Bio final revision (term 3___notes-2.8,2.9,3.5,4.1,4.2,4.3

Tissues & organs in an animal(2.8)

Level of organisation

• All multicellular organisms have 5 levels of organisation:

LVL1: Cell

LVL2: Tissue

LVL3: Organ

LVL4: Organ system

LVL5: Organism

• Tissues are groups of similar types of cells that work together to carry out specific tasks

• Most animals, including humans have 4 main types of tissues they are:

1- Muscle tissue:makes movement possible

2- Connective tissue:provides structure and support

3-Nervous tissue:carries messages to and from the brain

4- epithelial tissue:forms the protective outer layer of the skin and the thining of major organs and internal body cavities

Meanings

1-Cell: the building blocks of life

2-Tissue:group of many specialised cells working together to carry out a function

3-Organs:made up of 7 different tissues working together to carry out a function

4-Organ System:made up of several different organs working to carry out a function

5-Organism:made up of many different organs and organs and organ system working together

• TISSUES WORK TOGETHER TO FORM ORGANS

• Complex jobs in organisms require more than one type of tissue.

• Organs are groups of different tissues working together to preform a particular job.

Organs and their jobs:

• Brain- controls the body

• Lungs- take in oxygen/remove carbon dioxide.

• Liver- remove toxins & produces bile to help digestion

• Intestine- absorbs nutrients from food

• Kidney- filters the blood & produce urine

• Bladder- stores urine

• Stomach- digests food

• Heart- pumps blood

• Most organs do not function alone

• Organ systems are grows of different organs that work together to complete a series of tasks.

• The digestive system in made of:

1-The stomach

2-The small and large intestines

3-the liver

• Blood absorbs ad transports nutrients from food to cells throughout the body.

Tissues and organs in plants(2.9)

• The plants we see around us have 7 levels of organisation:

1.Organelle: Tiny structures inside a cell (nucleus, cell wall etc.)

2.Cell: The smallest unit of life.

3.Tissues: A group if cells working together.

4.Tissues system: Groups of different tissues that work together as a system.

5.Organ: A part of the plant made of multiple tissue systems.

6.Organ system: A group of organs that work together

7.Organism: The entire plant (a living being)

What they do:

1.Organelle:Each organelle has a special job (nucleus:control the cell, etc.)

2.Cell:Does basic life functions, like make food, using energy and diving to grow

3.Tissue:Performs a specific job

4.Tissue system:Supports bigger plant functions.

5.Organ: Does a big job for the plant

6.Organ system:Handles major functions

7.Organism:Grows, reproduce, and survives using all its systems and parts.

Types of tissues in plants:

• Xylem tissue:carries water

• Phloem tissue: carries food

• Palisade tissue:photosynthesis(absorb sunlight to make glucose ’plant food’)

They also have another system:

The reproductive system

but in most plants its only there for part of the year

Function of plants organs

organ 1:LEAVES- function: photosynthesis (shoot system)

organ 2:STEMS- function: supports &transport (shoot system)

organ 2:ROOTS- function: absorption & storage & conduction (root system)

• Each plant tissue contains a particular types of specialised plant cells, working together to carry out a function in the plant.

• Food is made in a plants leaves

• Food is needed in a plants cells

PICTURE OF TISSUES:

The decomposer(3.5)

What is a decomposer?

• A decomposer is a living thing that breaks down dead plants, animals and waste, turning them into nutrient. that go back into the soil.

Examples of decomposers:

• Fungi(like mushrooms and mold)

• Bacteria

• Worms

• Some insects (like beetles and maggots)

What do they do?

• Break down dead stuff

• Return nutrients to the soil (like leaves, animal, waste)

• Help plants grow by making the soil rich

• Release carbon dioxide, water and nutrients into the environment.

Why are they important?

• without decomposers, dead things would pile up, and plants wouldn’t get the nutrients they need. so basically, they keep the earth clean and healthy!

