Biology - Chp. 2 The Cell

Question 1

What processes do cells carry on

Answer 1

• Intake of nutrients
• Removal of waste
• Movement
• Growth and reproduction
• Response to stimuli
• Exchange of gases

Question 2

Are cells prokaryotic or eukaryotic

Answer 2

Both, there are many types of cells. Some do contain a nuclei and complex organelles while others do not

Question 2

What elements make up the structure of cells

Answer 2

Carbon, hydrogen, oxygen and nitrogen

Question 3

What organic compounds make up cells

Answer 3

1. Carbohydrates – e.g. sugar, starch, cellulose
2. Lipids – e.g. fats and oils
3. Proteins – e.g. muscles, hormones, enzymes
4. Nucleic acids – e.g. DNA and RNA

Question 4

What is the Cell Membrane

Answer 4

• 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

Question 5

What is the nucleus

Answer 5

• 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

Question 6

What is the cytoplasm

Answer 6

• 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)

Question 7

What is the cell wall

Answer 7

• Found in plants, bacteria, protists and fungi (all plant cells)
• Rigid frame provides support and strength

Question 8

What are chloroplasts

Answer 8

• Found in plants, bacteria, protists and fungi (all plant cells)
• In the site of photosynthesis
• CO2 + H2O + light energy = C6H12O6 + O2

Question 9

What are centrioles

Answer 9

• only found in animal cells
• involved in cell division

Question 10

What are vacuoles and vesicles

Answer 10

• bound by a membrane
• stores nutrients, products of secretion, fats and water
• Plant cells have one large vacuole
• Animal cells have many small vesicles

Question 11

What are lysosomes

Answer 11

• Sacs within the cell that contain strong chemicals that break down and recycle materials

Question 12

What are ribosomes

Answer 12

• Granules (either floating in cytoplasm or attached to ER) that are the site of protein synthesis

Question 13

What the the endoplasmic reticulum

Answer 13

• series of tubes extending from the nuclear envelope
• Rough ER is associated with protein synthesis
• Smooth ER is associated with lipid production

Question 14

What is the Golgi Apparatus

Answer 14

• flat disc-shaped sacs
• modifies and packaging substances to be transported from ER to be used in or out of the cell

Question 15

What are mitochondira

Answer 15

• site of cellular respiration
• chemical energy is converted into ATP energy for growth, transport, repair and movement
• C6H12O6 + O2 -> CO2 + H20 + ATP energy

Question 16

What is the plasma membrane

Answer 16

• Cell Membrane
• maintains equilibrium within the cell
• semi-permeable

Question 17

What is the plasma membrane made of

Answer 17

• 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)

Question 18

What is the current cell membrane model

Answer 18

• fluid-mosaic model
• membrane changes pattern of proteins and carbohydrates on surface
• fluidity allows proteins to move membrane and cell to change shape

Question 19

What are the principles of the particle model of matter

Answer 19

1. All matter is made of particles, but different substances vary in size and composition
2. Particles of matter are constantly moving or vibrating, Adding or taking away energy will affect their movement
3. Particles of matter are attracted to one another or bonded together
4. Particles with the most space between them are gas, and the smallest in solid

Question 20

What is a concentration gradient

Answer 20

• relative difference in concentration of a substance between two areas
• molecules will try to reach an equilibrium

Question 21

What is diffusion

Answer 21

• 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

Question 22

What is osmosis

Answer 22

• 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

Question 23

What is facilitated diffusion

Answer 23

• 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

Question 24

What is active transport

Answer 24

• Transport of materials across membrane using protein pumps/carrier proteins that require energy
• goes against concentration gradient

Question 25

What is Endocytosis and exocytosis

Answer 25

• 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

Question 26

What are membrane proteins and disease

Answer 26

receptor proteins are studied to prevent HIV infection and target cancer cells

Question 27

What is synthetic membrane technology

Answer 27

• artificial cell membranes (liposomes) can be used to deliver medication to specific cells through endocytosis
• uses transdermal patches to deliver medication

Question 28

What is reverse osmosis

Answer 28

water is filtered by forcing it through membrane against concentration gradient

Question 29

What is kidney dialysis

Answer 29

waste is filtered from blood using semi-permeable membrane

Question 30

How does cell size affect its function

Answer 30

• 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