Chapter 4: A Tour Of The Cell Flashcards
How are eukaryotic cells different from prokaryotic cells?
They have membrane bound organelles and a nucleus
Cell theory
The theory that all living things are composed of cells no that all cells come from other cells
What is an organelle?
A membrane-enclosed structure with a specialized function within a eukaryotic cell
What is a nucleus?
The genetic control center of a eukaryotic cell
What is the location and function of a cell’s nucleus?
Located inside the nuclear membrane; genetic control center of a cell
What is the function of the nucleolus?
Produces the components or ribosomes
Chromosomes
S: Made of DNA and proteins threadlike strands, chromatin = tangles chromosomes
F: controls how the cell forms and how the cell woks (directs all cell activity); hereditary information- determines all traits in cells and in organisms; humans have 46 chromosomes
Nucleolus
S: granule
F: makes ribosomes; cells involved in cell division
Nuclear membrane
S: made of proteins and phospholipids; thin, flexible, porous (larger pores than cell membrane’s)
F: controls what enters and exits the cell’s nucleus
Nucleoplasm
S: very thick fluid; mostly water, many solutes (amino acids, sugars, salt, minerals…)
F: circulate materials through the nucleus
Cell membrane (plasma membrane)
S: made of proteins and phospholipids; thin, flexible, porous
F: controls what enters and leaves the cell
Cytoplasm (cytosol)
S: thick fluid; mostly water, many solutes (sugars, salts, amino acids, minerals…)
F: circulates materials within the cell
Mitochondria
S: rod-shaped, peanut-shaped; double membrane - inner folded membrane (folds = christae)
F: releases energy for cell activity; “powerhouses”, where cellular respiration happens
Ribosomes
S: very tiny granules made of protein + RNA, NOT membrane-bound
F: “protein factories”- where proteins are made
Endoplasmic reticulum
S: network of double membranes extending through cytoplasm
F: passageway for materials to move from place to place in the cell; rough ER has ribosomes attatched; smooth ER has no ribosomes attatched (makes phospholipids)
Golgi apparatus
S: stack of flattened sacs
F: active in secretion of materials -> forming, assembling, and packaging useful materials to be released from the cell to be used outside the cell (Golgi are very abundant in cells of glands - such as salivary glands…)
Vacuoles
(Usually larger and more abundant in plant cells than in animal cells) S: surrounded by a single membrane, fluid filled - mostly water, many possible solutes
F: storage of water of variety of other materials (such as water-soluble pigments in plant cells)
Cytoskeleton
S: network of microtubules + microfilaments; mostly made of proteins; microtubules - hollow, tubelike; microfilaments - fine threads, smaller than microtubules
F: support and give shape - especially in animal cells; help move materials…
Centrioles
Pair of structures near the nucleus in animals cells;
S: made of microtubules mostly
F: used in animal cell division
Lysosomes
Are more common in animal cells than plant cells;
S: small, spherical-egg-shaped; contains enzymes that digest materials (esp. Proteins)
F: digest materials (esp. Proteins), destroy foreign “invaders”, worn out cell parts, “suicide sacks”
Cell wall
Surrounds cell membrane of ALL plant cells; never part animal cells. NOT part of the “living material” in the plant cell;
S: thick, mostly cellulose, also pectin and lignin;
F: support the plant cell and give shape…
Plastids
In cytoplasm of some PLANT cells;
Includes: chloroplasts, chromosplasts, leuvoplasts
Chloroplasts
S: spherical-egg-shaped; contains much chlorophyll and other enzymes…
F: photosynthesis - captures light energy… Makes glucose
Chromosplasts
Contain pigments other than chlorophyll
Leucoplasts
“Starch grains” - story starch, contain NO pigments
Cilia/Flagella
Extend through cell membrane to outside of cells
S: made of microtubules
F: used in cell movement; flagella are much thicker than flagella