The physical environment(4.1)

key terms

• Abiotic: non-living (light,temperature,water,PH)

• Biotic: living (plants,animals,bacteria,fungi)

Why water is important?

• Covers 71% of earths surface

• Human body=60% water

• Needed for:

  - Transporting minerals & nutrients

  - Photosynthesis body temperature

  - Dissolving substances (solvent)

Water in organs

Most amount of water: lungs(83%)

Least amount of water: bones(31%)

Properties of water

1. Good solvent- dissolves substances(important cells)

2. High heat capacity- helps regulate temperature

3. Ice floats- insulate water life in water

Why is it important that ice floats?

• Because it forms a layer on top of water and keeps animals below from freezing.

Why does water being a good solvent matter?

• Because it helps disslove and carry nutrients in living things.

The water cycle(4.2)

• Water is always moving in and around earth. It never goes away but it does change form.

Its a gas in the atmosphere

Its a liquid in the surface

Its a solid in the glaciers

The movement of water around earth is called: the water cycle

The sun is the driving force of the water cycle.

There are 5 important process to the water cycle.

Steps of a water cycle:

1-Evaporation

2-Condensation

3-Precipitation

4-Transpiration

5-Runoff

1.Evaporation

The process of liquid water training into water vapour (gas).

• The sun energy evaporates the water.

• Liquid —> Gas

2.Condensation

the process of water vapour (gas) turning into liquid water.

• Forms clouds

• Gas —> Liquid

3.Precipitation

The process of liquid water falling back to earth.

• 4 types:

1.Water(liquid)

2.Snow(solid)

3.Hail(solid)

4.Sleet(solid)

4. Transpiration

process of plants releasing water vapour (gas) into the environment

Leaving have tiny openings called stomato. Plants open and close the stomato to release water vapour.

5. Runoff

The process of water flowing back to rivers,lakes,and the ocean.

Process of the water cycle:

Evaporation

The sun warms water on earths surface it causes liquid water to change into a gas this process is called

Condensation

In the atmosphere, water vapour cools and changes back into liquid form this process is called condensation tiny water droplets form on dust particles in the atmosphere to form cloud droplets. Cloud droplets combine to form clouds

Precipitation

Clouds eventually become “too heavy” and the water falls from the atmosphere to earth surface. This process is called precipitation water can fall as liquid droplets (rain) solid crystals (snow) or frozen droplets (hail)

Transpiration

plants need water just like we do and they store water in their leaves. Leaves have small openings. when the sun warms plants, it causes water to evaporate out of the leaves,through the small openings this process is called transpiration

Collection(runoff)

precipitation that falls to earths surface move from high to low elevation. This water is called runoff. Runoff collects in rivers that flow into lakes and oceans this process is called collection

Global warming and water cycle(4.3)

What is global warming?

• Burning fossil fuels (cars,electricity) releases carbon dioxide (CO₂)

• CO₂ traps heat —> Earth gets warmer=climate change

Impact on the water cycle

Global warming causes:

• Icecaps/glaciers melt—> sea level rise

• More evaporation—> more rain in some places

• Droughts in other places

Melting ice & Rising seas

• Most freshwater is stored as ice in glaciers

• Melting ice—> less freshwater + rising sea levels

• Some islands and coastal areas may disappear in 100 years

More floods

• Warmer air holds water—>bigger storms

• Heavy rain causes flooding, especially in coastal areas

• floods damage homes, soil,and lives

More droughts

• Hotter weather dries soil

• No rain= drought

• When it does rain, its too fast= runoff not soaking in

Rain changes

• Some areas get more rain (north Europe, east Africa)

• others get less rain(north Africa,middle east)

What causes sea levels to raise?

- melting ice and warmer oceans that expand

What damage do floods cause?

-They destroy homes, wash away soil, and can cause deaths.

Why are droughts lasting longer?

- Because hotter weather dries the soil and theres less rain for longer time