ATDH BIOLOGY QUESTIONS AND
ANSWERS (GRADED A+)
Cell membrane - ANSWER-Hold cellular components and are mainly composed of
phospholipids, cholesterol, and proteins
Organelles - ANSWER-Cellular compartments enclosed by phospholipids bilateral
(membrane bound)
Are located within the cytosol (aqueous intracellular fluid) and help make up the
cytoplasm
Only eukaryotes contain membrane-bound organelles
Nucleoid - ANSWER-Where prokaryotes keep their genetic material
Nucleus - ANSWER-Primarily functions to protect and house DNA
DNA replication and translation occurs here
Nucleoplasm - ANSWER-Cytoplasm of the nucleus
Nuclear envelope - ANSWER-Membrane of the nucleus
Contains two phospholipid bilayers with a perinuclear space in the middle
Nuclear pores - ANSWER-Holes in the nuclear envelope that allow molecules to travel
in and out of the nucleus
Nuclear lamina - ANSWER-Provides structural support to the nucleus, as well as
regulating DNA and cell division
Nucleolus - ANSWER-Dense area that is responsible for making rRNA and producing
ribosomal subunits
Ribosomes - ANSWER-Work as small factories that carry out translation
Composed of ribosomal subunits
Rough er - ANSWER-Continuous with the outer membrane of the nuclear envelope and
is "rough" because it has ribosomes embedded in it
Lumen - ANSWER-Inside of the rough er
Smooth er - ANSWER-Not continuous with other membranes
Main function is to synthesize lipids, produce steroid hormones, and detoxify cells
, Golgi apparatus - ANSWER-Made up of cisternae (flattened sacs) that modify and
package substances
Lysosomes - ANSWER-Membrane-bound organelles that break down substances
(through hydrolysis) taken in through endocytosis
Transport vacuoles - ANSWER-transport materials between organelles
Food vacuoles - ANSWER-temporarily hold endocytosed food and later fuse with
lysosomes
Central vaacuoles - ANSWER-Very large in plants and have specialized membrane
called the tonoplast
Function in storage and material breakdown
Muscle contraction - ANSWER-actin microfilaments have directionality, allowing myosin
motor proteins to pull on them for muscle contraction
Intermediate filaments - ANSWER-Between microfilaments and microtubules in size
More stable than microfilaments and mainly help with structural support
Microtubules - ANSWER-Largest in size and give structural integrity to cells
Hollow and have walls made of tubulin protein dimers
Centrioles - ANSWER-Hollow cylinders made of nine triplets of microtubules
Storage vacuoles - ANSWER-store starches, pigments, and toxic substances
Contractile vacuoles - ANSWER-Found in single-called organisms and works to actively
pump out excess water
Endomembrane system - ANSWER-Group of organelles and membranes that work
together to modify, package, and transport proteins and lipids that are entering or
exiting a cell
Includes the nucleus, rough and smooth ERs, Golgi apparatus, lysosomes, vacuoles,
and cell membrane
Peroxisomes - ANSWER-Perform hydrolysis, break down stored fatty acids, and help
with detoxification
Mitochondria - ANSWER-Powerhouse of the cell
Produces ATP for energy use through cellular respiration
Chloroplasts - ANSWER-Found in plants and some protists
Carry out photosynthesis
ANSWERS (GRADED A+)
Cell membrane - ANSWER-Hold cellular components and are mainly composed of
phospholipids, cholesterol, and proteins
Organelles - ANSWER-Cellular compartments enclosed by phospholipids bilateral
(membrane bound)
Are located within the cytosol (aqueous intracellular fluid) and help make up the
cytoplasm
Only eukaryotes contain membrane-bound organelles
Nucleoid - ANSWER-Where prokaryotes keep their genetic material
Nucleus - ANSWER-Primarily functions to protect and house DNA
DNA replication and translation occurs here
Nucleoplasm - ANSWER-Cytoplasm of the nucleus
Nuclear envelope - ANSWER-Membrane of the nucleus
Contains two phospholipid bilayers with a perinuclear space in the middle
Nuclear pores - ANSWER-Holes in the nuclear envelope that allow molecules to travel
in and out of the nucleus
Nuclear lamina - ANSWER-Provides structural support to the nucleus, as well as
regulating DNA and cell division
Nucleolus - ANSWER-Dense area that is responsible for making rRNA and producing
ribosomal subunits
Ribosomes - ANSWER-Work as small factories that carry out translation
Composed of ribosomal subunits
Rough er - ANSWER-Continuous with the outer membrane of the nuclear envelope and
is "rough" because it has ribosomes embedded in it
Lumen - ANSWER-Inside of the rough er
Smooth er - ANSWER-Not continuous with other membranes
Main function is to synthesize lipids, produce steroid hormones, and detoxify cells
, Golgi apparatus - ANSWER-Made up of cisternae (flattened sacs) that modify and
package substances
Lysosomes - ANSWER-Membrane-bound organelles that break down substances
(through hydrolysis) taken in through endocytosis
Transport vacuoles - ANSWER-transport materials between organelles
Food vacuoles - ANSWER-temporarily hold endocytosed food and later fuse with
lysosomes
Central vaacuoles - ANSWER-Very large in plants and have specialized membrane
called the tonoplast
Function in storage and material breakdown
Muscle contraction - ANSWER-actin microfilaments have directionality, allowing myosin
motor proteins to pull on them for muscle contraction
Intermediate filaments - ANSWER-Between microfilaments and microtubules in size
More stable than microfilaments and mainly help with structural support
Microtubules - ANSWER-Largest in size and give structural integrity to cells
Hollow and have walls made of tubulin protein dimers
Centrioles - ANSWER-Hollow cylinders made of nine triplets of microtubules
Storage vacuoles - ANSWER-store starches, pigments, and toxic substances
Contractile vacuoles - ANSWER-Found in single-called organisms and works to actively
pump out excess water
Endomembrane system - ANSWER-Group of organelles and membranes that work
together to modify, package, and transport proteins and lipids that are entering or
exiting a cell
Includes the nucleus, rough and smooth ERs, Golgi apparatus, lysosomes, vacuoles,
and cell membrane
Peroxisomes - ANSWER-Perform hydrolysis, break down stored fatty acids, and help
with detoxification
Mitochondria - ANSWER-Powerhouse of the cell
Produces ATP for energy use through cellular respiration
Chloroplasts - ANSWER-Found in plants and some protists
Carry out photosynthesis
