Cells and Tissues - Chapter 3

Carry out all chemical activities needed to sustain life

Cells and Tissues

are the building blocks of living things

Cells

are group of cells that are similar in structure and function

Tissues

Cells are not the

same

All ___ share general structure

cells

What are the three main regions of cells?

Nucleus, Cytoplasm, Plasma membrane

Control center of the cell

Nucleus

Contains genetic material (DNA)

Nucleus

Three regions of Nucleus

Nuclear membrane, Nucleolus, Chromatin

Barrier of nucleus

Nuclear Membrane

Consists of a double phospholipid membrane

Nuclear Membrane

Contain nuclear pores that allow for exchange of material with the rest of the cell

Nuclear Membrane

Nucleus contain one or more ___

Nucleoli

Sites of ribosome production

Nucleoli

Ribosomes then migrate to the cytoplasm through ___

nuclear pores

Composed of DNA and protein

Chromatin

Scattered throughout the nucleus

Chromatin

condenses to form chromosomes when the cell divides

Chromatin

Barrier for cell contents

Plasma Membrane

Double phospolipid layer

Plasma Membrane

what are the double phospholipid layer of the plasma membrane?

Hydrophilic heads and Hydrophobic tails

other materials in plasma membrane

Protein, Cholesterol, Glycoproteins

Finger-like projections that increase surface area for absorption

Microvili

Membrane junctions that are impermeable

Tight junctions

Membrane junctions that are anchoring junctions

Desmosomes

Membrane junctions that allow communication (commonly found in the heart and between embryonic cells)

Gap junctions

Material outside the nucleus and inside the plasma membrane

Cytoplasm

Fluid that suspends other elements

Cytosol

Metabolic machinery of the cell

Organelles

Non-functioning units

Inclusions

Made of protein and RNA & Sites of protein synthesis

Ribosomes

Found at two locations: Free in the cytoplasm & Attached to rough endoplasmic reticulum

Ribosomes

Fluid-filled tubules for carrying substances

Endoplasmic reticulum (ER)

Studded with ribosomes & Site where building materials of cellular membrane are formed

Rough Endoplasmic Reticulum

Functions in cholesterol synthesis and breakdown, fat metabolism, and detoxification of drugs

Smooth Endoplasmic Reticulum

Modifies and packages proteins and produces: Secretory vesicle, Cell membrane components & Lysosomes

Golgi apparatus

Contain enzymes that digest nonusable materials within the cell

Lysosomes

-Membranous sacs of oxidase enzymes

-Detoxify harmful substances

-Break down free radicals (highly reactive chemicals)

-Replicate by pinching in half

Peroxisomes

-“Powerhouses” of the cell

-Change shape continuously

-Carry out reactions where oxygen is used to break down food

-Provides ATP for cellular energy

Mitochondria

Network of protein structures that extend throughout the cytoplasm

Cytoskeleton

Provides the cell with an internal framework

Cytoskeleton

Type of Cytoskeleton where it is most involved in motility and cell shape changes. actin is one of it and it forms blue batlike network

Microfilaments

Type of Cytoskeleton where it is made of fibrous subunits. it helps form desmosomes and provide internal guy wires to resist pulling forces on the cell.

Intermediate filaments

Type of Cytoskeleton where it is made of repeating subunits of protein tubulin. it determines the overall shape of organelles. important for cell division.

Microtubules

Rod-shaped bodies made of microtubules

Centrioles

Direct formation of mitotic spindle during cell division

Centrioles

Not found in all cells & Used for movement

Cellular Projections

“eye lashes”- whiplike cellular extensions that moves materials across the cell surface

