organisation of organisms

Class notes

Organism is a living thing
All organisms are made up of the same basic structure called a cell

Cells

The basic structural and functional unit of life
- Structural
- Functional

The structure of a basic animal plant cell (advice for marks)

Neat lines
Basic
Don't use arrows

Partially permeable

Only some or part of the cell can pass

Cell wall

Permeable
- Let's water pass through easily

Semi vs partially permeable

Semi
- Half of the content can pass
Partially
- Some type of molecules can pass

Vacuole

Plant
- Keeps shape
- Permanent
- Contains cell sap
  - Water, salts and sugars
  - Contributes to nutrition of cell
Animal
- Temporary
- Can serve as food or chemical storage vesicles
Applies pressure on cell wall

Mitochondria

Aerobic respiration
- Provision of energy

Cytoplasm

Anaerobic respiration
- Provides energy but not as much as mitochondria

Prokaryotes

Pro - before
Karyotes - nucleus

Specialised cells

These cells do a specific/particular functions in the body

Class task - 27 January

For your chosen cell, write down the following (ff):

Name
- Doctor
Functions
- Heal
Way it is adapted/modified
- How it may be different from others
- How it is "dressed" compared to other cells
  - Has stethoscope
  - Think of ciliated epithelial cells
Relate the function to its adaptation
- Always needs a stethoscope to check their patients quickly

Root hair cell (name)
- On the edge of the root for more water availability and easier absorptions (functions)
- Absorbs and transports water and mineral ions into plant from the ground (functions)
- Long, thin hairs (adaption)
- Tip of roots (adaption)
  - large surface area to help with absorptions
  - Penetrate through soil particles
  - For osmosis to take place
    - It filters out any molecules they don’t want as they are semipermeable
  - Formed from some of the epidermis cells
    - Epidermis of root
      - Outer layer of the root
  - Have a lot of mitochondria to help to keep an active transportation

Cells makes tissues -> tissues make organ -> organs make organ system -> organ system make body

Chapter 2

Animal cell

Cell membrane

Around the outside
Thin layer of protein and fat
Controls what goes in and out the cell
Partially permeable
- Some substances can pass through but others can't
Separates inside content from outside content

Cytoplasm

Clear jelly
Almost all water
- 70%
Metabolic reactions take place inside
Other parts of cell flow inside it
Many substances dissolved in it
- Protein
- Salts
- Fatty acids
- Sugars
- Amino acids

Jelly like substance in which chemical reactions take place

Nucleus

Genetic information stored inside
- Chromosomes
  - Made of DNA

Co-ordinates many activities that take place in the cell

Ribosomes

Found scattered around the cytoplasm
Makes protein
Link together into chains

Place where protein synthesis takes place

Vesicles

Small vacuole
Transport recycled waste and material that the organism needs for survival

Rough endoplasmic reticulum

Transporting proteins
Holds ribosomes on it
Endoplasmic reticulum
- Without outer layer of ribosomes
- Storage of lipids
In plant and animal cells

Plant cell

Cell wall

All plants have this
Made of cellulose
Polysaccharides
Strong covering for cell
Protects cell
Keeps cell shape
- Stops cell from bursting
Fully permeable

Vacuole

Fluid-filled space
Surrounded by its own membrane
Large, permanent
Contains cell sap
- Solution of sugar and other substances
Presses outward on cell wall to keep shape

Mitochondria

In plant and animal

Aerobic respiration happens
- Energy released from glucose
- Uses oxygen

Chloroplast

Green parts of plant
- Colour from chlorophyll
Absorbs energy from sun
- Used to make food for plant
Contains starch grains
- Tiny pieces of starch
- Stored in plant cells

Bacterial cells

Have cell wall
- Made of peptidoglycan, not cellulose
- Same function as plant
  - Helps support cell
  - Stop it from bursting
Partially permeable membrane
- Pressed against inside of cell wall
- Controls what enters and leaves
Cytoplasm and ribosomes
- Same functions as animal and plant
No mitochondria or chloroplasts
No nucleus
- Biggest difference between animals and plants
- It is in its name, prokaryote
  - 'Pro' meaning before
  - 'Karyote' meaning nucleus
  - Eukaryote is opposite
Circular DNA
- DNA has same functions as plants
- Provides instructions for making proteins
- Some have one; some more
- Name is plasmids
  - Use it for genetic modifications

Specialised cells

Specialised cell	Where it is found	Function	Where you can find out more
Ciliated cell	Lining the trachea and bronchi of animals	Cilia move mucus upwards	11.2
Neurone	In the nervous system of animals	Conducting electrical impulses	12.1
Red blood cell	In the blood of mammals	Transporting oxygen	9.4
Sperm cell	Produced in the testes of mammals	The male gamete in sexual reproduction	15.1
Egg cell	Produced in the ovaries of mammals	The female gamete in reproduction	15.1
Root hair cell	Near the tips of the roots of flowering plants	Absorption of water and mineral ions	8.2
Palisade mesophyll cell	In the leaves of flowering plants	Photosynthesis	6.2

Multicellular organisms have a lot of cells
- Not all alike
- Most cell do have same features, just shaped differently
Perform particular function from rest of cells
- Different from other to perform different tasks

Tissues

Specialises the same activity together
- Found together
Cells that do a similar task that are found together
Both in plants and animals

Organs

Group of different tissues
- Carry a function together
In animals and plants
- Stomach for animals
- Leaves for plants
Organ system
- Several organs working together to perform a particular function

Sizes of specimens

In microscopy the specimen are extremely small and ideally should be measured in very small units
- Cannot be done without microscope
- Micrometre
  - Mm
  - 1mm = 1000Mm
- Nanometre

Microscope

Glass lenses used to magnify cell or anything microscopic
To see anything smaller that a normal microscope can't show
- Electron micrograph
  - Uses a beam of electrons

Ocular lens [eye piece]	Diopter adjustment	Nose piece	Head
Magnifies the image produced by the microscope's objective so that it can be seen by the human eye	Raises or lowers the eyepiece in order to adjust the focus for each eye	Holds the objective lenses and attaches them to the microscope head	Houses the eyepiece and objective lenses

Arm[Carrying handle]	Stage clip	Aperture	Mechanical stage
Supports the head of the microscope and is also used when carrying the microscope	Holds the slides in place	Allows transmitted light to reach the stage. Gathers light and resolves fine specimen details while working at a fixed object distance	To hold the microscope slide in order to hold it steady and to reposition it when needed

Coarse adjustment	Fine adjustment	Diaphragm	Condenser
Rapid or rough positioning of the specimen at the focal point of the objective lens	To bring the specimen into sharp focus under low power	To control the amount of light reaching the specimen being observed	Focus light onto a specimen. Gathers wavefronts from the microscope light source and concentrate them into a cone of light.

Illuminator [light source]	Light switch	Brightness adjustment	base
To provide even, high intensity light at the place of the field aperture, so that light can travel through the condenser to the specimen	Allows the user to control the intensity of the light that passes through the specimen being observed on the microscope slide	Adjust the intensity of the light passing through the microscope	It serves as a support for microscope

Stage controls

Allows the movement of the stage back and forth in order to allow examination of a microscope