B1 and B2 - Characteristics of Living Organisms and Cells Flashcards
Characteristics of life: MRS GREN
- Movement
- Respiration
- Sensitivity
- Growth
- Reproduction
- Excretion
- Nutrition
Movement
An action by an organism or part of an organism causing a change of position or place
Sensitivity
The ability to detect or sense stimuli in the internal or external environment and to make appropriate responses
Respiration
The chemical reactions that break down nutrient molecules in living cells to release energy for metabolism
Growth
A permanent increase in size and dry mass by an increase in cell number or cell size or both
Reproduction
The processes that make more of the same kind of organism
Excretion
Removal from organisms of toxic materials, the waste products of metabolism (chemical reactions in cells including respiration) and substances in excess of requirements
Nutrition
Taking in of materials for energy, growth and development; plants require light, carbon dioxide, water and ions; animals need organic compounds and ions and usually need water
Parts of an animal cell
Nucleus, cytoplasm, cell membrane, mitochondria
Parts of a plant cell
Cell wall, cell membrane, cytoplasm, mitochondria, chloroplasts, vacuole
Function of nucleus
Directs all the cells activities; contains the cells DNA
Function of cell membrane
Partially permeable membrane which controls substances that move in and out of the cell
Function of chloroplasts
Structures found in the cells of green parts of plants only (leaves and stems) which contain a green pigment called chlorophyll in which photosynthesis occurs
Function of vacuole
Stores materials such as water, salts, proteins and carbs
Function of rough endoplasmic reticulum
Membrane-bound structure involved in protein synthesis; covered in ribosomes and forms around the nucleus
Function of cytoplasm
Liquid that makes up most of the cell in which chemical reactions happen
Function of mitochondria
Floating in the cytoplasm where energy is released from glucose from food; where most respiration happens
Function of cell wall
A tough outer layer of the cell, which contains cellulose to provide strength and support to the plant
Function of ribosomes
Protein synthesis (making proteins)
Function of enzymes
Biological catalysts, increase rate of chemical reactions
Solute
A substance that is dissolved in a solvent
Solvent
The substance in which the solute dissolves
Soluble
A substance able to dissolve
DNA
Contains genetic information for the building and functioning of the cell
Electron microscope
Microscope that forms an image by focusing beams of electrons onto a specimen
Light microscope
Microscope that uses a beam of light passing through one or more lenses to magnify an object
Nosepiece
Holds the objectives and can be rotated to change the objective lens to the specific lens one you want to use
Diaphragm
Controls the amount of light passing through the slide; located below the stage and is usually controlled by a round dial
Illuminator
Low voltage bulb which supplies light through the stage and onto to the specimen (sometimes mirrors)
Solution
The final product of dissolving (solute + solvent)
Eyepiece (ocular lense)
Magnifies an image, usually 10x
Eyepiece tube / body tube
Holds the eyepieces in place above the objective lens
Objective lense
Most compound microscopes come with three or four objective lenses that revolve on the nosepiece (low, medium, high) The most common objective lenses have power of 4X, 10X and 40X