Cell biology Flashcards
What is a prokaryote?
A single celled organism
What is a eukaryote?
A multi-celled organsim
What are the differences between prokaryote and eukaryote?
Prokaryote’s genetic material is called nucleiod which does not have a membrane. It is often small. Eukaryote has genetic material in nucleus which has a membrane (nuclear envelope) and often large in size.
What defining characteristics does an animal cell have?
Lysosome, Centrioles, Flagella (apart from some plant sperm), tight junctions, desmosomes and gap junction
What defining characteristics does a plant cell have?
Chloroplast, central vacuole, tonoplast, cell wall and plasmodesmata
What are the different organelles?
Plasma membrane, Cytoplasm, Cytosol, Cytoskeleton, Centrome, Flagella/cillia, nucleus, ribosome, endoplasmic reticulum, lysosome, perioxisomes, golgi apparatus, mitochondria, chloroplasts, central vacuole and cell wall.
What is an organelle?
Internal organs of a cell
What is the function of the plasma membrane?
Selective barrier allowing o2, nutrients and waste in
What is cytoplasm?
cell content without nucleus
What is cytosol?
cell content without all organelles
What is the cytoskeleton and its function?
matrix of fibres (microtubules, microfilaments, intermediate filaments) inside cytoplasm. Gives mechanical support to cell and maintains shape. Provides anchorage for organelles, allows cell/organelle movement. Regulates biochemical activities
What is the centrome and its function?
Made from 2 centrioles (9 microtubules in cylindrical shape). Play part in all cell division.
What is flagella and cillia and their functions?
They are tails on outside of cells allowing for locomotion. Cillia is smaller and many whereas flagella is few but longer. They have beating pattern. Cilia is found in windpipe and flagella on sperm cells
What is the nucleus and its function?
Contains genetic material. Has double membrane. Nuclear lamina- inside and provides structure. Nuclear matrix- grid structure throughout nucleus. Creates messenger RNA (mRNA). Nucleous is site of ribosomal RNA creation (rRNA).
What is the DNA structure and chromosome?
DNA is double helixed with 46 chromosomes. Chromosome is DNA and chromatin
What is endoplasmic reticulum?
Smooth ER (smooth) and makes hormones and lipid membrane. Rough ER (has ribosomes) and assists in assembly of many proteins which are transported in vesicles.
What are Lysosomes?
Type of vesicle, digestion of macromolecules by use of hydrolytic enzymes
What is phagocytosis?
Process of digesting external particles in bacteria. Human cells (macrophages) destroy bacteria, viruses and other invaders.
What is autophagy?
Recycling of cells own products
What are peroxisomes?
Type of vesicle, carries out oxidation reactions that break down fatty acids and amino acids. Detoxify many poisons in liver cells. By product is hydrogen peroxide, h2o2.
How is hydrogen peroxide broken down?
By peroxisonal enzymes into water and oxygen
What is the golgi apparatus?
Made from stacks (cisternae) with an ‘arrival’ (cis) and ‘departure’ (trans) side. A cisternae matures from cis to trans, releasing products to move where needed.
What is the mitochondria?
ATP conversion from sugars, fats and other fuels. Contains DNA, can be 1 or 1000’s. 2 membranes; outer is smooth and inner is convulated (cristae). Inside cristae is mitochondrial matrix (cytoplasm of mitochondria). Powerhouse of cell
What are the chloroplasts?
Plant powerhouse for photosynthesis. Part of family called plastids. Chromoplasts give fruits and flowers their colour. Could contain pigment, helps with growth of plants
