Exam 1 Review Flashcards
What are the requirements to be an organism
must be composed of one or more cells
Cell Theory
life is totally cellular
What are the requirements to be a cell
-plasma membrane made of lipids and protein.
-information flow is DNA to RNA to protein
-have enzymes needed to maintain themselves and, in many cases, grow and divide to produce more cells
DNA to RNA is
transcription
RNA to protein is
translation
translation occurs by
ribosomes
All cells come from _____
previously existing cells
All cells/organisms are related to the
original cell
all cells share common mechanisms for ______ and _______
maintenance and reproduction
what you learn from one cell can help you understand _____
others
Cells vary in ____ and ______
structure and machinery
cells can range from _____ to a _____
2 micrometers (bacteria) to a meter (giant squid neuron)
bacterial –
prokaryotic
Archaeon –
prokaryotic but with many processes related to eukaryotic cells
eukaryotic –
focus of most details covered in BIO 315
Cells vary in how they ____
function
Single-celled organisms
the cell IS the organism
there are many different types of single celled organisms such as
prokaryotes and eukaryotes
Multicellular organisms –
cells within a single individual can differ structurally and functionally
Cells are organized in _____ of different types. For example, _____
tissues, muscle
different cell types in one individual have the same _____ but ______ different _____ of genes
genes, express, subsets
(aka same DNA, different proteins)
How to study Cell Biology
- Microscopes
- other experimental approaches used in cell biology
Light microscopes are either ___ or _____
simple, compound
A simple light microscope has ___ lens
one
A compound light microscope has ___ lens
two or more
Advantages of light microscopes
less sample preparation needed (can be living cells)
Disadvantages of light microcopes
lower resolution and cells tend to be transparent
Resolution is
the ability to resolve two objects as different objects
What is the limit of resolution of light microscopes?
about 0.2 um – about 1/2 wavelength of visible light
Bright Field Microscopes
white light illumination
In bright field microscopes the cells are ____, so observation requires _____ _____
transparent, enhancing contrast
Bright field microscopes use ___ or ____ that differentially stain cellular components
dyes or stains
Bright field microscopes use ____ _____
special optics
Fluorescence microscopes make specific details within cells detectable using ______ _____
fluorescent molecules
Fluorescent microscopes ____ light or one wavelength and ____ at a ____ wavelength
absorb, emit, longer
____ microscopes and _____ _____ microscopes are both types of fluorescent microscopes
confocal, superresolution fluorescent
Confocal microscopes use ____ to ____ light scatter and ____ resolution, especially in _____ samples
lasers, decrease, increase, thicker
Superresolution fluorescent microscopes use multiple ____ to ____ resolution.
lasers, increase
Superresolution Fluorescent microscopes have an optical resolution of ____
20 nm (10 times smaller than light or fluorescent microscopes)
Electron Microscopes (EM) use _____ instead of visible light
electrons
Electron Microscopes have a _____ wavelength and a ____ higher resolution
smaller, higher
Electron microscopes have a resolution of ____
5 nm
Advantages of Electron microscopes
higher resolution (our concepts of sub-cellular structures is based on EM)
Disadvantages of electron microscopes
-extensive processing of samples required
-harsh fixation, staining with metals required
Types of electron microscopy:
X-ray crystallography and cyro-electron microscopy
X-ray crystallography and cyro-electron microscopy
detect individual atoms of biological molecules
Biochemistry
breaking tissue into cells and cells into component parts to study specific cells and specific sub-cellular components
Advantages of biochemistry
get details of the structure and function of cellular components
Disadvantages of biochemistry
lose information on the organization of these components
Genetics
taking advantages of genetic alterations that allow some components or processes in cells to be more easily studied
The study of human genetics _____ links ____/____/____ to specific cellular processes. EX: ____, ____, _____
diseases, genes, proteins, RNAs, sickle cell anemia, cystic fibrosis, albinism
You can use genetics for the ____ or _____ of ____ forms of other organisms
isolation, creation, mutant
Creating _____ ____ version of proteins to identify which ____/_____ type contain them and/or determine their specific ____ within cells
fluorescently tagged, cells/tissues, location
___ and ____ genes to study the _____ of the ____/____ they encode.
cloning, manipulating, function, proteins/RNAs
Example of cloning and manipulating genes: making specific ____ using _____/____ technology to mutate specific ____ to determine what goes wrong
mutations, CRISPR/Cas, genes
Example of cloning and manipulating genes: ____ experiments to identify the ____ in one organism that has the same _____ as one in the other
rescue, gene, function
the ___ gene that regulates ___ ____ was identified by finding the human gene that rescued a _____ cell division mutant (called ____)
human, cell division, yeast, cdc2
Eukaryotic cells have
multiple internal membrane-bound compartments (membrane bound organelles)
What are the two major compartments in eukaryotic cells?
nucleus and cytoplasm
Nucleus
bounded by a double membrane = nuclear envelope
Cytoplasm
everything inside the plasma membrane and outside the nucleus
Cytosol
fluid filled space outside the membrane
The particular model organism chosen depends on the ______
question
Bacteria are typically used to study…
basic genetic and molecular biology processes
The basic genetic and molecular biology processes include
the central dogma, nature of the gene, how food molecules are converted into energy and used as building blocks
Yeast are typically used to study….
