Chapter 4 Biology

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transport vesicles

membranous spheres that bud from the rough ER

The fluid mosaic model of the plasma membrane is characterized by ________.

molecules moving freely past one another

The endosymbiont theory states that chloroplasts and mitochondria were previously

free-living prokaryotes

Ribosomes function

produce membrane proteins and secretory proteins

What is the smallest entity that exhibits all the characteristics of life?

Cells

Which cells contain membrane bound organelles?

Eukaryotic

Which carbon compound is composed of CH2O?

carbohydrate

How does DNA direct protein production?

1) DNA programs protein production in the cytoplasm by transferring its coded info to mRNA, which carries the order to the cytoplasm 2). it exits the nucleus through pores and attaches onto ribosome 3) ribosome moves along mRNA, and translates the genetic code to a protein

endomembrane system

A network of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles. (nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles)

Compare the structure and function of chloroplasts and mitochondria. Describe the adaptive advantages of extensive folds in the grana of chloroplasts and the inner membrane of mitochondria.

Chloroplasts are plant organelles that perform photosynthesis (light energy --> chemical energy of sugars). They contain stacked discs called grana and tubes to perform photosynthesis. More grana folds --> more surface area --> more output. Mitochondria are the organelles of cellular respiration and produce ATP from the energy of food molecules. There are numerous infoldings called cristae in the inner membrane. More cristae folds --> more surface area --> more output.

The term used to indicate the part of a eukaryotic cell where organelles are suspended in fluid is _________

Cytoplasm

Explain how the genetic information in the nucleus is used to direct the production of proteins in the cytoplasm.

DNA-containing genes in the nucleus programs protein production in the cytoplasm by transferring its coded information into messenger RNA. Messenger RNA then exits the nucleus through pores in the nuclear envelope. Ribosomes and the mRNA work together to translate genetic messages into different proteins. so pretty much: Nucleus ---> mRNA ----> ribosome

A major difference between prokaryotic and eukaryotic cells is that __________

Eukaryotic cells have organelles; prokaryotic cells do not

matrix

Innermost compartment of the mitochondrion, thick fluid

Compare the following pairs of terms, noting the most significant differences: light microscopes vs. electron microscopes, scanning electron microscopes vs. transmission electron microscopes, magnification vs. resolution, prokaryotic cells vs. eukaryotic cells, plant cells vs. animal cells.

Light microscopes solely use light that passes through the specimen and use lenses to enlarge the image while electron microscopes use beams of electrons to better resolve images. Scanning electron microscopes are used to examine cell surfaces and transmission electron microscopes are used to study the internal structure of cells. Magnification is an increase in the object's image size compared to its actual size while resolving power is the ability of an optical instrument to show two objects as separate. Plant cells distinctly contain a cell wall, chloroplasts, and a central vacuole while animal cells distinctly contain lysosomes and centrioles.

Which of the following are the two main components of cellular membrane?

Proteins and phospholipids

Compare the structures and functions of a plant cell wall and the extracellular matrix of an animal cell.

Rigid plant cell walls are made of cellulose to protect, maintain shape, and regulate water absorption of the cell. Animal cells lack cell walls and usually contain extracellular matrices to protect, support, and hold cells together in tissues. This helps animals to move around in contrast to plant cells (which is why animals can dance and plants can't)

Most antibiotics kill invading bacteria while minimally harming the host by _________?

Targeting structures found only in bacterial cells and not the host cells

Describe the functions of the cytoskeleton. Compare the structures and functions of cilia and flagella.

The cytoskeleton is a network of fibers/filaments throughout the cytoplasm. These fibers, such as microtubules give the cell anchorage shape. The cytoskeleton is EXTREMELY dynamic by moving around and is constantly reassembled.Cilia and flagella both have the same basic structure as appendages extending from the outside of cells, and they both help move cells (or move fluid over cells). However, cilia are short and numerous and move in a back-and-forth movement, while flagella are long, singly-occurring, and whip back and forth.

extracellular matrix

The substance in which animal tissue cells are embedded, consisting of protein and polysaccharides.

Describe the structure of the plasma membrane and other membranes of the cell. Explain why this structure is called a fluid mosaic.

