Learnsmart Zoology (Chapter 3)

how do water and ions cross the plasma membrane

through channels

The ____________ ____________ is a stack of membranes and cisternae that function in the packaging and processing of proteins synthesized by rough ER

golgi complex

internal membranes

surround organelles, are the site of enzymatic reactions, compartmentalize the cell

__________, macromolecules, __________, tissues, organs, ____________

atoms, cells, organism

___________, prophase, metaphase, __________, ____________

interphase, anaphase, telophase

To maintain a constant number of chromosomes in the next generation, animals that exhibit _________ reproduction must produce gametes with half the chromosome number of somatic cells in a process called meiosis

sexual

Kinetochore microtubules shorten, centrosomes move farther apart, sister chromatids separate during

anaphase

phases of the cell cycle: G1, ___, ____, mitosis, cytokinesis

S, G2

The ___________ is a system of filaments and tubules providing support for the cell and a means for locomotion and intracellular movement of components

cytoskeleton

what is contained within the nuclei

chromosomes, nucleoplasm, nucleoli

during cytokinesis, a ____________ furrow appears and constricts the dividing cell at the midline

cleavage

daughter chromosomes form clusters at opposite poles, spindles fibers disappear, and chromosomes decondense during

telophase of mitosis

daughter chromosomes reach opposite poles at the beginning of

telophase

___________ are double-membrane bound organelles that are frequently called "power generators" of the cell because they convert energy to a usable form for cell usage

mitochondria

osmosis is the movement of ________ across a membrane

water

the plasma membrane is composed of two layers of ___________ molecules with their hydrophobic portions toward the inside and their hydrophilic ends toward the outside

phospholipid

Eukaryotic cells are enclosed by the _________, which is thin and selectively permeable

plasma membrane

The double membrane surrounding the nucleus in eukaryotic cells is called the

nuclear envelope

what are present in prokaryotes and eukaryotes

DNA, proteins, ATP

in ___________ diffusion, a transporter protein assists a molecule to diffuse across the plasma membrane

facilitated

the interval between one cell division and the next cell division is called

the cell cycle

Endocytosis is the transport of materials into cells usin

vesicles

In prophase, microtubules are synthesized between the centrosomes to form an oval-shaped ________ that plays a role in separating chromosomes during mitosis

spindle

The extrusion of substances from a cell by the fusion of a vesicle with the plasma membrane is called

exocytosis

During prophase, the centrioles, spindle, asters, and microtubules are collectively known as the ______________ spindle

miotic

The _______________ endoplasmic reticulum is the site of lipid synthesis, whereas the ___________ endoplasmic reticulum includes bound ribosomes that synthesize proteins

smooth, rough

chromatids align in the center of the cell along the spindle equator

metaphase

the constricted area of a chromosome is called the _____________ and is the location of the kinetochore proteins

centromere

movement of macromolecules within a cell, cell support maintenance of cell form are functions of the

cytoskeleton

transport substances across the membrane, act as self-recognition molecules, form pores for small molecules are functions of proteins within the

plasma membrane

move chromosomes during cell division, tubulin subunits are dimes, form cilia and flagella

microtubules

the __________ is a microtubbule organizing center located near the nucleus

centrosome

the hold cells together, they resist cell stretching

intermediate filaments

play a role in cell signaling, can move cells or fluid around cells

cilia

desmosomes function in

strengthening tissues

microfilaments are composed of the protein

actin

microtubules are composed of a protein called

tubulin

cell junctions called ________ consists of ellipsoid discs within the plasma membrane that appear increase tissue strength and serve as 'spot welds'

desmosomes

about 40% of the energy produced by cells is consumed by

sodium-potassium pumps

components of the endomembrane system

vesicles, lysosomes, golgi complex, ER

during mitosis, the microtubules of the spindle bind to chromosomes at a disk of proteins called the

kinetochore

chromatin is composed of

DNA binding proteins, DNA

molecules that are present in animal cell membranes

phospholipids, glycoproteins, cholestrol

structures within the nucleus that consist of loosely condensed chromatin

chromosomes

Every somatic cell in humans has __ chromosomes

46

which stage of the cell cycle is DNA replicated

S

phagocytosis is a type of endocytosis in which large solid particles are

ingested

a ________ _______ or kinetosome is a structure at the base of a cilium or flagellum and is identical in structure to a centriole

basal body

in adhesion junctions, transmembrane proteins are connected to ___________ ____________ and thus indirectly link the cytoskeletons of adjacent cells

actin microfilaments