Exam 2 KIN223

Define Cytology

Study of cells

Describe the Light Microscope

2D image

Via visible light

Mag:40x,100x,1000x

Stained with colored dyes

Describe the Electron Microscope

Uses Electrons to illuminate

Stained with HEAVY metal

Describe the Transmission Electron microscope

2D image

Mag:5000x

Electron beam

Define the scanning electron

3D Image

Mag: 3000x

Which microscope has 2D images?

Light

Transmission

From smallest to largest what is the cell sizes? (HINT: REFENSES TO HUMAN HEIGHT/OSTRICH EGG)

Atom → Small molecules → Large macromolecules → ribosomes → viruses → Mitochondria → Red Blood cell → Most plant/animal cells → Human ooctye → Ostrich egg → some muscle and nerve cells → human height

What are some irregular shaped cells?

Nerve cells

What are the biconcave disc shaped cells?

Red Blood cells

What are some cube shaped cells?

Kidney tubule cells

What are some Column shaped cells?

Intestinal lining cells

What are some spherical shaped cells?

Cartilage cells

What are some cylindrical shaped cells?

Skele muscle cells

What are the 3 common structures of a cell?

Plasma membrane

Nucleus

Cytoplasm

I create the outer, lining barrier that separated the internal contents of a cell

I can have modified extensions like Cilia, flagellum, microvilli

What am I?

Plasma membrane

I am the LARGEST structure

I am enclosed by a nuclear envelope

Inside: DNA (mostly) Nucleoplasm, dark staining body aka nucleolus

Nucleus

I am a general term for all cellular contents

I am located in between the nucleus and plasma membrane

I have 3 primary contents: Cystol, Organelles, Inclusions

Cytoplasm

Compare/contrast membrane bound organelles vs NON membrane bound organelles

Membrane- Enclosed, separates the organelles’ contents, includes the E.R, ex: golgi, lysosomes, peroxisomes, mitochondria

NON membrane- NOT enclosed, has: Proteins/ ribosomes, Within the cystol/external surface of E.R, ex: Centrsome, Proteasomes, cytoskeleton

What are some characteristics of inclusions?

NOT an organelle

Clusters of a single type of molecule

Ex: pigaments, nutrients stores

What are the cell functions?

Maintain integrity/shape of cells

Get nutrients and form chem. building blocks

get rid of waste

What are some of the lipid components of plasma membrane

Phospholipids

Cholesterol

Glycolipids

What is the Phospholipids’s function

Makes the phospholipid bilayer

Makes sure the cystol remains in the cell and interstitial fluid remains on the outside

What is the function of the cholesterol?

Strengthens the membrane/stabilize it at temp. extremes

What is the function of glycolipids

aka sugar antennae

Contribute to the glycocalyx

Where are integral proteins?

EMBEDDED within the phospholipid layer

Where are peripheral proteins?

NOT embedded within the lipid bilayer

Loosely attached

What are the 6 major roles by membrane proteins?

Transport proteins

Cell surface receptors

ID markers

Enzymes

Anchoring sites

Cell Adhesion Proteins

What are some of the different types of transport proteins?

Channels

Carrier proteins

Pumps

Symporters

Antiporters

In the anchoring site what is secured?

Secure the cytoskeleton to the plasma membrane

Define diffusion

Movement of ions/molecules down their concentration

Kinetic energy is random

Is dependent upon a concentration gradient

Spreads ions/molecules

If unopposed diffusion results in =

Which diffusion moves small/nonpolar?

Simple

Which diffusion moves charged ions/polar molecules

Facilitated

In simple diffusion describe the process

The movement does not need help

Movement is dependent on the concentration

Impaired respiratory/cardiovascular function can alter the gradient

Which diffusion needs a carrier?

Faciliated

What helps the facilitated diffusion?

Plasma membrane proteins

Describe the 2 types of facilitated diffusion?

Channel medicated diffusion: Small ions via channel leak (opened) or Gated channel (closed)

Carrier-mediated diffusion: movement of polar molecules, needs a carrier proteins, uniporter=one being transport

Define Osmosis

passive moment of water thru semipermeable

Passive transport

Water follows solutes

Define aquaporins

integral proteins that are water channels

Define Osmotic pressure

The pressure exerted by movement of water across semipermeable membrane due to diff in water concentration

Define hydrostatic pressure

Pressure exerted by fluid on the inside wall of its container

Define tonicity

Ability of solution to change the vol/pressure of the cell by osmosis

What happens to cell in a isotonic solution

Fluid stays the same

no movement

What happens in a hypotonic solution?

