BIOL 1120 - LAB 3 Flashcards
1
Q
what is a cell membrane?
A
- boundaries of the cell
- controls the passage of the materials into and out of the cells
2
Q
what is a nucleus?
A
- large organelle IN the cell
- contains thread-like matter called chromatin which contains DNA and protein
3
Q
what is a cytoplasm?
A
- all contents of a cell except the nucleus
- cytosol is the liquid component of cytoplasm that surrounds the organelles
4
Q
what is a nucleolus?
A
- dark mass found in the nucleus
- where ribosomes are produced
5
Q
what is the nuclear membrane/envelope?
A
- composed of a double layer membrane that are held together at nuclear pores
- separates the contents of the nucleus from the rest of the cell
6
Q
what are ribosomes?
A
- small, dark granules composed of protein and RNA
- found free in the cytosol
- also found on the surface of the rough endoplasmic reticulum
- responsible for interpreting the genetic code and synthesizing polypeptides (amino acid protein chain)
7
Q
what is the ROUGH endoplasmic reticulum?
A
- network of flattened sacs that are connected to each other
- sacs are called CISTERNAE
- called “rough” b/c it is covered in ribosomes
- make proteins and produce cell membranes
8
Q
what is the SMOOTH endoplasmic reticulum
A
- network of linked membrane-enclosed sacs
- differs from rough ER in that the cisternae are more tubular and branch more extensively
- lacks ribosomes (thats why called “smooth”)
- lipid synthesis
- stores calcium ions
- involved in the detoxification of drugs
9
Q
what is the golgi apparatus?
A
- synthesizes carbohydrates and adds these to proteins that have been synthesized in rough ER
- packages these modified proteins inside golgi vesicles
10
Q
what is the mitochondria?
A
- have a double layer membrane
- inner membrane contains folds called cristae
- generate most of the chemical energy needed to power the cells biochemical reactions
- reproduce independently of the cell and live for 10 days
11
Q
what is a cristae?
A
- folds in the inner membrane of mitochondria -space b/w the cristae is called the matrix
- enzymes on the cristae synthesize ATP from energy extracted from organic compounds
- folds increase surface area
- increased surface area allows mitochondria to produce more energy at a faster rate
12
Q
what are lysosomes?
A
- packages of enzymes (proteins) enclosed in a single unit membrane and can vary in shape
- break down different molecules
- digest worn-out organelles
- involved in programmed cell death
- in liver cells, break down glycogen
13
Q
what are exocytotic vesicles?
A
- type of vesicle involved in vesicular transport
- releasing waste and large molecules from the cytoplasm to the outside of the cell
14
Q
what is endocytosis?
A
- type of vesicular transport that moves substances INTO the cell
- cells take in substances from outside of cell by engulfing then in a vesicle
15
Q
what is an endocytotic vesicle?
A
- formed during endocytosis
- cells ingest fluid, molecules, and particles by endocytosis and forms vesicles that moves them into the cell
16
Q
what is glycogen?
A
- stored form of glucose
- made up of connected glucose molecules
- glucose is our body’s main source of energy
17
Q
what is the brush border?
A
- inner edge of the tissue
- dense covering of microvilli
- specialize in absorption
18
Q
what are microvilli?
A
- extensions of the plasma membrane of cells
- contains protein filaments, made of actin, attaching from the tip to the base
- increase the surface area of the cell membrane
19
Q
what are goblet cells?
A
- secretes materials necessary for digestive processes
- found in small intestines
- produce mucin that serves for digestion
- create a protective mucus layer and lubricates the surface of intestines
20
Q
what are desmosomes?
A
- pin adjacent cells together, ensuring that cells in organs and tissues that stretch (like skin and cardiac muscle), remain connected in an unbroken sheet
- found in epithelial tissues ex. stratified squamous epithelium
21
Q
what are cilia?
A
- hair-like processes found on the surface of some animal cells
- found on cells in the respiratory tract and uterine tubes
- function to move mucus
22
Q
what are intercalated discs?
A
- responsible for connecting cardiac muscles, allowing them to contract in unison as a single functional unit
23
Q
what are gap junctions?
A
- joining cells that allow material to pass directly from one cell to the next, since they contain pores that allow transit
- in cardiac muscles, they are important for the transmission of the electrical signals that provide a coordinated heart beat
24
Q
what is an extracellular matrix?
A
- helps cells attach to, and communicate with, nearby cells
plays an important role in cell growth, cell movement, and other cell functions - involved in repairing damaged tissue
25
Q
what is cytoskeleton?
A
- collection of filaments and tubules that provide internal support and movement of the cell
- composed of microfilaments, intermediate filaments, and microtubules
26
Q
what is flagella?
A
- single, long, whip-like structures
- they whip around and sometimes twirl, pushing the cell along
- produced from the cytoskeleton
- energy to move them is provided by mitochondria
27
Q
what is mitotic spindle?
A
- structure that forms during cell division and separates duplicated chromosomes
- in other words, used to direct movement of the chromosomes during cell division
28
Q
what are centrioles?
A
- help to control and regulate activity of the cytoskeleton
- spindle formation during cell division
- made of microtubules
- short, cylindrical assemblies of microtubules
- help determine the locations of the nucleus and other organelles within the cell
29
Q
what are asters?
A
- cellular structure shaped like a star
- formed around each centrosome during mitosis in animal cells
