Chapter 4: Cell Structure and Funtion

The Cell Theory

1. All living things are made of cells 2. Cells are the basic unit of structure and function in all organisms 3. All cells come from other cells through the process of mitosis(cell division)

cytoplasmic streaming

A circular flow of cytoplasm, involving myosin and actin filaments, that speeds the distribution of materials within cells.

Endoplasmic Reticulum

A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids BOTH

Transport Vesicle

A tiny membranous sac in a cell's cytoplasm carrying molecules produced by the cell.

gap junction

ANIMAL allow communication and exchange between adjacent cells ( called plasomodesmata in plant cells)

tight junctions

ANIMAL provide tight leakproof seals between cells ex. epithelial cells that line blood vessels

cytoplasm

An organelle which is liquid material inside the cell, it contains many nutrients, many reactions (metabolic) occur here, BOTH

SER

ER That synthesizes lipids, phospholipids, steroids, and enzymes BOTH

Schleiden

This man was a botanist, "all plants are made of cells"

Chromatin

a cell part that is "Threadlike" material made of DNA (not dividing form of DNA) BOTH

nuclear envelope

a cell part that surrounds the nucleus, contains nuclear pores that allows materials (ribosomes and RNA) in and out BOTH

prokaryotic

a cell that does not have a nucleus or membrane bound organelles. Characteristics: round, rod or spiral shaped, relatively small, heterotrophic/autotrophic, plasma membrane, cell wall, cytoplasm, ribosomes, flagellum, cytoskeleton

Pseudopod

a false foot, formed by breaking down of cytoskeleton, do not always exsist

Demsosomes

adhesion junctions or adherents ANIMAL fasten cells together with cytoskeletal fibers, allow stretching. Ex. muscle and skin

centrioles

aid in cell division, made of protein microtubules ANIMAL ONLY

protists

although they are single celled, the are eukaryotic and require all organelles to stay alive. Ex. Amoeba

Nucleus

an organelle that controls all cell activities and function (metabolic function) contains the genetic material. BOTH

cell membrane

an organelle that is non-polar, hydrophobic, semi permeable barrier made of phospholipid and protein, it controls what goes in and out of the cell, it maintains the internal environment from external environment, maintains homeostasis.PHOSPHOLIPID BILAYER BOTH

Nucleolus

an organelle that makes ribosomes, it is a dense spot located in the nucleus. BOTH

ribosomes

an organelle that synthesizes proteins, including enzymes, these tiny structures can be attached to the ER or free floating in the cytoplasm. BOTH

mitochondria

an organelle that uses oxygen to release energy from food, cellular respiration occurs, ATP is the type of energy

Plant Cells

box rectangular/ autotrophic/ preforms photosynthesis/ large/ membrane bound organelles/ cell membrane and wall cytoplasm ribosomes nucleus RER SER Golgi apparatus, mitochondria, chloroplasts, central vacuole, cytoskeleton

levels of organization

cells tissues organ organ systems complex organism

stem cells

cells that are undifferentiated or unspecialized

epithelial cells

cells that cover or line surfaces or organs, examples: lining on inside of cheek

eukaryotes

cells that does have a nucleus and membrane bound organelles: animal plant fungi and protist kingdoms

Plasomodesmata

channels between adjacent plant cells that allow chemical messages and nourishment to be shared

amoeba

chaos- no set shape or structure

Chromosomes

coiled rod-like DNA and are present during cell division BOTH

Secretory Vesicle

contain secretions that will be discharged from the cell these vesicles will perform exocytosis (fusing with the plasma membrane to empty contents)

Chromoplast

contains color pigments for petals and flowers, Organelles that contain pigments used in photosynthesis

microfilaments

fine thread like strands of protein called ACTIN that aid in cytoplasmic streaming, connect microtubules.

Leeumwenhoek

first man to view living cells, discovered bacteria, credited with making of first microscope

Animal Cells

irregular/round shape/ heterotrophic/relatively large/membrane bound organelles/ cell membrane/ cytoplasm/ribosomes/ nucleus/ RER/SER/ Golgi Apparatus/lysosomes/mitochondria/cytoskeleton/flagellum/ centriole

flagellum

long whip like structure made of microtubules that allows movement, it is located outside the cell membrane, SOME ANIMAL, SOME PROKARYOTES

cell wall

made of cellulose, gives cell its boxy structure, found in plants, PREVENT THE PLANT FROM ABSORBING TOO MUCH WATER

Microtubules

main support beams, long hallow tubes made of the protein TUBULINs, the help maintain cell shape, they provide tracks for cell organelles and vesicles to move on. found in centrioles, cilia, and flagella.

RER

modifies and secretes proteins, produces more membranes for other organelles. BOTH

Golgi Apparatus

packages and prepares proteins to be sent out of the cell (secreted) Flattened membrane sacs, lysosomes are formed here, a protein is given its final shape here BOTH

contractile vacuole

predominant in protists and algae acts like a pump to suck in fluids and food from outside environment

Osmoregulation

prevents it from bursting or being crushed, water regulation, also aids in regulation

Cytoskeleton

proteins in the cytoplasm that form a web which helps to maintain cell shape/structure. Holds the organelles in place

life processes

respiration nutrition excretion synthesis transport reproduction regulation growth all are required to maintain homeostasis

Intermediate Filament

rope like proteins that reinforce cell shape and anchor organelles

organelles

structures with a specialized function within a cell

food vacuole

substances of nutrition enter through the membrane and are encapsulated. Phagocytosis; cell eating Pinocytosis:cell drinking

cell

the basic unit of structure and function in all living things, smallest unit of life, must be able to carry out all the life processes

Cell junctions

these allow communication and exchange between adjacent cells

lysosomes

these consist of hydrolytic enzymes. 1. Digestion or food particles by joinging together with food vacuoles 2. white blood cells kill bacteria, 3. recycle materials by digesting malfunctioning organelles. small vesicles that contain digestive enzymes, helps digest food, bacteria and old cell parts, and can release their contents to preforms cell suicide ANIMAL ONLY

Virchow

this made said "life comes from life" all cells come from preexisting cells by cell division

Hooke

this man viewed cork cells, created the term cells.

Schwann

this man was a zoologist, "all animals are made of cells"

leucoplast

this store starch (Amylose) PLANT

Endosymbiotic Theory

this theory explains how prokaryotes evolved into eukaryotes. 1. Small aerobic prokaryotic cells were engulfed by larger prokaryotic cells in a process called endocytosis(inside the cell) 2. Rather than digesting the cell, the two cells formed a symbiotic (beneficial) relationship. The host cells helps provide nutrients and the internal cells help to produce energy. 3. Eventually, the two cells became interdependent to survive.

Cilia

tiny hairlike projections composed of microtubules, propel organism through fluid medium

bacteria

type of organism in the monera kingdom that is prokaryotic

Vacuole

vessicles that store water food and waste, in animal, they are small round and numerous, in plants they have a large central _______. This makes the plant firm. BOTH

chloroplast

where photosynthesis occurs, contains the pigment chlorophyl, sunlight gets converted into sugar. PLANTS