Biology - Chp. 2 The Cell Flashcards
What processes do cells carry on
- Intake of nutrients
- Removal of waste
- Movement
- Growth and reproduction
- Response to stimuli
- Exchange of gases
Are cells prokaryotic or eukaryotic
Both, there are many types of cells. Some do contain a nuclei and complex organelles while others do not
What elements make up the structure of cells
Carbon, hydrogen, oxygen and nitrogen
What organic compounds make up cells
- Carbohydrates – e.g. sugar, starch, cellulose
- Lipids – e.g. fats and oils
- Proteins – e.g. muscles, hormones, enzymes
- Nucleic acids – e.g. DNA and RNA
What is the Cell Membrane
- protective barrier of the cell
- allows transport of needed materials into the cell and waste materials out
- important for cell communication and for recognition of molecules
What is the nucleus
- Contains DNA (genetic material of the cell and directs all cellular activities)
- Surrounded by the nuclear envelope, which has pores and allow transport of materials into and out of the nucleus
What is the cytoplasm
- gel-like substance inside the cell membrane
- Contains nutrients needed for processes of life
- organelles are suspended in gel
- allows for cytoplasmic streaming (movement of organelles and molecules within the cell)
What is the cell wall
- Found in plants, bacteria, protists and fungi (all plant cells)
- Rigid frame provides support and strength
What are chloroplasts
- Found in plants, bacteria, protists and fungi (all plant cells)
- In the site of photosynthesis
- CO2 + H2O + light energy = C6H12O6 + O2
What are centrioles
- only found in animal cells
- involved in cell division
What are vacuoles and vesicles
- bound by a membrane
- stores nutrients, products of secretion, fats and water
- Plant cells have one large vacuole
- Animal cells have many small vesicles
What are lysosomes
- Sacs within the cell that contain strong chemicals that break down and recycle materials
What are ribosomes
- Granules (either floating in cytoplasm or attached to ER) that are the site of protein synthesis
What the the endoplasmic reticulum
- series of tubes extending from the nuclear envelope
- Rough ER is associated with protein synthesis
- Smooth ER is associated with lipid production
What is the Golgi Apparatus
- flat disc-shaped sacs
- modifies and packaging substances to be transported from ER to be used in or out of the cell
What are mitochondira
- site of cellular respiration
- chemical energy is converted into ATP energy for growth, transport, repair and movement
- C6H12O6 + O2 -> CO2 + H20 + ATP energy
What is the plasma membrane
- Cell Membrane
- maintains equilibrium within the cell
- semi-permeable
What is the plasma membrane made of
- phospholipids (phosphate head and fatty acid tail, forms a bilayer when in water)
- receptor proteins
- transport proteins
- glycoproteins (proteins with sugar attached, recognition proteins for communication and identification)
What is the current cell membrane model
- fluid-mosaic model
- membrane changes pattern of proteins and carbohydrates on surface
- fluidity allows proteins to move membrane and cell to change shape
What are the principles of the particle model of matter
- All matter is made of particles, but different substances vary in size and composition
- Particles of matter are constantly moving or vibrating, Adding or taking away energy will affect their movement
- Particles of matter are attracted to one another or bonded together
- Particles with the most space between them are gas, and the smallest in solid
What is a concentration gradient
- relative difference in concentration of a substance between two areas
- molecules will try to reach an equilibrium
What is diffusion
- Passive transport (adding energy will increase rate of diffusion
- net movement of particles from areas of high to low concentration
- Only small, uncharged, polar molecules with pass through membrane
What is osmosis
- Passive transport
- diffusion of water across membrane, from high to low areas of solute concentration
- When the concentration of solute is greater outside the cell and inside, the outside environment is called hypertonic and the inside is hypotonic
- When concentration is equal, they are isotonic, but movement will still occur
What is facilitated diffusion
- Passive transport
- Uses transport proteins to move large or charged particles across the cell membrane
- Transport proteins have a 3D shape and are highly selective (recognize particular atoms+molecules by shape size and charge
- Channel proteins, type of transport proteins, provide water-filled passage for charged ions when open
- Carrier proteins, type of transport proteins, binds to solute and changes shape to release solute in cell
What is active transport
- Transport of materials across membrane using protein pumps/carrier proteins that require energy
- goes against concentration gradient
What is Endocytosis and exocytosis
- Transport of molecules that can’t dissolve in water or are too large to cross membrane
Exocytosis - a membrane vesicle will fuse with membrane to release contents
Endocytosis - part of the membrane folds around the items to bring it into cell
What are membrane proteins and disease
receptor proteins are studied to prevent HIV infection and target cancer cells
What is synthetic membrane technology
- artificial cell membranes (liposomes) can be used to deliver medication to specific cells through endocytosis
- uses transdermal patches to deliver medication
What is reverse osmosis
water is filtered by forcing it through membrane against concentration gradient
What is kidney dialysis
waste is filtered from blood using semi-permeable membrane
How does cell size affect its function
- must have high surface area to volume ratio
- helps with effective oxygen, nutrient and waste transport
- many cells are specifically designed to increase surface area
