Cell biology Flashcards
The cell theory says that all __ ___ are composed of cells, the cell is the basic ___ __ of life, the _____ _____ of life takes place inside the cell, cells only arise from ______ ____, and cells carry ____ ____ in the form of DNA which is passed from ___ to ____ cell
living things, functional unit, chemical reactions, pre-existing cells, genetic information, parent, daughter
The 6 kingdoms of life
bacteria, archaea, protista, fungi, plantae, animalia
The ___ __ ___ says that the cell membrane consists of a phospholipid bilayer that with proteins embedded throughout it than can move freely within the membrane
fluid mosaic model
The phospholipid bilayer is permeable to ___, _____ molecules like ___, and small ___ molecules like water. Small charged particles cross through __ _____, and larger charged molecules and ____ pass through by __ ____
small, nonpolar, oxygen, polar, protein channels, ions, carrier proteins
DNA is complexed with _____, which are structural _____. These _____ the DNA, and are also involved in regulation of __ ___. These together make _____
histones, proteins, compact, gene transcription, chromosomes
A dense structure in the nucleus where rRNA synthesis occurs
nucleolus
Ribosomes are the sites of __ __ and are synthesized by the ____. Free ribosomes are found in the ____, and bound ribosomes line the __ __ of the ___ ___
protein synthesis, nucleolus, cytoplasm, outer membrane, endoplasmic reticulum
The endoplasmic reticulum is involved in the ___ of materials throughout the cell, especially those destined to be ____ by it. The smooth ER does not contain ____, and is involved with ____ and production of ____. The ____ ER contains ribosomes and aids in __ ___
transport, secreted, ribosomes, metabolism, lipids, rough, protein production
The golgi apparatus receives ___ and their contents from the ___ __ and then modifies them via processes such as ____, repackages them into vesicles and distributes them to the cell surface for ____
vesicles, smooth ER, glycosylation, exocytosis
Mitochondria are the sites of __ __ within the cell and hence suppliers of ___, in the form of _____. Each mitochondrion is composed of an outer and inner ____ ____
aerobic respiration, energy, ATP, phospholipid bilayer
The cytoplasm includes the _____ (cellular fluid) and the _____. Transport within the cytoplasm occurs by _____
cytosol, organelles, cyclosis
vacuoles and vesicles are ______ ____ involved in the transport and ___ of materials that are ___, ___, ____, or ___ by the cell. Vacuoles are ____ than vesicles and are more likely to be found in ___ than ___ cells
membrane-bound sacs, storage, secreted, ingested, processed, digested, larger, plant, animal
Centrioles are composed of ____ and are involved in __ __ during cell division. They are not bound by a _____. Animal cells usually have a pair of centrioles oriented at __ ____ to each other that lie in a region called the _____. This region _____ microtubules and helps regulate the ____ of the cell cycle. ___ cells do not contain centrioles
microtubules, spindle organization, membrane, right angles, centrosome, organizes, progression, plant
lysosomes are membrane-bound ____ that contain __ ___ involved in intracellular ______. Lysosomes break down material ___ by the cell. A sick of dying cell may self-destruct by ____ the lysosome membrane and releasing its ____ ___. This process is called ____
vesicles, hydrolytic enzymes, digestion, ingested, rupturing, hydrolytic enzymes, autolysis
The cytoskeleton ___ the cell, maintains its ___ and aids in ___ ___. It is composed of ___, ___ and ___ ____.
supports, shape, cell motility, microtubules, microfilaments, intermediate filaments
microtubules are __ ___ made of up polymerized ___ that radiate throughout the cell and provide it with support. They provide a framework for __ ___ within the cell. ___ which direct the separation of chromosomes during cell division, are composed of microtubules. ___ and ___ are specialized ___ of microtubules that extend from certain cells and are involved in __ ___ and ___ ____
hollow rods, tubulin, organelle movement, centrioles, flagella, cilia, cell motility, cytoplasmic movement
Microfilaments are ___ rods of ____, which are important in cell movement as well as _____. ___ ___ is based on the interaction between actin with myosin. Microfilaments move materials across the plasma membrane, for example in the ____ __ of cell division and in ___ movement
solid, actin, support, muscle contraction, contraction, amoeboid
The net movement of dissolved particles from a region of higher to lower concentration that does not require energy
simple diffusion
When the cytoplasm of a cell has a lower solute concentration than the extracellular medium
hypertonic
when a cell is hypertonic, water flows ___ of a cell. This process is called ___ and causes a cell to ___
out, plasmolysis, shrivel
When the extracellular environment is less concentrated than the cytoplasm of the cell.
