Lab 3 Flashcards
What is a solvent?
a liquid that has dissolved or can dissolve one or more solutes
What is a solute?
a substance that is dissolved in a liquid (solvent)
What is a solution?
a liquid (solvent) and it’s solvents
What are 2 passive transport types?
- osmosis
2. diffusion
What is osmosis?
the movement of a solvent (usually water) through a selectively permeable membrane from an area of low concentration to an area of high concentration.
What is diffusion?
the random movement of molecules from an area of high concentration to an area of low concentration.
What cellular structure is selectively permeable in plant and animal cells?
cell membrane
What does isotonic mean?
concentration on the outside is the same as the concentration on the outside.
What does hypertonic mean?
concentration in the cell is higher than the environment. the cell is hypertonic to the environment.
What does hypotonic mean?
The cell has a higher concentration than the environment so the environment is hypotonic to the cell.
What cellular structure prevents plants from taking up too much water?
the cell wall.
What is the formula to find percent change in weight?
(final weight - initial weight )
______________________
initial weight
Are concentrations of solutes usually higher or lower inside the cell?
higher.
What is turgor pressure?
the force of the plasma membrane pushing outwards due to the central vacuole increasing in volume.
What is plasmolysis?
when the plasma membrane pulls away from cell wall.
How do prokaryotes divide?
binary fission.
How do eukaryotes divide?
mitosis and cytokinesis.
What are major functions of mitosis?
- production and maintenance of multicellularity
- asexual reproduction
- replacement of old or damaged cells
What is are chromosomes made of?
DNA and proteins
What is the longest phase of the cell cycle?
interphase.
What is mitosis?
the division of the nucleus, resulting in the formation of two genetically identical daughter nuclei.
What is cytokinesis?
the division of the cytoplasm between the two resulting daughter cells.
What is the G1 stage of the cell cycle?
CELL GROWTH
-new organelles and proteins are synthesized and the plasma membrane increases in size.
What is the S stage of the cell cycle?
DNA SYNTHESIS
-each chromosome produces an exact copy of itself by DNA replication
What is the G2 stage of the cell cycle?
CELL GROWTH
-a second period of cell growth and final preparations for division
What are the stages of mitosis?
prophase, prometaphase, metaphase, anaphase, telophase (and then cytokinesis).
What happens in prophase?
- replicated chromosomes condense
- spindle microtubules begin to form and move to opposite ends of the cell
What happens in prometaphase?
- nuclear envelope breaks down
- spindle microtubules grow and attach to the centromeres of the replicated chromosomes
What happens in metaphase?
- spindle apparatus is completely formed
- replicated chromosomes line up along the mid region (the cell plate)
What happens in anaphase?
- centromeres of each replicated chromosome separate
- single chromosomes are pulled by their centromeres to opposite poles
What happens in telophase of a plant cell?
- single chromosomes go to poles and begin to uncoil
- nuclear envelopes begin to form around the groups of chromosomes
- cytokinesis starts (call plate forms and grows outward to form 2 daughter cells)
What happens in telophase of animal cells?
-single chromosomes arrive at the poles and begin to uncoil
What is the formula to find the amount of time spent in each stage of mitosis?
(# of cells in phase / grand total) x 960 minutes
What is a colony?
a group of individual cells or organisms that adhere and communicate with eachother.
What were the three steps of multicellularity?
unicellular –> colonial forms –> multicellular organisms
What are multicellular organisms?
single organisms that have specialized cells
What does the eyespot do? What color is it?
orients the organism towards light. it is red
What is a pyrenoid?
it is responsible for synthesizing starch from sugars produced by photosynthesis
What is the purpose of a gelatinous matrix?
it holds the cells together as a colony
How do adjacent cells communicate with each other?
cytoplasmic bridges
is there division of labor among cells?
no.
What are some differences between unicellular, colonial, and multicellular organisms?
uni - multiple organisms col - divide by mitosis - daughter cells stay stuck together multi- single organisms with specialized cells
Are the resulting cells of binary fission identical or different?
identical.