Chapter 21 test Flashcards
what is a particle made of proteins, nucleic acids, and sometimes lipids that can replicate only by infecting living cells
Virus
what is a protein coat surrounding a virus
Capsid
what is a type of infection in which a virus enters a cell, makes copies of itself, and causes the cell to burst
lytic infection
what is a kind of virus that infects bacteria
bacteriophage
what is a type of infecting in which a virus embeds its DNA into the DNA of the host cell and is replicated along with the host cell’s DNA
lysogenic infection
what is the bacteriophage DNA that is embedded in the bacterial hist’s DNA
prophage
RNA virus that contains RNA as its genetic information
retrovirus
is a virus living or nonliving
nonliving
how can viruses reproduce
by infecting other living cells
Viruses contain genetic information in the form of ______ or _______
RNA/DNA
What are two viruses’ patterns of infection
lytic and lysogenic infection
What happens when you get a common cold
cold viruses attack with a very simple, fast-acting infection
viruses cause disease by directly ______ ______ or by affecting cellular processes in ways that upset _______
living cells/homeostasis
What are two types of prevention and treatment of viruses
antiviral medication and others that help prolong the lives of people infected with HIV
Are viruses parasites
yes
what is the unicellular organism that lacks a nucleus
prokaryote
What is a type of asexual reproduction in which an organism replicates its DNA and divides in half, producing two identical daughter cells
Binary fission
what is a structure produced by prokaryotes in unfavorable conditions; a thick internal wall that encloses the DNA and a portion of the cytoplasm
endosphere
what is the process in which paramecia and some prokaryotes exchange genetic information
conjugation
What is a disease-causing agent
pathogen
what is the preparation of weakened or killed pathogens used to produce immunity to a disease
Vaccine
What is a group of drugs used to block the growth and reproduction of bacterial pathogens
antibiotic
Where is the DNA of prokaryotes located
cytoplasm
Prokaryotes belong to what two domains
Bacteria and Archaea
The cell walls of bacteria contain ___________, which is a polymer of sugars and amino acids that surrounded the cell membrane
peptidolycan
Many archaea live where
extremely harsh environments
what are the three basic shapes of prokaryotes
rod, spherical, and spiral
Most prokaryotes reproduce by what process
Binary fission
Since many prokaryotes reproduce asexualy, what two ways do their populations evolve
mutations and through conjugation
In a typical human intestine there may be as many as how many bacteria
30 trillion bacteria
Bacteria produce disease in what two general ways
by destroying living cells or release chemicals that release homeostasis
What are infections that evolve and make medicines less effective
superbugs
What is an unknown disease that becomes hard to control
An emerging disease
what is a short hairlike projection that produces movement
cilium
What is a structure used by protists for movement; produces movement in a wavelike motion
flagellum
what is a life cycle that has two alternating phases—a haploid phase and diploid phase
alternation of generations
What are eukaryotes that are not members of the plant, animal, or fungi kingdom
protists
How many species of protists are there
300,000
How many major clades or groups of protists are there
6
What are the ways protists move
change their cell shape, means of specialized organelle, don’t move except by wind or water
What ways do protists reproduce
mitosis, or asexual reproduction
What are complex carbohydrate that makes up the cell walls of fungi; also found in the external skeletons of arthropods
Chitin
what is one of many long, slender filaments that makes up the body of a fungus
hypha
what is a reproductive structure of a fungus that grows from the mycelium
fruiting body
what is a densely branched network of the hyphae of a fungus
mycelium
what is the symbiotic association between a fungus and a photosynthetic organism
lichen
what is a symbiotic association of plant roots and fungi
mycorrhiza
what is heterotrophic with cell walls
fungi
how can fungi reproduce asexually
spores by air or water
do most fungi reproduce sexually or asexually
sexually
How many species of fungi are known
100,000
What are the four major phyla of fungi
Ascomycota, zygomycota, trititiomicota
how do fungi help ecosystems maintain homeostasis
breaking down dead organisms, or recycling elements
How can parasitic fungi cause serious diseases in plants and animals
disrupting homeostasis
What kind of relationships do fungi form with plant roots
mutualistic
Scientists estimate that what percent of plant species form mycorrhizae with fungi
80-90 percent