Water comes in the cell → hemolysis (CELL GROWS)

In: More concentration

Out: Less concentration

What happens in a hypertonic solution

Water leaves the cell → crenation (CELL SHRINKS)

In: LESS concertation

Out: MORE concentration

Compare and contrast Primary vs Secondary transport

Primary: Uses energy derived directly from breakdown of ATP, provides the phosphate group → change of protein shape and movement of solutes across membrane

Secondary: involves the movement of substance down the concentration gradient aka kinetic energy, symport-2 substance in same direction, antiport- 2 substances in opp direction

Define vesicular transport

Bulk transport

Uses a vesicle

Define exocytosis

Secreted from cell

Define endocytosis

Cellular uptake of large substances/large amounts of substances from external environment into cell

Which vesicular transport is used for uptake nutrients/extracellular debris for digestion, retrieval of membrane regions

Endocytosis

Which vesicular transport is use for large macromolecules

exocytosis

What are the 3 types of endocytosis

phagocytosis, pinocytosis, receptor mediated endocytosis

Define phagocytosis

Cellular eating

Define pinocytosis

Cell drinking

Receptor mediated

To bind molecules

Define membrane potential

Electrical charge difference shows protentional energy

Define resting membrane potential

When a cell is at rest

What are the cellular conditions for a resting membrane potential

1. Cell has an unequal distribution of ions/charged molecules

   Cystol closes to contain K+ than the surrounding interstitial fluid

2. Relative amounts of post/neg charged are unequal distributed

   More positive on the outside than the inside

   Difference in charge are measured by electrodes

Explain the role of K+ concerning RMP

The most important

Loss of K+ = neg charged structure

Movement is opposed by the gradient

Positive charge repeals the movement

Neg charged attacks the K+

Movement is facilitated by the chem concentration but opposed by the electrical gradient

Explain the role of NA+

Sodium diffusion into the cell happens when K+ is lost

Dependent on the electrochemical gradient

The movement = inside being more positive

If Na+ moves in what happens to the K+?

K+ moves out

What is the primary function of the immune system?

Make contact with unhealthy cells and kill em

What is an example of a cell communication via direct contact?

egg + sperm

Why do we need direct contract for cell communication?

Replacing damaged tissues

Making a baby

What is involved for direction contract for our body cells to communicate with our immune cells?

Glycocalyx

How do cells know which are healthy vs unhealthy (involves direct contact)

By seeing if the same pattern of sugars of the glycocalyx are the same as the body cells

What are the 3 general mechanisms of a response to binding of a ligand with a receptor

Channel-linked receptors

Enzymatic receptors

G protein coupled receptors

Describe the Channel Linked receptor

Permits ion passage

Needed to start electrical changes to the resting membrane in the skeletal, cardiac, and nerve cells

Describe the enzymatic receptors

Work as a protein kinase enzymes and are started to directly phosphorylate other enzymes

Provides a mechanisms for modding enzymatic activity in response to external signals

Describe the G protein receptors

Involves protein kinase activation that are started indirectly from the g protein which serves as an intermediate molecule

what are the main functions of the membrane bound organelles of a cell?

Rough E.R

Smooth E.R

Golgi

Lysosomes

Peroxisomes

Mitochondria

Which organelles make up the endomembrane system? What is their function?

Rough E.R

Smooth E.R

Golgi

Lysosomes

Peroxisomes

Function: TRANSPORT

Describe the Endoplasmic reticulum aka E.R

An extensive and interconnected network

Varies in shape but has one continuous lumen

Is a point of attachment for both ribosomes and different types of enzymes

Describe the ROUGH E.R

Has a studded like texture because of the ribosomes

What is the ROUGH E.R’s function?

ALL ABOUT PROTEINS

Synthesis: Protein for secretion, incorporation into plasma membrane, and as enzymes within lysosomes

Processing molecules: Mods proteins and store proteins

Organelle formation: Helps make peroxisomes

Vesicle formation: Makes transport vesicles for shipping of proteins to golgi for more mods

Describe the SMOOTH E.R

No ribosomes

Looks just like the rough E,R but no studs

What does the SMOOTH E.R do

ALL ABOUT LIPIDS!

Synthesis: Lipid synthesis

Processing molecules: Carbohydrate metabolism

Detoxi: detox drugs, alcohols, poisons

Vesicle formation: Makes transport vesicles for shipment

Describe the Golgi

Looks like a pancake

Has transport vesicles outside of the pancake

What does the golgi do?

