Unit 4: Microscopes, cell structure and function

Question 1

light microscope

Answer 1

a type of microscope that uses light and lenses to magnify very small objects, can see inside of cells as light passes through the samples

Question 2

cell stains

Answer 2

chemical stains/dyes are used to be able to see otherwise transparent cells or structures under a microscope

Question 3

electron microscope

Answer 3

a type of microscope that uses beams of electrons to create images of once living things (only works in a vacuum), greater magnification than light microscopes

Question 4

cell theory

Answer 4

1. all living things are made of cells
2. cells are the basic units of life (structure and function)
3. new cells are produced from existing cells

Question 5

autotroph

Answer 5

makes its own food

Question 6

heterotroph

Answer 6

has to consume other organisms for food

Question 7

prokaryote

Answer 7

cells that do not enclose DNA in nuclei, generally smaller and simpler, older, unicellular

Question 8

bacteria

Answer 8

prokaryotic, unicellular, have cell walls with peptidoglycan, can be autotrophic or heterotrophic

Question 9

archaea

Answer 9

prokaryotic, unicellular, have cell walls without peptidoglycan, can be autotrophic or heterotrophic, more similar to eukarya

Question 10

eukaryote

Answer 10

cells that enclose DNA in nuclei, generally larger and more complex, newer, contain organelles, can be unicellular or multicellular

Question 11

protists

Answer 11

eukaryotes, normally unicellular, can be autotrophic or heterotrophic, some more animal like, some more plant like

Question 12

fungi

Answer 12

eukaryotes, have cell walls, mostly multicellular, heterotrophic, ex: mushroom, yeast

Question 13

plants

Answer 13

eukaryotes, autotrophs (photosynthesis), multicellular, cell walls of cellulose, chloroplasts

Question 14

animals

Answer 14

eukaryotes, heterotrophs, multicellular, no cell walls

Question 15

plant cell (difference from animal cell)

Answer 15

contain cell wall and chloroplasts, more rectangular and stiff, green

Question 16

animal cell (difference from plant cell)

Answer 16

contain centrioles and lysosomes, more round shape

Question 17

cell membrane

Answer 17

controls what enters and exits the cell, made of a phospholipid bilayer and proteins

Question 18

mitochondria

Answer 18

produces the energy a cell needs to carry out its functions

Question 19

lysosomes

Answer 19

uses chemicals to break down food and worn out cell parts, mostly in animal cells

Question 20

nucleus

Answer 20

control center of the cell, contains DNA

Question 21

golgi apparatus/golgi bodies

Answer 21

receives proteins and other materials from the ER to package and distribute

Question 22

vesicles

Answer 22

containers enclosed in a membrane that are used to transport molecules around the cell

Question 23

ribosomes

Answer 23

assembles amino acids into proteins

Question 24

cell wall

Answer 24

rigid outer layer, plant cells only

Question 25

centriole

Answer 25

help organize cell division, animal cells only

Question 26

endoplasmic reticulum

Answer 26

has passage ways that carry proteins and other materials from one part of the cell to another, rough ER contains ribosomes, smooth ER does not

Question 27

concentration gradient

Answer 27

difference of concentration of a solution

Question 28

active transport

Answer 28

process that moves materials across a cell membrane against a concentration gradient, requires transport protein and energy

Question 29

passive transport

Answer 29

movement of particles from a higher concentration area to a lower concentration area, no energy needed

Question 30

sodium-potassium pump

Answer 30

an example of a protein pump, uses ATP energy to take in sodium and pump out potassium, can only move Na and K

Question 31

diffusion

Answer 31

random movement of particles from high concentration to low concentration area

Question 32

simple diffusion

Answer 32

movement of particles from high concentration to low concentration through the bilayer of the membrane

Question 33

facilitated diffusion

Answer 33

requires a concentration gradient, particles move through a protein channel in the membrane from high concentration to low concentration

Question 34

osmosis

Answer 34

diffusion of water across a membrane in order to balance the concentration of substances in solution that cannot cross the membrane themselves, moves from low concentration of solute/high concentration of water to high concentration of solute/low concentration of water

Question 35

hypertonic

Answer 35

higher solute concentration, cell shrinks in this solution

Question 36

hypotonic

Answer 36

lower solute concentration, cell swells up in this solution

Question 37

isotonic

Answer 37

equal solute concentrations

Question 38

lipid bilayer

Answer 38

plasma membranes are made of two layers of phospholipids, the hydrophilic heads are on the outside and hydrophobic tails on the inside

Question 39

selectively permeable

Answer 39

some substances can cross over but others cannot, describes cell membranes

Question 40

endocytosis

Answer 40

membrane pinches in to form a vesicle for incoming material

Question 41

exocytosis

Answer 41

vesicles fuse with the cell membrane to release outgoing material

Question 42

aquaporins

Answer 42

proteins that allow water to pass through the cell membrane