AP Bio Chapter 6: Cell Organelles

Robert Hooke

built a microscope in 1663 and looked at dead bark from oak trees

pond water

Anton van Leeuwenhoek built a microscope to observe this and other living things

life

cells are the basic unit of

cell theory

all living things are composed of cells

obtaining energy, removing waste, reproducing

cells are the basic unit of living things and carry on similar functions, including

other cells

all cells are produced from

microscopes

the cell theory would not have been possible without

compound light microscope

magnifies images using two lenses (for objects as small as a millionth of a meter)

electron microscope

uses a beam of electrons focused by magnetic fields (used for objects as small as 1 billionth of a meter)

magnification

makes things look larger

resolution

makes objects clearer and detailed

contrast

the darkness or lightness of areas of an image

eyepiece (ocular lens) and objectives

compound light microscopes magnify light using two lenses:

1000x

light microscopes can only magnify objects to about _____ due to diffraction and scattering

transparent

cells are nearly __________, which is why scientists use stains, dyes and fluorescence to view cell components

electron microscopes

magnifies objects using a beam of electrons instead of light and have higher magnification and resolution

surface

scanning electron microscopes:

internal

transmission electron microscopes:

cell fractionation

takes cells apart and separates the major organelles from one another

centrifuges

fractionate cells into their component parts (differential centrifugation)

biochemistry and cytology

fields of study that correlate cell function with structure

prokaryotic cell

DNA is not enclosed within a membrane

eukaryotic cell

most of the cell’s DNA is located within the nucleus

bacteria and archaea

prokaryotic cell organisms:

protists, fungi, animals, plants

eukaryotic cell organisms:

plasma membrane, cytosol, chromosomes, ribosomes

organelles that all cells share:

plasma membrane

barrier that encloses the cell and regulates the passage of molecules in and out the cell

cytosol/cytoplasm

a jelly-like semifluid that holds the components of the cell

chromosomes

threadlike structure composed of protein and genes

ribosomes

particles composed of RNA and associated proteins found in the cytoplasm that create proteins

smaller

prokaryotes are (smaller/bigger) than eukaryotes

nucleoid

prokaryotes do not have a nucleus, but DNA in an unbound region called the:

plasma membrane

in prokaryotes, the cytoplasm is bound only by the:

double membrane

eukaryotes have DNA in a nucleus bounded by a:

membrane-bound

the organelles of eukaryotic cells are

nucleus

contains most of the DNA (genes) in a eukaryotic cell

ribosomes

use the information from the DNA to make proteins

nuclear envelope

double membrane consisting of a lipid bilayer that encloses the nucleus

pores/pore complex

regulate the entry and exit of molecules from the nucleus, and contain a structure called

nuclear lamina

within the nuclear envelope is lining called:, which is composed of proteins and maintains the shape of the nucleus

chromatin

a chromosome contains one DNA molecule associated with proteins, called:

ribosomal RNA (rRNA) synthesis

the nucleolus is the site of:

cytosol

free ribosomes build proteins in the:

on the outside of the endoplasmic reticulum/the nuclear envelope

bound ribosomes build proteins:

endomembrane system

various membrane-bound organelles in eukaryotes that modify, package, and transport proteins and lipids

smooth endoplasmic reticulum

synthesizes lipids, metabolizes carbs, detoxifies drugs and poisons, and stores calcium ions

testes/ovaries

cells that synthesize and secrete the hormones listed are rich in smooth ER

liver cells

enzymes that help detoxify drugs and poisons are found in

rough endoplasmic reticulum

many cells secrete proteins produced by ribosomes attached to the:

insulin

pancreatic cells synthesize __________ later secreted into the bloodstream

ER lumen

a new polypeptide folds into its 3D shape as it enters the

glycoproteins

secretory proteins are mostly ______________, proteins with carbohydrates

ER lumen

the carbohydrates are attached to the proteins in the

vesicles

after secretory proteins are formed, the proteins depart from the ER in:

Golgi apparatus

consists of flattened membranous sacs called cisternae

transport to the Golgi apparatus

proteins that are made in the ER:

modifies products of the ER, manufactures certain macromolecules, sorts and packages materials into transport vesicles

functions of the Golgi apparatus:

cis face

“receiving” side of Golgi apparatus

trans face

“shipping” side of Golgi apparatus

lysosomes

membranous sacs of hydrolytic enzymes that can digest macromolecules

acidic

lysosomes work best in an ___________ environment

rough ER

hydrolytic enzymes and lysosomal membranes are made by ________ and then transferred to the Golgi apparatus for further processing

trans face

some lysosomes arise by budding from this face of the Golgi apparatus

phagocytosis

when a cell engulfs another cell, forming a food vacuole

autophagy

the process of lysosomes using enzymes to recycle the cell’s own organelles and macromolecules

vacuoles

large vesicles derived from the endoplasmic reticulum and Golgi apparatus

selective

vacuolar membranes are ____________ in transporting solutes. therefore, the inside of the vacuole differs from the cytosol

food vacuoles

are formed by phagocytosis

contractile vacuoles

found in many freshwater protists and pump excess water out of cells

hydrolytic enzymes

in plants and fungi, vacuoles have:

important organic compounds

in plants, small vacuoles can hold reserves of:

poisonous/unpalatable

some protect the plants against herbivores by storing compounds that are:

pollinating insects to flowers

some plant vacuoles contain pigments, such as the red and blue pigments of petals that attract:

central vacuole

the plant cell’s main repository of inorganic ions such as potassium and chloride

growth

the central vacuole plays a major role in the _________ of plant cells

mitochondria

the site of cellular respiration, the metabolic process that uses oxygen to generate ATP

cristae

mitochondria have a smooth outer membrane and an inner membrane folded into:

intermembrane space and mitochondrial matrix

the inner membrane creates two compartments:

mitochondrial DNA and ribosomes

the matrix contains many different enzymes as well as the:

catalyzed

some metabolic steps of cellular respiration are ______________ in the mitochondrial matrix

large surface area

the highly folded surfaces of the cristae give the inner mitochondrial membrane a:

chloroplasts

found in plants and algae, and are the sites of photosynthesis

chlorophyll

chloroplasts contain the green pigment ________________, as well as enzymes and other molecules that function in photosynthesis

thylakoids

membranous sacs in chloroplasts, stacked to form a granum

stroma

internal fluid in chloroplasts

plastids

the group of plant organelles that chloroplasts belong in

endosymbiotic theory

mitochondria and chloroplasts have similarities with bacteria

endosymbiont

an early ancestor of eukaryotes engulfed an oxygen-using non-photosynthetic prokaryotic cell. the engulfed cell formed a relationship with the host cell, becoming an _______________

mitochondria

endosymbionts evolved into:

chloroplast

at least one of these cells may have then taken up a photosynthetic prokaryote, which evolved into a:

both enveloped by a double membrane, contain free ribosomes and circular DNA molecules, and grow and reproduce somewhat independently in cells

the three similarities between mitochondria and chloroplasts that support this theory:

oxidative

peroxisomes are ___________ organelles, unknown to how they are related to other organelles

peroxisomes

specialized metabolic compartments bounded by a single membrane

remove hydrogen atoms and transfer them to oxygen

peroxisomes contain enzymes that:

hydrogen peroxide (H2O2), which is toxic but later converted to water

peroxisomes form:

break fatty acids into smaller molecules for respiration

some peroxisomes use oxygen to

detoxify alcohol and other harmful compounds

in the liver, peroxisomes:

glyoxysomes

found in the fat-storing tissues of plant seeds and are used to convert fatty acids to sugar to feed the emerging seedling

endosymbiotic evolution

many peroxisomes increase in number by splitting after reaching a certain size which can indicate:

cytoskeleton

a network of fibers that helps to support the cell and maintain its shape