science from revision sheet

What is weight

Weight is a downward gravitational force exerted on a body’s mass by a planetary body. It is measured in newtons because it is a force and can change depending on the local gravitational field strength.

What is mass.

Mass is a fundamental measurement on how much matter is in an object. It is measured in kilograms and stays completely constant anywhere in the universe.

What is the weight equation

Weight(N)=Mass(kg)xgravitational field stretching(N/kg)

The gravitational field strength of the earth is 10 N/kg and the gravitational field strength of the moon is 1.7 N/kg. What is the weight of an object with a mass of 10kg on both planets?

On earth=100 N

On the moon=17 N

What are non contact forces

Non-contact forces only pull or push across an distance., without physical surface contact.

What are contact forces

Contact forces can only push or pull when two surfaces interact with each other.

What is velocity

The speed in a specific direction

What is the net resultant force when forces are balanced

It is zero

What two forces must be balanced for something to float on water

Weight and upthrust.

What is terminal velocity

Terminal velocity is when an object stops accelerating and maintains a constant speed known as terminal velocity

What is a species

A species is a separate group of structurally similar organisms capable of interbreeding to produce fertile offspring.

What is a population

A population is all individual organisms belonging to the same species living within a defined geographical area at the same time.

What is a community

The sum total of multiple interacting populations of different species sharing the same environment.

Are producers autotrophic

Yes they produce there own food through photosynthesis.

What do herbivores exclusively feed on

Autotrophic producers

What title do omnivores have in the food chain

Secondary or tertiary consumers

What do the arrows represent

The direction of energy flow.

What is interdependence

Interdependence is the reliance between living organisms on other organisms or the environment for survival.

Intra-specific competition is when

Organisms from the same species compete

Inter-competition is when

Organisms of different species compete

What is selective breeding( artificial selection)

The process by which humans select individuals with desired characteristics and breed them together over multiple generations to make these characteristics more common in the species.

What is germination and fertilization

Fertilization is the biological process where female and male gametes fuse together to create a new organism. Germination is the sprouting of a seed.

What are some examples of abiotic factors

Non-living, physical or chemical elements in an ecosystem that dictate animal/plant health. Light intensity, temperature, water availability, soil pH.

What are some examples of biotic factors

Influences coming directly from living organisms within the environment. Caterpillar infestations, weed competition, bird overpopulation.

What are the seven life process that all living organisms must do.

Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition.

Difference between breathing and cellular respiration

Breathing is the physical act of moving air into and out of the lungs, while cellular respiration is the chemical process where cells break down glucose to generate usable energy.

Role of mitochondria

It is the site of aerobic cellular respiration, responsible for converting biochemical energy from glucose into accessible energy for the cell.

Role of nucleus

Nucleus houses DNA and coordinates cell activities.

Role of cytoplasm

The internal jelly-like matrix where metabolic chemic reaction proceed.

Role of cell membrane

The semi-permeable barrier regulating transport into and out the cell.

Role of cell wall

Rigid outer boundary composed of cellulose providing structural support

Permanent vacuole

Large internal fluid-filled space containing cell sap to maintain cellular turgor pressure

Chloroplast

Sites containing chlorophyll molecules to capture photons for photosynthesis.

What are the levels of structural complexity specialized cells, tissues, organs, organ system, organism.

What is the heart

A muscular pump that drives blood through the circulatory network to supply oxygenating tissues.

What is the kidney

Performs metabolic filtration to remove waste products like urea from the blood stream, regulating osmotic pressure

What is the liver

Synthesizes digestive bile and chemically breaks down toxic or poisonous compounds entering the body.

What is the stomach

A muscular sac that churns food mechanically while using acid and gastric enzymes to break down nutrients.

What are lungs

The principal organs of the respiratory system, fascinating gas exchange between the atmosphere and blood.

What is the circulatory system

Includes heart and blood vessels; specialized for mass transport

What is the respiratory system

Includes the trachea, bronchi, lungs and diaphragm; handles external ventilation and gas exchange.

What is an element

A chemical substance consisting entirely of a single type of atom. It cannot be broken down chemically into anything simpler.

What a compound

A chemical combination of two or more different types of atoms chemically bonded together in fixed, definite proportions.

What is a mixture

A physical combination of two or more elements or compounds that occupy the same space but are not chemically bonded. They can be separated using physical technique like filtration or evaporation