Bio 143 Exam 4

The majority of human coronavirus infections (all coronaviruses, not just SARS Cov2) cause what type of condition?

asymptomatic

the majority of COVID-19 cases are caused by

people without symptoms

What does the human microbiome refer to?

bacteria that live on and in our body, and improve our health

Vaccines function by

stimulating the immune system response so when you are actually exposed to the virus, you can protect yourself by eliminating the virusCo

Could the creation of antibodies from a vaccine be harmful? Example?

Yes; yellow fever

What are viruses caused by?

spread from isolated populations, rapid mutation of the RNA genome, spread from other animals

What kind of virus is coronavirus?

positive sense

Where is the DNA of a prokaryote located?

cytoplasm

What cell type has the greatest diversity (different types)?

prokaryotes

Characteristics of prokaryotes

oldest cell type, small and simple, lack nucleus, lack organelles, single-celled

Characteristics of eukaryotes

evolved from prokaryotes, larger and more complex, contain nucleus, contain organelles, single-celled or multicellular

Characteristics that prokaryotes and eukaryotes share

have DNA, have ribosomes, have cytoplasm, have plasma membrane

What do antibiotics kill?

bacteria

What type of cell reproduces most rapidly?

prokaryotes

How do viruses make more of themselves?

use host cell machinery

What characteristics are shared by all cells?

surrounded by a membrane, genetic material, regulation, reproduction, respond to stimuli

What is the name for the types of bacteria and archaea that thrive under extreme conditions?

extremophiles

What is not a possible form of genetic material for a virus?

protein

The entire infectious virus particle

virion

What is a virion made of?

nucleic acid and outer shell of protein

How many bacterial cells exist on the planet?

10^30

How does antiviral medicine act?

disrupts virus functions (infecting host cells, replication, and release from host cells)

Why is a plasmid not a prokaryotic organelle?

prokaryotes do not have organelles

What are plasmids?

loops of DNA found in some bacteria, contain "special" genes not essential to life function, can be transferred from one bacterial cell to another

What is the simplest virus made out of?

DNA, capsid protein coat

Where are proteoglycans abundant?

the extracellular matrix

What are proteoglycans made of?

a polysaccharide with protein/carbohydrate branched attachments

The protein that links collagen and integrin

fibronectin

What are centrioles made up of?

microtubules

When are motor proteins capable of movement?

when ATP is hydrolyzed, releasing energy

Dynein and myosin are

motor proteins

Function of cell wall in plants

protects the plant cell, prevents excessive uptake of water, maintain shape

Only in plant cells; provides communication between cytoplasm of two adjacent cells; pore through the cell wall

plasmodesmata

In animal cells; pores that provide a link between cytoplasm of adjacent cells; can be used to send signals rapidly between cells

gap junctions

In animal cells; proteins that stitch the plasma membranes of two adjacent cells together to prevent material from moving between adjacent cells; particularly important in the epithelium lining the digestive tract and the respiratory tract

tight junctions

protein filament structures that are used to keep cells together; prevents cells from being pulled apart

desmosomes

How are cilia and flagella capable of movement?

motor proteins interacting with microtubules

How does fluorescence microscopy work?

uses an antibody molecule as a probe, is a form of light microscopy

What is the plant cell wall made of?

cellulose

smallest; made up of a single globular protein that polymerizes and intertwines to make a double-stranded structure

actin (microfilaments)

largest; made up of alpha and beta subunits which form polymers and join together 13 polymers or columns to form a hollow tube

microtubules

in between in size; most diverse; strongest

intermediate filaments

uses sunlight energy and makes sugars

chrloroplast

storage vesicle of plants

vacuole

site of ribosomal RNA synthesis

nucleolus

protein folding, some modification

rough endoplasmic reticulum

contains hydrolytic enzymes, low pH, is used to digest material from endocytosis or damaged organelles

lysosome

protein synthesis (also known as translation)

ribosomes

contains the DNA

nucleus

oxidation reduction reactions with hydrogen peroxide produced

peroxisome

protein modification & protein sorting

Golgi apparatuss

structure from which spindle fibers are made, used in mitosis

centrosome with pair of centrioles

cellular support and structure

cytoskeleton

ATP synthesis

mitochondria

lipid synthesis

smooth endoplasmic reticulum

What motor protein does actin interact with?

