Classification and Diversity of Living Organisms
Concept and Use of a Classificatory System
Binomial System
A system of naming species in which the scientific name of an organism is made up of two parts showing the genus (starting with a capital letter) and species (starting with a lower case letter), written in italics when printed (therefore underlined when handwritten) e.g. Homo sapiens
Classes of Animals
Class Fish
Moist skin, fins, gills, scaly skin, poikilothermic (cold-blooded), lays eggs with jelly coat.
Class Amphibia
Poikilothermic (cold-blooded)
Read MoreHuman Body Systems: Functions and Diseases
Human Body Systems: Functions & Diseases
Apparatus and Their Functions
| Apparatus | Function |
|---|---|
| Digestive | Responsible for digesting food and converting it into simpler substances (nutrients) (digestion). |
| Respiratory | Provides for the exchange of gases, i.e., oxygen intake and carbon dioxide removal. |
| Circulatory | Transports oxygen and substances throughout the body via the blood. |
| Excretory | Removes waste substances carried by the blood. |
Anatomy of the Digestive System
Digestive Tract: Mouth, pharynx, esophagus, stomach,
Read MoreDNA Replication, Transcription, and Translation Explained
DNA Replication, Transcription, and Translation
Understandings:
The replication of DNA is semi-conservative and depends on complementary base pairing.
- Complementary base pairing ensures two identical DNA strands are formed after replication is complete.
- In replication, the original strands are used as templates, allowing complementary bases to be added according to base pairing rules.
- DNA replication is semi-conservative, meaning the new DNA that is created consists of one old strand (template) and one
Competitive and Non-Competitive Enzyme Inhibitors
Competitive Inhibitors
These are structurally similar to the substrate of the enzyme and bind to the active site. This means that when a competitive inhibitor binds to the active site of an enzyme, it prevents the substrate from binding. Only once the inhibitor has been released can the substrate bind. The inhibitor is called a competitive inhibitor as it competes with the substrate for the active site.
The effects of a competitive inhibitor can be reduced by increasing the substrate concentration.
Read MoreHominid Evolution: From Africa to Homo Ergaster
The Hominids: An Evolutionary Overview
The hominids are a group of non-arboreal primates whose origin is in Africa for at least several million years. A key characteristic is moving into a bipedal position. This conditions the situation of the foramen magnum at the base of the skull, through which the spinal cord passes to the backbone. On each side and downward facing are the occipital condyles: the double articulation of the skull to the backbone. Their palate is U-shaped, surrounded with a dental
Read MorePlant Physiology: Relationships and Reproduction
Plant Relationships and Stimuli Responses
Plants can receive and transmit stimuli from the external environment and have the capacity for movement. The regulation of a plant’s physiological activities depends on many internal and external factors. Internal factors are mainly plant hormones or phytohormones, while external factors include the length of day and night.
Plant Hormones
A hormone is a chemical produced by specialized cells, which acts on other cells of the individual, away from the hormone’
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