the basic mechanisms common to eukaryotes
Yeast is the
eukaryotic bacterium
The basic mechanisms common to eukaryotes includes
cell division, structure and function of eukaryotic organelles, eukaryotic-gene structure and gene expression
Drosophila melanogoster and C. elegans are typically used to study
the basic process of cellular differentiation and animal development
Zebrafish are typically used to study
vertebrate development and regeneration
Mice are typically used to study
mammalian-specific process of development and physiology
Human cell cultures are typically used to study
specific cell types that can be cultured in vitro
Genetic material is contained in structures called
chromosomes
Chromosomes contain ____ and ____. This material is called ____
chromatin
The sequence of _____ in DNA contains the ____ _____.
nucleotides, genetic information
Different ____ contain different ____ ______
chromosomes, DNA sequences
A ___ is a ___ of genetic information
gene, unit
___ can code for ____ (___-____ ____) or ___ (___ ___)
genes, proteins, protein-coded genes, RNA, RNA genes
____ chromosomes contain more ___ than ___ chromosomes
larger, genes, smaller
The ___ and ____ modifications to those proteins organizes the ___ in ways that affect how the _____ ____ will be used
proteins, chemical, DNA, genetic information
DNA is composed of ____ strands of ______ ____ wound around each other in a _____ ____.
two, deoxyribonucleic acid, double helix
Each strand of DNA is a chain of ______, connected to each other by ______ bonds
deoxyribonucleotides, phosphodiester
Deoxyribonucleotides contain a ____ ____ that has a ____ group attached to the ___ sugar carbon and ____ ___, ____, _____, ____, or ____, to the ___ sugar carbon
deoxyribose sugar, phosphate, 5’, nitrogenous base, adenine (A), guanine (G), cytosine (C), thymine (T), `1’
The _____ in one DNA strand are all oriented in the ____ ____, which is determined by the __ and ___ sugar carbons.
nucleotides, same direction, 3’, 5’
The ___ group on the __ sugar carbon is attached to the ___ group on the ___ sugar carbon in what is called a _____ bond.
phosphate, 5’, hydroxyl, 3’, phosphodiester
The ___ of the nucleotides is one strand is ____ to the orientation in the other strands, so the strands are said to be _____ to each other, with one running __ to __ in one direction and the other running __ to __ in the opposite direction.
orientation, opposite, antiparallel, 5’, 3’, 5’, 3’
The two strands in DNA are bound together by ____ _____ between ____, with __ bonded to __ by ___ hydrogen bonds and __ bonded to __ by ___ hydrogen bonds.
hydrogen bonds, bases, A, T, two, G, C, three
The bonded bases, A with T and G with C, are called ___ ____
base pairs
Since AT base pairs only have two hydrogen bonds whereas GC base pairs have three, the two strands in DNA molecules that have a higher GC content are more _____ bound together than the strands with a lower GC content.
tightly
The number of DNA molecules per chromosomes is ____ at different stages of the ___ _____
different, cell cycle
The cell division cycle is a description of the events between the moment a cell is ____ through the time that the cell has ____, ___ its contents, and ____ to produce __ cells.
created, grown, doubled, divided, two
G1 phase
just born, DNA content not duplicated (unreplicated chromosome)
S phase
DNA is being actively replicated
G2 Phase
DNA has been replicated, cells readying for cell division (replicated chromosome)
M phase
replicated chromosomes are folded up (condensed), then split into two unreplicated chromosomes and separated into two new cells
Each chromosome in a G1 phase cells contains one ____, _____ ______ DNA molecule
long, double stranded
Each chromosome in an S phase cell contains ____ that is undergoing ____
DNA, replication
Each chromosome in a G2 phase cell is completely ____ and contains ___ double-stranded DNA molecules
replicated, two
Each chromosome in an M phase cell up to metaphase contains ____ double-stranded DNA molecules and contains ___ after anaphase begins
two, one
The ____ of genetic material in the nucleus is _____
location, organized
each chromosome occupies a ___ location in the nucleus – ____ ____
discrete, chromosome territories
heterochromatin
highly compacted chromosome structures
heterochromatin are located at the ____ of the nucleus
periphery
DNA is folded up into ____ more ____ chromosome structures
increasingly, compact
____ + histones ___, ____, ___, and ____ form nucleosomal DNA (beads on a string)
DNA, H2A, H2B, H3, H4
_____ DNA + histone ___ forms coiled nucleosome fibers
nucleosomal, H1
Coiled nucleosome fibers are looped into looped domains by _____
cohesins
Loops are folded up further by _____ during M phase
condensins
Interphase is
G1, S, and G2
Interphase chromosomes contain _____, _____ _____, and ____ _____
euchromatin, constitutive heterochromatin, facultative heterochromatin
Euchromatin is the _____ folded chromosome structure, containing genes that can be ____
least, expressed
Heterochromatin is a more ____ folded, _____ chromosome structure , containing genes that are not being _____
highly, compact, expressed
Constitutive heterochromatin is found in chromosome regions that are _____ packed in heterochromatin (____ and _____)
always, centromeres, telomeres
Facultative heterochromatin is found in chromosome regions that are packed in ____ in some cell types but in _____ in others
heterochromatin, euchromatin
The structure of chromatin at a particular location on a chromosome can be _____/______
modified/regulated