The thin plasma and other membranes of cells are composed of mostly phospholipids (which form a double-layered bilayer) and proteins. It is fluid because molecules can move freely past one another and a mosaic because of the diversity of proteins in the membrane

explain how each word in the term fluid mosaic describes the structure of a membrane

a membrane is fluid, and it is diverse of embedded proteins

cytoskeleton

a network if fibers extending throughout cytoplasm, helps with support and movement. Nucleus is often held in place by a cytoskeletal cage of filaments. Cytoskeleton can quickly dismantle in one part of the cell by removing proteins submits and re-form in a new location

phospholipid bilayer

a two-layered membrane

microtubules

a type of fiber and are straight, hollow tubes composed of proteins

match the following organelles with their functions: a. ribosomes b. microtubules c. mitochondria d. chloroplasts e. lysosomes 1. movement 2. photosynthesis 3. protein synthesis 4. digestion 5. cellular respiration

a3, b1, c5, d2, e4

using a light microscope to examine a thin section of a large spherical cell, you find that the cell is 0.3 mm in diameter. The nucleus in micrometers?

about 0.075 mm

central vacuole (plant only)

accounts for more than half the volume of a mature plant cell, stores organic nutrients, and absorbs water (allowing cells to expand, and can contain poisons to protect against plant-eaters)

you look into a light microscope and view an unknown cell. What might you see that would tell you whether the cell is prokaryotic or eukaryotic?

b.

Which one of the following groups is composed of prokaryotic cells?

bacteria

eukaryotic cells

belong to the Eukarya domain

A plant cell has a versatile compartment that stores organic nutrients, absorbs water, and contains poisons that protect against plant-eating animals. This compartment is the _________.

central vacuole

prokaryotic cells

characterize organisms of domains Bacteria & Archaea

Within the nucleus of a cell, long DNA molecules and associated proteins form fibers called ____________.

chromatin

The function of the chloroplast is to ___________.

convert light energy to chemical energy

plant cell only: chloroplast

convert light energy to the chemical energy of food

cilia and flagella structure

core of microtubules wrapped in extension of plasma membrane

if you wanted to film the movement of chromosomes during cell division, the best choice for a microscope would be a

d

When a protein unfolds due to changes in pH, temperature, or salinity, the protein is said to

denature and lose function

Which of the following is stored in the lysosomes of the cell?

digestive enzymes

You're convinced that a sample you have is a carbohydrate. However, it tests negative with both iodine and Benedict's solution. What type of carb is it likely to be?

disaccharide

smooth ER

doesn't have ribosomes

chromosome

each long chromatin fiber has one chromosome

identify which one of the following structures includes all the others in the list: rough ER, smooth ER, endomembrane system, the Golgi apparatus.

endomebrane system

The nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles make up the _______________.

endomembrane system

what is the most significant structural difference between prokaryotic and eukaryotic cells?

eukaryotic cells have organelles

Describe the parts of the cell theory

everything is made from cells, and cells come from cells

Robert Hooke

first to observe "small chambers" in cork and call them cells.

chromatin

formed by long DNA molecules within the nucleus & associated proteins

importance of lysosomes

hereditary disorders (lysosomal storage diseases) are missing 1+ digestive enzymes in the lysosomes, and the lysosomes are unable to. break down certain proteins, and these diseases can be fatal in childhood

Nucleic acids can be broken down by _______ reactions to the monomers known as ______.

hydrolysis, nucleotides

cristae

inner membrane of mitochondria, numerous foldings

flagella

long projections that propel bacteria through a liquid environment, whiplike motion

Which organelles function in the endomembrane system?

lysosomes, Golgi apparatus, smooth & rough ER

ribosome transport (eukaryote)

made in nucleus, then transported through pores of nucleus into cytoplasm, where some ribosomes work, and others attach to ER

Endoplasmic Reticulum

main manufacturing facility within a cell, produces a lot of molecules. The ER is connected to the nuclear envelope, and it forms a labyrinth of tubes and sacs that run through the cytoplasm. Two parts of the ER: rough ER & smooth ER (connected but differ in structure)

Rough endoplasmic reticulum appears "rough" because _________________.

many ribosomes stud the outside of the ER membrane

organelles

membrane-enclosed structures that perform specific functions

Coded genetic information is produced in the nucleus and transferred to the cytoplasm in a molecule called _________.

messenger RNA

In addition to the nucleus, which of the following are organelles that contain DNA?

mitochondria and chloroplasts

Which organelles are involved in energy transformations?

mitochondria, chloroplast

cilia

more numerous than flagella and promote movement and they go back in forth

nucleus (EUKARYOTE only)

most important organelle, houses most of a eukaryotic cell's DNA, surrounded by double membrane

Golgi apparatus

named after its discoverer (Camillo Golgi). Function: refinery, warehouse, and shipping center. Works in close partnership w/ ER, it receives, refines, stories, and distributes chemical products of the cell. It receives stuff from the ER in transports vesicle (one side of Golgi is a receiving dock for vesicles and the other side is the shipping side for finished products (for other organelles or even outside the cell)).

