Multicellular organism consists of many cells which must be stuck together but at the same time allow for communication between the cytoplasm of two cells. Read the pages indicated by B-6 in the text and study behavioral objective 5. Since plant cells have a cell wall surrounding the protoplasm they contain channels from one cell to another called plasmodesmata. The outer part of the cell walls of two cells are pasted together by a sticky substance called pectin. In your notes draw two plant cells with thick cell walls and a plasmodesmata. Draw the figure in a manner that the cytoplasm of one cell is connected
to the cytoplasm of the second cell (cytoplasmic bridge).
Animal cells are held together by desmosomes, tight junctions, and gap junctions. Study behavioral objectives 5 and 6 and read the pages indicated by B-6. These structures all consist of protein. In your notes draw figures showing these three types of connections found in animal cells and write a paragraph contrasting between them.
17. Press here to check answer. press
18. Match the connection types listed below to the statement
which describes a
function in living cells
A. plasmodesmata
B. gap junction C. tight junction
D. desmosome
1. Structures consisting
of cell membrane strands through pores of a
cellulose sheet.
2. Small protein filaments
which extend into cytoplasm of both cells to firmly
attach the cells together.
3. Strands of protein which
stick cells together and seal the outside to
prevent leakage.
4. Proteins which extend
through the membrane of two cells holding them
together with a channel in the center allowing material to move from
one
cell to another.
1
2
3
4
a) A
D
C
B
b) A
C
B
D
c) B
D
A
C
d) D
A
C
B
e) B
D
C
A
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19. Compare and contrast between gap junction and plasmodesmata.
a)
Gap junctions consist of openings through proteins of adjacent
membranes and plasmodesmata are openings through cellulose
walls.
b) Gap junctions consist of openings through cellulose and plasmodesmata
consist of openings through cell membranes.
c) Gap junctions hold plant cells together and plasmodesmata allow animal
cells to communicate by connecting adjacent cytoplasm..
d) Gap junctions are solid protein structures holding animal cells
together
and plasmodesmata are openings through cellulose walls..
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