UNIT 2: Cells Flashcards
1
Q
Cilia
A
- Move microbes and debris up and out of the airways
- Present in eukaryotes
2
Q
Lysosome
A
- Formed by budding from golgi apparatus
- “garbage collecters” of the cell; take in damaged or worn our cell parts
- Break down the cells with the enzymes inside of them
3
Q
Centrioles
A
- Organizing microtubules that serve as the cell’s skeletal system
- They help determine the locations of the nucleus and other organelles within the cell
4
Q
Microtubules
A
- Organize positions of organelles, direct intra cellular transport
- linear polymers of tubulin dimers (alpha and beta tubulin)
- provide tracks along which vesicles and organelles move between the cell interior and the plasma membrane
- motor proteins travel along microtubules
(dyneins and kinesins) - Microtubules separate and move chromosomes during cell division, and move some eukaryotic cells themselves
- Act against compression
- 9 + 2 complex
5
Q
Golgi Apparatus
A
- Prepares proteins and lipid molecules for use in other places inside and outside the cell
- Customize proteins into forms in which the body can use; may add on lipids or carbs
- Synthesizes glycolipids and sphingomyelin
- Transports materials to destination; plasma membrane in secretory vesicles that release by exocytosis
6
Q
Smooth ER
A
- Synthesizes lipids, phospholipids as in plasma membranes, and steroids
- Synthesized materials leave the smooth ER in vesicles and are transported to the golgi body
- Stores calcium
- Rich in enzymes
- Detoxifies chemicals
- Mobilizes glucose from stored
glycogen in the liver
7
Q
Rough ER
A
- Synthesizes proteins from ribosomes on outside
- Production, folding, quality control and dispatch of some proteins
- Proteins and other materials leave rough ER in vesicles which get sent to the golgi body
8
Q
Mitochondrion
A
- Provides energy for cell functions (active transport ect)
- During cellular respiration, it generates ATP
- Cells that need more energy have more mitochondria
- Runs on glucose
9
Q
Cell Membrane
A
- Regulates the transport of materials entering and exiting the cell
- Volume is important
10
Q
Cell Wall
A
- Provide structural strength and support
- Semi-permeable surface for molecules to pass in and out of the cell
- Animal cells do not have one
11
Q
Cytoplasm
A
Provides a platform upon which other organelles can operate within the cell
12
Q
Nucleus
A
- Contains genetic material (DNA) which dictates what the cell is going to do and how
- Has a nuclear membrane that is a double layer that encloses nucleus and separates chromosomes from cytoplasm
- Chromatin is the tangled, spread out form of DNA inside nuclear membrane
- When the cell is ready to divide, the chromatin (DNA) condenses into chromosomes
- Nucleus contains a nucleolus where ribosomes are made
- Nucleopores
13
Q
Chromatin
A
- Cell processes including DNA replication, transcription, DNA repair, genetic recombination, and cell division
- Found inside the nuclear membrane
- When cell is ready to divide it condenses into chromosomes
14
Q
Ribosomes
A
- RNA protein complexes composed of a large and small sub unit
- NOT organelles as they are not membrane enclosed
- Once it leaves the nucleus, it has a job of synthesizing protein
- Either attaches to rough ER (membrane bound ribosomes)or floats in cytoplasm (free ribosomes) depends on mRNA message
- Reads the messenger RNA (mRNA) sequence and translates that genetic code into a specified string of amino acids, which grow into long chains that fold to form proteins
15
Q
Nuclear Membrane
A
- Acts as a barrier that separates the contents of the nucleus from the cytoplasm
- Phospholipid bilayers, which are permeable only to small nonpolar molecules
- Contains chromatids
16
Q
What do all cells have in common?
A
Cell membrane, cytoplasm and DNA (genetic material
17
Q
What are the two categories of cells?
A
- Prokaryotic (archae & bacteria)
- Eukaryotic (protists, animals, plants, fungi)
18
Q
Prokaryotic cells
A
- Unicellular (single celled)
- No membrane bound organelles
- Singular circular DNA is found in a region of space called nucleoid
- Smaller in size which allows them to reproduce fast and efficiently
- Cell wall is made of peptidoglycan (bacteria) or psuedopeptidoglycan (archae)
19
Q
Eukaryotic cells
A
- Multicellular
- Larger in size
- Membrane bound organelles with a “true” nucleus
- Linear chromosomes
20
Q
Endoplasmic reticulum
A
- Membrane enclosed passage for transporting materials
- Includes tubules and internal spaces (cisternae)
- Continuous with the nuclear envelope
21
Q
Vacuoles
A
- Sac like structures that stores different materials
- Help sequester waste product
- Help maintain water balance in plant cells (large vacuole)
22
Q
Structure of the mitochondria
A
- Two membranes; a smooth outer membrane and a highly folded inner membrane
- Folds (cristae) increase surface area for membrane proteins
- Intermembrane space (space between inner membrane and outer membrane) holds protons (low pH)
- The mitochondrial matrix is a fluid-filled space inside the inner membrane
23
Q
Free ribosomes
A
- Ribosomes that are floating in the cytosol
- Synthesize proteins that function in the cytosol
- The synthesized “free proteins” can remain in cytosol, pass into nucleus, become a part of mitochondria, chloroplasts, cytoskeleton ect
24
Q
Endomembrane system
A
- Compartmentalizes the cell, channelling passage of molecules through cell’s interior
- Plays a key role in synthesis and hydrolysis
25
Q
Cytoskeleton
A
- Maintains shape of cell
- Includes thread like microfilaments which are made of proteins, microtubules and intermediate filaments
26
Q
Chloroplasts
A
- Type of plastid
- Organisms that are photoautotrophic (need sun for energy)
- The chloroplast produces sugar via photosynthesis
- Green because of pigment chlorophyll which absorbs light energy
- Move glucose by light energy (photosynthesis)
- Synthesize new organic compounds from CO2 and H2O
- Convert solar energy to chemical energy
27
Q
Flagella
A
- Some bacteria have it
- Tail that helps it move and propel itself
28
Q
Homeostasis
A
Maintains temperature within the cell
29
Q
Cholesteral
A
- Good in membranes
- If temp drops cholesterol becomes “spacers” between phospholipids, preventing them from being to packed
- It can connect phospholipids to prevent them from being to fluid in warm temperatures
30
Q
Endosymbiotic organelles
A
- Mitochondria and chloroplasts are semi-autonomous
- Their proteins come primarily from free ribosomes in the cytosol
- Both mitochondria and chloroplasts have small quantities of DNA
- Mitochondria and chloroplasts grow and reproduce almost like bacteria
31
Q
Plastids
A
- Amyloplasts; store starch
- Chromoplasts; stores pigments
- Chloroplasts; harness solar energy
32
Q
Chloroplast anatomy
A
- Two membranes; inner membrane and outer membrane that surrounds the stroma
- Stroma houses the third membrane organized into sacs
- The stroma contains DNA, ribosomes,
and photosynthetic enzymes - Thylakoids hollow discs stacked into grana and hold chlorophyll
- Thylakoid membranes surround the thylakoid space
33
Q
Microfilaments
A
- Thin protein fibres assembled from actin sub units
- Have structural and locomotor functions; divide the cytoplasm, support tension, cell movement (myosin), Components of contractile elements in muscle fibres
34
Q
Intermediate filaments
A
- Provide structural support in many cells and tissues
- tissue-specific in their protein composition
- Provide mechanical support
- Withstand mechanical stress
- Cross link microfilaments or microtubules
