas exhange occurs

• diaphragm - seperates lungs from digestive organs, moves down causing inhalation

how are the alveoli adapted for gas exchange

• the walls of the alveoli consist of a single layer of thin, flattened, epithelial cells. Diffusion happened faster when molectules only have to travel short distances- SHORT DIFFUSION PATHWAY

• diffusion is faster when there is a bigger difference in concentration between two regions. The large blood supply flowing through the rich network of capillaries round alveoli carries away the O2 that has diffused through the alveolar walls. This ensures theres a higher concentration of O2 inside the alveoli than in the blood- reverse is true for C02- HIGH CONCENTRATION GRADIENT- LARGE BLOOD SUPPLY

• the alveolar walla are fully permeable to dissolved gases. O2 and CO2 can pass easily through the cell membranes of the epithelial cells.

• they are very small and arranged in clusters, creating a large surface area for diffusion to take place

describe the double circulatory system