Cilia

___propels the cell. the only one of this in the body is the sperm

Flagellum

Cells that connect body parts

Fibroblast and Erythrocyte

Cells that cover and line body organs

Epithelial cell

cell that move organs and body parts

Skeletal muscle cell and Smooth muscle cell

cell that stores nutrients

fat cell

cell that fights disease

macrophage cell

cell that gathers information and controls body functions

nerve cell

cells of reproduction

Ovum and Sperm

movement of substance into and out of the cell

Membrane Transport

No energy is required to transfer

Passive transport

The cell must provide metabolic energy to transfer

Active transport

homogeneous mixture of two or more components

Solution

dissolving medium

Solvent

components in smaller quantities within a solution

Solutes

nucleoplasm and cytosol

Intracellular fluid

fluid on the exterior of the cell

Interstitial fluid

-The plasma membrane allows some materials to pass while excluding others

-This permeability includes movement into and out of the cell

Selective Permeability

-Particles tend to distribute themselves evenly within a solution

-Movement is from high concentration to low concentration, or down a concentration gradient

Diffusion: passive

Type of diffusion that’s an Unassisted process & Solutes are lipid-soluble materials or small enough to pass through membrane pores

Simple diffusion

Type of diffusion that’s simple diffusion of water

-Highly polar water easily crosses the plasma membrane

Osmosis

Type of diffusion where substances require a protein carrier for passive transport

Facilitated diffusion

-Water and solutes are forced through a membrane by fluid, or hydrostatic pressure

-A pressure gradient must exist

-Solute-containing fluid is pushed from a high pressure area to a lower pressure area

Filtration: passive

Transport substances that are unable to pass by diffusion

They may be too large

They may not be able to dissolve in the fat core of the membrane

They may have to move against a concentration gradient

Active Transport

-Amino acids, some sugars and ions are transported by ___

-ATP energizes protein carriers, and in most cases, moves substances against concentration gradients

Solute pumping: active

Exocytosis and Endocytosis

Bulk transport

-Moves materials out of the cell

-Material is carried in a membranous vesicle

-Vesicle migrates to plasma membrane

-Vesicle combines with plasma membrane

-Material is emptied to the outside

Exocytosis

Extracellular substances are engulfed by being enclosed in a membranous vesicle

Endocytosis

Type of endocytosis that’s cell eating

Phagocytosis

Type of endocytosis that’s cell drinking

Pinocytosis

major period of the cell where: Cell grows & carries on metabolic processes

Interphase

major period of the cell where: Cell replicates itself & Function is to produce more cells for growth and repair processes

Cell division

-Genetic material duplicated and readies a cell for division into two cells

- Occurs toward the end of interphase

- DNA uncoils and each side serves as a template

DNA Replication

Division of the nucleus & Results in the formation of two daughter nuclei

Mitosis

Division of the cytoplasm & Begins when mitosis is near completion & Results in the formation of two daughter cells

Cytokinesis

Stage of Mitosis where: No cell division occurs & The cell carries out normal metabolic activity and growth

Interphase

Stage of Mitosis where: First part of cell division & Centromeres migrate to the poles

Prophase

Stage of Mitosis where: Spindle from centromeres are attached to chromosomes that are aligned in the center of the cell

Metaphase

Stage of Mitosis where: Daughter chromosomes are pulled toward the poles & The cell begins to elongate

Anaphase:

Stage of Mitosis where: Daughter nuclei begin forming & A cleavage furrow (for cell division) begins to form

Telophase

DNA segment that carries a blueprint for building one protein

Gene

The Building materials for cells & Act as enzymes (biological catalysts)

Proteins

___is essential for protein synthesis

RNA

Transfers appropriate amino acids to the ribosome for building the protein

Transfer RNA /tRNA

Helps form the ribosomes where proteins are built

Ribosomal RNA/rRNA

Carries the instructions for building a protein from the nucleus to the ribosome

Messenger RNA/mRNA

Transfer of information from DNA’s base sequence to the complimentary base sequence of mRNA

Transcription

Base sequence of nucleic acid is translated to an amino acid sequence

Translation

___ are the building blocks of proteins

Amino acids

Groups of cells with similar structure and function

Tissues

Tissues found in Body coverings & Body linings

Epithelial Tissues

Tissues for: Protection, Absorption, Filtration, & Secretion

Glandular tissue

have no blood supply

Avascular