Unit 1A Flashcards
Multicellular
Made of many cells
Nucleus
A structure inside cells which contains DNA. It controls the cell’s activities.
Cytoplasm
The site of chemical reactions in cells
Cell membrane
Forms the boundary of the cell and controls what goes in and out.
Vacuole
A compartment inside plant cells that stores dissolves sugars and salts.
Chloroplast
A structure inside plants cells where photosynthesis occurs, producing sugar.
Cell wall
A supporting structure around the outside of plants cells, which helps them to keep their shape.
Specialised cell
A cell with a particular shape, that is adapted to perform a specialised function. eg. a nerve cell, muscle cell or sperm cell.
Tissue
A group of similar specialised cells that work together to carry out a particular function. eg. muscle cells are grouped together to form muscle tissue.
Organ
Organs are made of several types of tissue working together. eg leaf, small intestine
Micrometre
A unit for measuring cells. 1mm
(millimetre) = 1000 micrometres
Graticule
A tiny scale placed into the eyepiece of a microscope. Used for measuring cells.
Zygote
Fertilised egg.
Mitosis
Cell division used to create identical copies of an original parent cell.
Needed for growth and repair of damaged tissues.
Chromosomes
Structures inside the nucleus that appear before cell division. They are made of DNA.
Chromatids
The 2 identical copies of the original chromosome that make up a replicated chromosome.
Centromere
Holds the 2 chromatids together until it is split apart during mitosis as the chromatids separate.
Cancer
Body cells divide in an uncontrolled way to create a mass of cells called a tumour.
Agar plate
Petri dish filled with nutrient jelly (agar). Used for growing micro-organisms.
Sterile (aseptic) technique
All equipment, hands and work areas need to be cleaned with heat/disinfectant to prevent growth of unwanted micro-organisms.
Colony
A group of micro-organisms growing on an agar plate. Each colony can be seen as an individual dot.
DNA
A molecule found in the nucleus of cells. Contains the instructions for building protein molecules.