POST OFFICE

Synthesis: Forms proteoglycans

Processing molecules: Mods/stores proteins

Organelle Formation: Syntehsis digest enzymes for lysosomes

Vesicle formation: Creates secretory vesicles for delivering parts of the plasma membrane and letting the contents go from the cell via exocytosis

Describe the step by step process of synthesis, mods, shipping of proteins

(FIGURE 4.23)

1. Rough ER synthesizes with a protein that is let go in a transport vesicle

2. Vesicles from ROUGH go to Golgi

3. Vesicle combos with Golgi

4. Proteins are modded as they move thru the golgi

5. Modded proteins are packaged and released within the secretory vesicle

6. S.V merges with the plasma membrane to either insert molecules or release contents via exocytosis, they also provide digestive enzymes to lyosomes

What is the function of the Lysosomes

CLEAN UP CREW!

Digestion: Breaks down molecules via endocytosis, removing damaged organelles/cellular parts (autophagy), and breaking down cellular components following a cell death (autolysis)

Are small, membrane enclosed, spherical sacs

Has digestive enzymes that are immersed in acid fluid

what organelle is this?

Lyosomes

Are small, membrane enclosed, spherical sacs

Has over 50 different enzymes

Peroxisomes

What is the function of Peroxisomes

ALL ABOUT FATS

Digestion: Breaks down molecules via hydrogen peroxide produced during the process

Synthesis: Makes certain types of lipids (bile salts, plasmalogens)

Describe the mitochondria

Oblong shaped

Has a outer mitochondrial membrane

Matrix inside (Has small dna)

Has a cristae

Inner mitochondrial membrane

What is the function of the mitochondria?

POWERHOUSE

Energy Harvesting: Eats organic molecules to create ATP via aerobic cellular respiration

Also functions with cell death

What are the NON membrane-bound organelles? (All end with -Some the Threesome)

Ribosomes

Centrosome

Proteasomes

Describe the Ribosomes

Have protein and RNA

Has 3 hollow areas called the A,P, and E sites

They are puzzle

What does the ribosome do?

Protein synthesis: Bound ones are destined to be incorporated into the plasma membrane and are exported from the cell or housed within lysosomes, FREE ones are for use within cell

Is close to the nucleus

Has a pair of perpendicular oriented cylindrical surrounded by proteins

What organelle is it?

Centrosome

What are the main functions of the centrosome?

Synthesis: Organizes microtubules and supports their growth in NON diving cells

Cell division: Direct formation of spindle fibers in diving cells

A large barrel shaped protein

Located in the cystol and nucleus

Which organelle am i?

Proteasomes

What is the function of the proteasomes?

THE MANAGER

Protein digestion: Degrades proteins that are damaged/no longer needed

Quality assurance: Control the quality of exported cell proteins

What are the 3 separated types of protein molecules from the cytoskeleton?

microfilaments

Microtubules

Intermediate filaments

What is the function of the cytoskele?

MOVEMENT!

Structural support/organization: maintains cell shape and organizes organelles, stabilizes desmosome cell junctions

Cell division: Separates chromosomes during cell division, splits cell into 2 daughter cells

Movement: Starts cytoplasmic streaming,, a track for movement for organelles/vesicles, helps with muscle contraction

What am I? (Cilia, Flagella , Or micovilli)

I am small, hair-like, that extends from exposed surfaces of some cells

Contains: Supportive microtubule proteins

Enclosed by the plasma membrane

Found in LARGE numbers of certain cells

(Ex: Respiratory passageways)

Cilia

What am I? (Cilia, Flagella , Or micovilli)

Hair-like, LONGER/WIDER

Usually when present there is only ONE

Function: Helps propel an entire cell (EX SPERM)

Flagella

T/F

Movement of Cilia/Flagella occurs thru microtubules within their core, a process that needs energy via splitting of atp molecules

T

What am I? (Cilia, Flagella, Or microvilli)

Shorter/wider

DENSELY packed, lack powered movement

Supported by microfilaments

Provides a more extensive plasma membrane surface for more EFFICIENT membrane transport

Microvilli

Fill in the blanks

(Cilia, Flagella, Or microvill

Just like as not all cells have _____ not all cells have _____

Just like not all cells have CILIA not all cells have MICROVILL

What are the 3 types of membrane junctions?

Tight

Desmosomes

Gap