DNA controls the cell by transmitting genetic messages that result in protein production. Place the following organelles in the order that represents the flow of genetic information from the DNA through the cell: nuclear pores, ribosomes, nucleus, rough ER, Golgi apparatus

nucleus, nuclear pores, ribosomes, rough ER, Golgi

chloroplast

organelles that perform photosynthesis, partitioned into 3 compartments by internal membranes: space between 2 membranes, stroma, grana

Mitochondria, the sites of cellular respiration, are found in _________.

plant cells and animal cells

Which of these distinguishes a plant cell from an animal cell?

presence of a cell wall

The sequence of amino acids refers to what level of protein structure?

primary

which type of cell is older?

prokaryotic

which type of cell is simpler?

prokaryotic

nucleolus

prominent structure within the nucleus, site where components of ribosomes are made

The Golgi apparatus mainly functions to modify __________.

proteins

Rough ER

refers to the appearance of the organelle, roughness is due to ribosomes on the outside of ER membrane. Functions: produce new membrane. Cells that need to secrete a lot of protein (like saliva glands) are rich in rough ER. Some products made by the rough ER are dispatched to other organelles use transport vesicles to do so

plasma membrane

regulates the traffic of molecules between cell & surroundings (ALL cells)

ribosomes (basic)

responsible for protein synthesis

What are the primary sites of protein production in a eukaryotic cell?

ribosomes

you can track the path of a protein within the cell from production through export by labeling them with radioactive isotopes. identify which of the following structures would be labeled in your experiment, in order: chloroplasts, Golgi, plasma membrane, smooth ER, rough ER, nucleus, mitochondria

rough ER, Golgi, plasma membrane

Compare the structures and functions of the following components of the endomembrane system: rough endoplasmic reticulum, smooth endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles.

rough ER: synthesize proteins smooth ER: synthesize lipids/ detoxify Golgi: shipping and handling Lysosomes: digestion Vacuoles: storage facility

lysosomes

sac of digestive enzymes found mostly only in animal cells, developed from vesicles that come off the Golgi. The enzymes within a lysosome can break down macromolecules. Some nutrients go to food vacuoles, and any small molecules that result, leave the lysosome and nourish the cell. Lysosomes also destroy harmful bacteria, and they also break down the large molecules of damaged organelles so the molecules are available to make a new organelle. They also help in embryonic development (digest webbing between fingers).

vacuoles

sacs that bud from the ER, Golgi, or plasma membrane. (come in lots of sizes and functions)

name two similarities in the structure/function of chloroplasts and mitochondria. Name two differences.

similar: energy, originated from prokaryotes differences: chloroplasts are only in plant cells, chloroplasts have 3 compartments

mitochondria

sites of cellular respiration, harvests energy from sugars and converts it to ATP, cells then use molecules of ATP as the direct energy source. Found in all. eukaryotic cells, envelop of 2 membrane encloses mitochondrion

the ER has to distinct regions that differ in structure and function. Lipids are synthesized within the ______, and proteins are synthesized within the _____

smooth ER, rough ER

capsule

some prokaryotes have this structure surrounding the cell wall for extra protection

1st compartment

space between 2 membranes that envelop the chloroplast

cell junctions

structures that connect to other cells (animal cells)

smooth ER functions

synthesis of lipids (sex hormones are enriched with smooth ER), detoxify stuff in the liver, can increase tolerance of drugs (kinda causes addiction)

cytoplasm

the entire region of the cell between the nucleus and plasma membrane

grana

the interior of a network of membrane-enclosed disks and tubes, solar power packs, trap light energy and convert it to chemical energy

phospholipids

the lipids surrounding the plasma membrane (only have 2 fatty acids, and a phosphate group, which is electrically charged, making it hydrophilic)

fluid mosaic

the molecules can float freely and are very diverse

What is the genetic center of the eukaryotic cell?

the nucleus

nuclear envelope

the nucleus is bordered by a. double membrane, similar in structure to plasma membrane

explain how antibiotics specifically target bacteria while minimally harming the human host.

they focus on killing the part of the bacterial cell that doesn't exist in an eukaryote cell.

stroma

thick fluid within the chloroplast

food vacuoles

tiny cytoplasmic sacs that many cells engulf nutrients into

ribosomes

tiny structures that build proteins according to instructions from DNA (ALL cells)

Which of the following correctly matches the organelle with its function?

vacuole ---> storage


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