Cells and cell division Flashcards
(23 cards)
Cell membrane
Surrounds entire cell
Semi-permeable
Formed from a phospholipid bilayer with proteins embedded
Cytoplasm
Fluid inside the cell
Contains water, salts, nutrients and organelles
Nucleus
Control centre
Contains DNA packaged into chromosomes
Nucleolus
Active area of the nucleus containing enzymes and RNA
Lysosomes
Contains digestive enzymes
Digest bacteria and debris
Mitochondria
Energy production
Centrosome
Made up of centrioles
Involved in cell division
Ribosomes
Attached to endoplasmic reticulum
Protein synthesis
Golgi apparatus
Secretes proteins out of the cell
Cilia
Small hairs on the cell surface that move fluids and mucous
Found in the respiratory tract
Microvilli
Small projections of the cell membrane that increase surface area
Structures that can be seen under a light microscope
Cell membrane
Cytoplasm
Lysosomes
Nucleus
Nucleolus
Mitosis
Two cells
Identical to the parent cell
Identical to each other
Same number of chromosomes
Meiosis
Occurs in the production of sex cells
Four cells
Different to the parent cell
Different to each other
Half the number of chromosomes
Stage 1 - Interphase
Resting phase between cell divisions
Stage 2 - Prophase
Preparation phase
Genetic material in the nucleus replicates itself and the centrosome starts to form the mitotic spindle
Stage 3 - Metaphase
Chromosomes line up on the mid-point and attach to the spindle
Stage 4 - Anaphase
Spindle acts as tiny ropes and pulls the chromosome apart
Each side of the cell has one full cell of DNA
Stage 5 - Telophase
Nuclear membrane reforms and the cell begins to seperate into two cells
Phase of meiosis
Prophase 1
Metaphase 1
Anaphase 1
Telophase 1
Prophase 2
Metaphase 2
Anaphase 2
Telophase 2
Labile cells
Continually dividing
Stable cells
Cells that do not normally divide but can start to divide in response to injury
Permanent cells
Cannot divide after birth