hypotonic
in a hypotonic cell, water will flow ___ the cell, and cause it to ___ (burst). For example, ____ ___ cells will burst if placed in distilled water, and freshwater protozoa have __ ___ to pump out excess water and prevent bursting
into, lyse, red blood, contractile vacuoles
When extracellular environment has the same concentration of solutes as the cell cytoplasm and water moves back and forth in equal amounts
isotonic
The net passive movement of dissolved particles down their concentration gradient through special channels or carrier proteins in the cell membrane; does not require energy
facillitated diffusion
the net movement of dissolved particles against their concentration gradients with the help of transport proteins; requires energy
active transport
Carrier molecules aid in the regulation of the cell’s internal content of ___ and ___ molecules. ____ move two or more ions or molecules in the same direction across the membrane. _____ exchange one or more ions (or molecules) for another ion or molecule across the membrane. ____ are energy dependent carriers requiring ____.
ions, large, symporters, antiporters, pumps, ATP
A processes in which the cell membrane invaginates, forming a vesicle that contains extracellular medium and allows the cell to bring large amounts of extracellular material inside the cell
endocytosis
The ingestion of fluids or small particles
pinocytosis
the engulfing of large particles, often binding to membrane receptors before being engulfed
phagocytosis
When a vesicle within the cell fuses with the cell membrane and releases a large volume of contents to the outside
exocytosis
exocytosis can play an important role in ___ __ and ___ ___ (e.g. neurotransmitters)
cellular growth, intercellular signalling
In both endocytosis and exocytosis, material never passes through the ___ __
cell membrane
when kinetic energy spreads small suspended particles throughout the cytoplasm of the cell
brownian movement
When the circular motion of the cytoplasm around the cell transports molecules
cyclosis / streaming
The ER forms a network of ___ throughout the cytoplasm and provides a ___, ____ passageway from the plasma membrane to the ____ ____
channels, direct, continuous, nuclear membrane
____ can serve as a sufficient means of transport for ___ and ___ from the environment to the cells, if the cells are in direct or ___ contact with the external environment. In larger, more complex animals, diffusion is important for the transport of materials between cells and ______ ____ that bathes the cells
diffusion, food, oxygen, close, interstitial fluid
In complex animals whose cells are too far from the external environment, the ___ ____ transports materials by its ____ which transports fluids, and _____, which drives circulation
circulatory system, vessels, pumps
For ____ organisms, cell division is a means of reproduction, whereas for multicellular organisms, it is a method of ___, ___ and ___ of worn out cells.
unicellular, growth, development, replacement
Interphase is a period of ___ and ____ ___. A cell spends ____% of its life in interphase. During this period, the cells performs its normal ____ functions, and each chromosome is replicated so that during each division, a ___ __ of the ___ can be distributed to both daughter cells. After replication, the chromosomes consist of two identical ___ ___ held together at the central region called a ____. During interphase, the individual chromosomes are __ ____. The DNA is instead ___ and called ____.
growth, chromosome replication, 90, cellular, complete copy, genome, sister chromatids, centromere, not visible, uncoiled, chromatin
The ___ phase initiates interphase and is an __ ___ phase. It varies in ___, and this determines the length of the entire __ ___. The cell increases in ___ and synthesizes ____.
