Week 2,3 Flashcards
What are the main components of the cytoskeleton?
Microtubules and actin filaments
What do microtubules consist of?
Protofilaments built from tubulin dimers (alpha and beta tubulin)
How many protofilaments around a hollow core make a microtubule?
13
What do the plus end and minus end do in a microtubule?
The plus end allows for expansion and the minus end does not expand
How do microtubules help cell wall growth?
By directing Golgi vesicles towards the membrane
How are microtubules important for functioning cilia and flagella?
They form the basis of cilia and flagella and as pairs slide past one another, it creates movement
What are microfilaments made of?
Actin monomers
Microfilaments are bigger or smaller than microtubules?
Smaller, but also polar
What are the organelles within a cell?
Vacuole, nucleus, endosymbionts (Plastids and Mitochondria), ribosomes, endoplasmic reticulum (smooth and rough) and the golgi apparatus
What is a tonoplast?
The membrane that surrounds a vacuole
What is in the vacuole?
Contains dissolved ions, organic acids, and other acidic substances
What is chromatin within a nucleus?
Combination of DNA and histone proteins
What does the nucleolus do?
Transcribes ribosomal RNA and combines it with proteins to form ribosomal large and small subunits
What is a chloroplast?
A plastid (symbiont) that performs photosynthesis within a plant cell
What is a leucoplast?
Colorless plastids that store starch (amyloplasts), lipids (elaioplasts), and proteins (proteinoplasts) but can also synthesize fatty acids, amino acids, and other compounds
What does a chromoplast do?
Synthesizes and stores non-chlorophyll pigments to attract seed-spreaders
What is a plastid called that has yet to take form?
Proplastid
How many genes are in the plastid genome?
About 100
What do mitochondria do?
They respirate, or release energy from sugars and store them as ATP
What is a peroxisome?
A self-replicating organelle that participates in photorespiration
What is photorespiration?
A detoxification process that removes built up toxic compounds
What do ribosomes do?
Synthesize proteins
Where do ribosomes come from?
Partly from the nucleolus and are finished building outside the nucleus
What does the endoplasmic reticulum do?
It is an intracellular communications system that functions by storing and releasing calcium and synthesizes lipids
What is a plasmodesmata?
ER-lined pores that connect to cytoplasms of adjacent cells
What is the golgi apparatus?
A collection of flat, membranous sacs that serves as a packing center (like for cell wall components)
Where do photosynthetic light reactions occur?
Thylakoid membranes
Where do photosynthetic “dark” reactions occur?
Stroma
What is a haploid?
A cell with one set of chromosomes (Gametes)
What is a diploid?
A cell with two sets of chromosomes (zygote)
What is a polypoid?
Cells with more than two sets of chromosomes
What is alternation of generations?
Life cycle involving sexual reproduction alternating between diploid sporophyte phase and haploid gametophyte phase
Where do sporophytes develop from?
Zygotes
What do sporophytes produce?
Sporocytes
What do sporocytes do?
Undergo meiosis to produce 4 haploid spores.
Where do gametophytes develop from?
Spores
What do spores do?
Form cells/sexual structure in which gametes are formed by mitosis
What is fertilization?
The fusion of gametes
How many daughter cells in mitosis?
Two that are identical
How many daughter cells in meiosis?
Four daughter cells after two successive divisions
In what group of plants are you most likely to find scattered vascular bundles in the stem?
Monocots
What type of lateral meristem is involved in the production of secondary tissue of xylem and phloem?
Vascular cambium
What type of meristem is found only in monocots and allows for cell division in the vicinity of the nodes and adds to stem length?
Intercalary meristem
What type of tissue is composed of thin, pliable living cells?
Parenchyma
What type of tissue consists of parenchymatous cells with extensive air spaces and is a common adaptation to aquatic environments?
Aerenchyma
What type of tissue consists of thickened secondary cell walls?
Sclerenchyma
What term is given to the embryonic (seed) root?
Radicle
What type of root does not develop from another root, but instead from a stem?
Adventitious root
What region of the root is composed of an apical meristem?
Region of cell division
From what tissue in the root does a root branch originate?
Pericycle
What group of plants exclusively produces adventitious and fibrous roots?
Monocots
What term is given to trees?
Arboral
What term is given to the embryonic (seed) root?
Radicle
What type of root does not develop from another root, but instead from a stem?
Adventitious root
From what tissue in the root does a root branch originate?
Pericycle
What group of plants exclusively produces adventitious and fibrous roots?
Monocots
Monocots
What term is given to trees or shrubs that lose their leaves during a dormancy period?
Deciduous
Deciduous
What function does a lenticel perform?
Gas exchange
Gas exchange
In what group of plants might you find a siphonostele?
Ferns
What group of plants lacks vascular tissue?
Bryophytes
What groups of plants cannot produce lateral (secondary) growth?
Monocots, ferns, lycophytes, and bryophytes
Why is lateral growth not possible in monocot stems?
There is no vascular cambium