myosin

What organelles are involved in the endomembrane system?

plasma membrane, rough ER, Golgi, lysosomes

What is the endomembrane system?

group of organelles and membranes in eukaryotic cells that work together modifying, packaging, and transporting lipids and proteins

interacts with dyne to move vesicles; used to move cilia and flagella; forms spindle fibers which move chromosomes apart during mitosis

microtubules

interacts with the motor protein myosin during muscle contraction and movement of cells or cytoplasm

actin

makes up the nuclear lamina; used for string external structures like hair and horns

intermediate filaments

What cells have a cell wall?

bacterial cells, plant cells

You are a scientist interested in measuring the average number of vesicles on the cis side of the Golgi apparatus. You have decided that you will count the vesicles in 100 microscopic images of cells. Which type of analysis would be best suited to this type of study?

transmission electron microscopy

What is the material that surrounds animal cells?

extracellular matrix

What is the extracellular matrix made of?

collagen

Where can ribosomes be found?

in the rough endoplasmic reticulum and cytosol of eukaryotic cells

Where does photosynthesis occur?

chloroplasts

What produces ATP in animal cells?

mitochondria

What is endosymbiosis?

one cell engulfing another and both cells benefit from the relationship

What houses most of a eukaryotic cell's DNA?

nucleus

Where is the nucleolus located?

the nucleus

Where can you find H2O2 (hydrogen peroxide) in a cell?

peroxisomes

You're working with a cell line in the laboratory and discover a mutation in a gene that makes your cells unable to metabolize carbohydrates anymore. What organelle do you think this gene is involved in regulating?

smooth endoplasmic reticulum

Which cell types have cell walls?

plants, fungi, prokaryotes

What is a shared characteristic between mitochondria and chloroplasts?

self-replication

Which organelle houses thylakoids?

chloroplasts

Plasma cells are an immune cell found in mammals that produce large quantities of antibodies, which are proteins. Which organelle would you expect to be enlarged in these cells?

rough endoplasmic reticulum

What transports vesicles throughout the cell?

Golgi apparatus

What is the cellular mechanism deals with defecting or damaged organelles?

autophagy

What allows for the translocation of mRNA from the nucleus into the cytoplasm or endoplasmic reticulum?

nuclear pores

What is phagocytosis?

ingestion of large molecules via phagocytes

What is the terminal fate of a phagosome?

lysosomal fusion and degradation

What kinds of microscopy are there?

light, fluorescent, transmission electron, scanning electron

How are cells studied?

microscopy, cell fractionation, biochemical analyses

lenses refract light to magnify the image

light microscopy

What does the microscopic image quality depend on?

magnification, resolution, contrast

If you were to examine the shape of bacteria, what kind of microscope would you use?

light or scanning electron

If you were trying to examine the contents of an organelle, what kind of microscope would you use?

transmission electron

What does cell fractionation do?

homogenizes the cells into a homogenate, then centrifuges the vial to separate the different parts of the cell

What are some types of biochemical analyses?

DNA, RNA, proteins, lipids, carbohydrates

all living organisms are composed of cells, the cell is the basic unit of life, cells come from pre-existing cells

original cell theory

energy flow occurs within cells, heredity information (DNA) is passed from cell to cell, all cells have the same basic chemical composition

modern cell theory

Does the ratio of surface area to volume of cells increase or decrease as a cell gets bigger?

decreases

What two organelles are believed to have evolved via endosymbiosis?

mitochondria and chloroplast

increases the surface area of the plasma membrane

microvilli

used to move cells or material

cilia or flagella

dynamic network of protein fibers in a cell

cytoskeleton

What are the functions of the cytoskeleton?

mechanical support, motility, regulation

microtubules

functions of microtubules

maintenance of cell shape, cell motility, chromosome movements in cell division, organelle movements