G1, active growth, length, cell cycle, size, proteins
The ___ phase is the period of DNA synthesis
S
The ____ phase is the phase where the cell prepares to _____. It grows and synthesizes ___
G2, divide, proteins
___ and ___ are part of the M phase of mitosis and are the ___ phase of the cell cycle
mitosis, meiosis, last
In mitosis, the two daughter cells receives a ___ __ of the original genome. This type of cell division occurs in ___ cells. ____ __ is followed by cell division
complete copy, somatic, nuclear division
nuclear division
karyokinesis
cell division
cytokinesis
The phase where chromosomes ____. Centriole pairs _____ and move toward the opposite ___ of the cell. The ___ ___ forms between them and the nuclear membrane ____, allowing the spindle fibers to interact with the chromosomes
condense, separate, poles, spindle apparatus, dissolves
in metaphase, the centriole pairs are now at the opposite poles of the cell. The fibres of the spindle apparatus attach to each ____ at its corresponding _____, protein location on the centromere. The spindle fibres align the chromosomes at the -__ of the cell forming the ___ ___
chromatid, kinetochore, equator, metaphase plate
In anaphase, the _____ split so that each chromatid has its own distinct one, and allowing sister chromatids to ____. The sister chromatids are pulled towards the opposite poles of the cell by the ____ of the spindle fibers.
centromeres, separate, shortening
In telophase, the spindle apparatus ___, and a ___ ___ forms around each set of newly formed chromosomes. Thus, each nucleus contains the ___ number as the parent nucleus. The chromosomes ___, resuming their interphase form.
disappears, nuclear membrane, diploid, uncoil
In cytokinesis, which is near the end of ___, the ___ divides into two daughter cells, each with a complete ___ and its own set of ___. In animal cells, a ___ __ forms and the cell membrane indents along the ___ of the cell, eventually pinching through the cell and separating the two nuclei. In plant cells, a ___ ___ forms between the two nuclei, effectively splitting the plant cell in ___ and allowing the cell to divide
telophase, cytoplasm, nucleus, organelles, cleavage furrow, equator, cell wall, half
Sexual reproduction have two ___ involved, and occurs via the fusion of two ____. Meiosis is the process by which these ___ ___ are produced. Meiosis produces ____ cells, halving the number of chromosomes. It involves two divisions of ___ __ ___, resulting in ___ haploid cells called gametes.
parents, gametes, sex cells, haploid, primary sex cells, 4
In prophase 1 of meiosis, the chromatin condenses into chromosomes, the ___ __ forms, and the ___ and __ ____ disappear. _____ ____ come together and intertwine in a process called ____.
spindle apparatus, nucleoli, nuclear membrane, homologous chromosomes, synapsis
When a pair of homologous contains contains 4 chromatids and is therefore called a ___
tetrad
Chromosomes that code for the same traits, one inherited from each parent
homologous chromosomes
When periodically, chromatids of homologous chromosomes break at corresponding points and exchange equivalent pieces of DNA
crossing over
The points of contact between homologous chromosomes where crossing over can occur
chiasmata
_____ among chromosomes through crossing over, results in increased __ ___ within a species, and produces 2 ____ sister chromatids
recombination, genetic diversity, non-identical
In metaphase I, homologous pairs align at the __ __ and each pair attaches to a separate __ ___ at the ____
equatorial plane, spindle fiber, kinetochore
In anaphase I, the homologous pairs separate and are pulled to opposite ___ of the cell. This process is called ___. During this process, each chromosome of ___ origin separates from its homologue of ___ origin, and either chromosome can end up in either daughter cell. Thus, the distribution of ___ ___ to two intermediate daughter cells is ____ with respect to parental origin. Each daughter cell will have a unique ___ of genes from a random mixture of ___ and ____ origin.
poles, disjunction, paternal, maternal, homologous chromosomes, random, combination, paternal, maternal
____ occurs when cells do not separate appropriately during meiosis. This results in the daughter cell having an ___ number of chromosomes
nondisjunction, incorrect
In telophase 1, a __ ___ forms around each new nucleus, and at this point, each chromosomes still consists of ____ ____ joined at the centromere.
nuclear membrane, sister chromatids
The second meiotic division is similar to mitosis, but is not preceded by ___ ___. The chromosomes align at the ____, separate, and move to ___ ___ and are surrounded by a re-formed nuclear membrane. The new cells have the ____ number of chromosomes. In women, only ___ of these daughter cells becomes a __ ___, while the other two or three cells are ___ by the body
chromosomal replication, equator, opposite poles, haploid, 1, functional gamete, destroyed
