Sin título

Página 1

ECOSYSTEMS-

ABIOTIC AND BIOTIC FACTORS-

ABIOTIC FACTORS: a non-living component of an ecosystem. (e.g air quality and humidity, the amount of sunlight)

WATER: solvent for all materials in cells; provides buoyancy (uplift and support).

TEMPERATURE: measure of how hot or cold a substance is, affects speed of chemical reactions.

FIRE: hot substance that can consume. Can kill some plants, and help others.

LIGHT: form of energy called electromagnetic radiation, necessary for photosynthesis. Affects growth of plants, animals etc.

SOIL TYPE: different types of soil due to nutrients level, provides plants with water and minerals.

OXYGEN: amount of oxygen in water, needed by all living organisms to survive.

BIOTIC FACTORS: a living thing that interacts with other parts of its ecosystem. (e.g leaves, rotting logs, faeces and urine)

COMPETITION: relationship between organisms that are trying to use the same limited resource.(e.g cheetah’s competing over a gazelle)

PREDATION: relationship where one organism kills and eats the other organism. (e.g praying mantis eats grasshopper)

MUTUALISM: relationship between two species where both gain something. (e.g cleaner shrimp and fish)

COMMENSALISM: relationship where one organism is benefited and the other is unaffected. (e.g barnacles attached to whale)

PARASITISM: relationship where one organism lives on or in another organism and feeds off it. (e.g zombie parasite on ant)

FOOD WEBS / CHAINS-

PRODUCERS: an organism that makes its own food through photosynthesis.

CONSUMER: an organism in a food chain that feeds on other organisms.

DECOMPOSER: break down dead bodies and wastes, and recycle matter for the producers to reuse. (e.g bacteria and fungi)

FOOD CHAIN: diagram showing the sequence of organisms feeding on each other.

FOOD WEB: All the connected food chains in an ecosystem.

An energy pyramid showing the relative amount of energy available at each level of a single food chain.

PHOTOSYNTHESIS-

Sunlight

carbon dioxide + water -------------> glucose + oxygen

ADAPTATION-

-Changes in abiotic factors change biotic factors. (e.g warmer weather = plants flowering, birds immigrating)

ADAPTATION: any feature that assists an organism to survive and reproduce in its environment biodiversity: the range of different species

STRUCTURAL: specialised body part (e.g size, shape, colour)

FUNCTIONAL: the way an organism's body works (the organism can’t control it)

BEHAVIOURAL: a habit or action (e.g bats emitting clicking sounds)

HUMAN IMPACTS ON ECOSYSTEMS-

HABITAT DESTRUCTION: damage caused to the factors in the environment needed for survival

CHEMICAL POLLUTION: chemicals escaping into the environment that can damage ecosystems

OVERCROPPING: removing more individuals from a population than can be replaced by breeding

HUMAN BODY-

NERVOUS SYSTEM-

NERVOUS SYSTEM: a communication network that controls all the other systems of your body

CENTRAL NERVOUS SYSTEM (CNS): receives information from all over the body, processes that information, and then sends out messages telling the body how to respond. (made up of the spinal cord and brain)

PERIPHERAL NERVOUS SYSTEM: nerves that carry messages to and from the CNS and other parts of your body.

TYPES OF NEURONS-

NEURONS: specialised cells of the nervous system, transmit electrical messages around your body.

MOTOR: carry messages from CNS to effectors.

EFFECTORS: glands that translate messages into actions (part of body moving)

SENSORY: specialised receptors that are sensitive to stimuli; carry messages to brain/ spinal cord from cells in the sense organs. (e.g eyes, skin, ears)

CONNECTOR: transmits messages between neurons in the CNS.

THE BRAIN-

CEREBRUM: controls your conscious thought and voluntary movement.

CEREBELLUM: responsible for coordination and balance

MEDULLA: lower part of brain stem; controls vital functions such as breathing or heart rate.

ENDOCRINE SYSTEM-

ENDOCRINE SYSTEM: body system that controls the internal environment of the body (e.g body temp). Made up of endocrine glands

ENDOCRINE GLANDS: glands that produce hormones and secrete them directly into the blood

HORMONES: chemical substances that act as messengers in the body.

HOMEOSTASIS-

HOMEOSTASIS: the process of maintaining a constant internal environment.

WAVES-

TYPES OF WAVES-

TRANSVERSE WAVES: particles vibrate at right angles to the direction of the wave. (e.g beach- water moves up and down while energy moves forwards)

LONGITUDINAL WAVES: particles vibrate back and forth in the same direction as the wave.

WAVE EQUATION-

v= velocity (m/s)

f= frequency of wave (Hz) 八= wavelength (m)

PERIOD: time it takes for one complete cycle → unit seconds

WAVELENGTH: distance between 2 crests or troughs (transverse waves) or distance between 2 compressions/ rarefactions (longitudinal waves)

AMPLITUDE: maximum distance the particles move from its usual resting position. Determines loudness of sound/ brightness of light.

FREQUENCY: number of complete waves passing a point every second or number or complete vibrational cycles per second. Measured in hertz (Hz) // cycles per second.

SOUND-

SOUND: caused by vibration of particles, but not all vibrations can be heard as sound.

Frequency of sound related to pitch (e.g high f= high pitch)

Amplitude of sound related to volume (e.g low amp= quiet sound)

Sound reflects off surfaces, we hear sound waves as echoes

Hard, smooth surfaces are good at reflecting sound. (vice versa)