New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Set 2 of Unit 4 Notes

by: Danielle Francy

Set 2 of Unit 4 Notes Bio 190

Marketplace > Towson University > Biology > Bio 190 > Set 2 of Unit 4 Notes
Danielle Francy

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Notes from this week.
Intro Biology for Health Professions
Joseph Velenovsky
Class Notes
Bio 190
25 ?




Popular in Intro Biology for Health Professions

Popular in Biology

This 7 page Class Notes was uploaded by Danielle Francy on Thursday April 14, 2016. The Class Notes belongs to Bio 190 at Towson University taught by Joseph Velenovsky in Fall 2015. Since its upload, it has received 4 views. For similar materials see Intro Biology for Health Professions in Biology at Towson University.


Reviews for Set 2 of Unit 4 Notes


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 04/14/16
Unit 4 Notes    Metaphase:  ● ***Mitotic spindle fully formed and functional  ● Poles are completely at opposite ends of the cell  ● Chromosomes converge on the metaphase plate  ● Metaphase plate is an imaginary area equidistant between the two ends of the spindle  ● Centromeres are lined up on the metaphase plate  ● Within each chromosome, the kinetochores face opposite poles  ● Microtubules attached to a particular chromatid are from one pole; its sister    Anaphase:  ● Sister chromatids are separated as the two centromeres of each chromosome come  apart  ● Upon this separation, each sister chromatid is labeled a daughter chromosome  ● Kinesins and Dynein walk daughter chromosomes centromere first along microtubule  towards opposite poles of the dividing cell  ● At the same time, spindle microtubules attached to kinetochores shorten  ● Spindle microtubules not attached to kinetochores lengthen   ● Poles are moved farther apart    Telophase:  ● Cellular expansion or elongation that started in anaphase continues  ● Daughter nuclei appear at opposite ends of the cell  ● Nuclear envelopes form around the chromosomes at each pole  ● Telophase is reverse of prophase  ● Chromatin structure starting   ● Presence of a nuclear envelope  ● Shrinking of the mitotic spindle  ● By the end of telophase, chromosomes are nearly coiled as chromatin  ● Mitotic spindle has disappeared  ● Mitosis is complete after telophase  ● Defined as the equal division of one nucleus into two genetically identical daughter  nuclei  ● Still undergo cytokinesis  ● Cytokinesis occurs often concurrently with telophase    Cytokinesis:  ● Two daughter cells completely separate after the end of mitosis  ● Begins concurrently with telophase  ● Animal and plant cells undergo cytokinesis differently          Cell Walls in Plant Cells:  ● Process called cleavage  ● First sign of cleavage is the cleavage furrow  ● Shallow indentation  ● Ring of microfilaments made of Actin  ● Associated with myosin  ● Interacting causes contractions  ● Cleavage furrow deepens and eventually splits the parent cell into two distinct daughter  cells  ● Cytokinesis is the division of the cytoplasm; the division of the nucleus is associated with  mitosis  ● During telophase, vesicles containing cell wall material (cellulose, etc.)  ● Gather at the middle of the parent cell  ● Vesicles fuse forming a membranous disk called the cell plate  ● Cell plate grows outward adding more cell wall material from vesicle fusion  ● Eventually, the cell plate fuses with the plasma membrane  ● Cell plate’s contents join the parental cell wall  ● Two daughter cells      ● Control of timing of cell division is important  ● Skin cells vs. liver cells  ● Mammalian cells  ● Growth factors  ● Essential nutrients  ● Secreted protein that stimulates other cells to divide  ● Platelet­ derived growth factor  ● Injury to skin  ● Blood platelets release growth factor  ● Rapid growth of connective cell tissue to seal the wound  ● Vascular endothelial growth factor (VEGF)  ● Stimulates new blood vessels during fetal development and after injury  ● VEGF production    Physical factors:  ● Density­dependent inhibition  ● Crowded cells stop division  ● Animal cells form single layer  ● When space is filled and contact occurs between cells, division stops  ● If cells are removed, space fills again  ● Cell­surfaced proteins between adjacent cells touch  ● Inhibition of cell division  ● Anchorage dependence; animal cells  ● Must be in contact with solid surface to divide  ● Culture dish; ECM    Animal Cells:  ● Normally anchored in a fixed position  ● Nutrients supplied by blood  ● Usually don’t divide unless signaled by other cells  ● Growth factors  ● Cell cycle controlled by control system  ● Cyclins and cyclin­ dependent kinases  ● Controls progression of cell cycle  ● Progression is not automatic  ● Proteins of the control system determine progression    Checkpoints:  ● Critical  ● Need specific signals  ● G1, G2, M  ● Progress cell cycle  ● Stop progression  ● Intracellular signals  ● Extracellular signals  ● Detected by control system determine if progression should occur  ● Key cellular processes  ● Environmental conditions outside the cell  ● First gap checkpoint is the most important  ● If signal never arrives, switch to G0  ● Mature muscle cells  ● Control system at G1 checkpoint  ● Growth factor  ● Changes in each protein molecule  ● Ex: phosphorylation  ● Cyclins, etc. not located in one place, but throughout cell  ● Signals can override the brakes  ● Progression through cell cycle    Disease of the Cell Cycle:  ● Mutation in one or more genes for proteins in control system  ● Immune system destruction  ● Evasion  ● Benign tumor  ● Malignant tumor  ● Spreads to other tissues  ● Cancer  ● Metastasis  ● Carcinomas  ● External/internal coverings  ● Intestinal lining  ● Skin  ● Sarcomas­ supporting tissues  ● Bone muscle, leukemias, lymphomas, blood forming tissues, bone marrow, spleen,  lymph nodes  ● Loss of cell cycle control  ● Not influenced by normal signals  ● Proceed through checkpoints even if growth factors not present  ● Can synthesize growth factors themselves  ● If they do stop dividing (IF) it is random not at checkpoints  ● Immortal­ as long as nutrients present  ● Normal mammalian cells stop after 20­50 times  ● Local tumors removed surgically  ● Radiation damages DNA  ● Cancer cells rather than normal cells ideally  ● Cancer cells hypothesized to have lost ability to repair DNA damage (all they do is  divide)    Normal Cells Side Effects:  ● Radiation can cause sterility  ● Metastatic tumors­chemotherapy  ● Drugs disrupt specific steps in the cell cycle  ● Taxol freezes the mitotic spindle after it forms  ● Stop division at metaphase  ● Vinblastin  ● Prevents mitotic spindle formation entirely    Side effects:  ● Effects on normal cells that rapidly divide  ● Intestinal cells, nausea, hair loss, hair follicle cells, immune cells  ● Susceptibility to infection      ● Differential selective gene expression in response to both internal and external signals  ● Turn genes on and off  ● Multicellular eukaryotes require cellular differentiation  ● Specialized in structure and function        Chromosomes:  ● Tightly packaged DNA   ● Found only during cell division  ● DNA is not being used for macromolecule synthesis    Chromatin:  ● Unwound DNA  ● Found throughout interphase  ● DNA is being used for macromolecule synthesis    Somatic Cells:  ● Body cells  ● 46 chromosomes  ● Metaphase of mitosis  ● 2 sister chromatids  ● Arranged into matching pairs based primarily on size  ● Centromere position  ● Banding pattern  ● 23 pairs of duplicated chromosomes  ● Homologous chromosomes  ● Homologs  ● Genes are located at the same loci  ● Allelic versions may be different  ● Locus, banding patterns  ● In females, 46 chromosomes are arranged neatly into 23 pairs of homologous  chromosomes  ● In males, X and Y (partly homologous)  ● Determine sex and other functions  ● Autosomes    Human Life Cycle:  ● Two sets of chromosomes in each person; one from mother and one from father  ● Species that reproduce sexually, share this characteristic with humans  ● Diploid  ● Somatic cells contain pairs of homologous chromosomes  ● Total number is diploid number (2n)  ● Humans diploid number = 46  ● 2n = 46  ● Gametes= egg and sperm  ● Single set of chromosomes  ● 22 autosomes  ● 1 sex chromosome  ● Either X or Y  ● All eggs have X  ● Sperm determines sex of offspring  ● Haploid cells  ● One chromosome of each homologous pair  ● Homologous number = 23  ● N = 23  ● Haploid sperm, haploid egg  ● Fertilized egg  ● Fertilization  ● Zygote  ● Two sets of homologous chromosomes  ● Diploid  ● One set from each parent  ● Development occurs    Sexual Reproducing Organisms:  ● Alternation of diploid and haploid stages  ● Good mechanism because gametes (haploid) prevent chromosome number from  doubling every generation  ● Produced by meiosis  ● Only in reproductive organs  ● Testes and ovaries in humans  ● Mitosis produces daughter cells with same number of chromosomes  ● ***Meiosis reduces the chromosome number by half  ● Duplication during interphase  ● Separate haploid daughter cells  ● Still doubled  ● Separation of sister chromatids  ● Four daughter cells are haploid  ● Only a single chromosome from parental homologous pair  ● Haploid gametes in diploid organisms  ● Two haploid gametes combine  ● Restoration of diploid state  ● Prevents doubling of genetic material each generation  ● Before meiosis, just like mitosis, chromosomes duplicate  ● Meiosis I, Meiosis II  ● Two rounds of cellular division  ● Four daughter haploid cells  ● Inherited  ● ***Prophase I and crossing over  ● Similar to mitosis      Interphase:  ● Chromosomes duplicate  ● Each chromosome consists of two genetically identical sister chromatids  ● Centrosome has also duplicated  ● By the end of interphase  ● Early prophase I  ● Chromatin coils up  ● Individual chromosomes are visible  ● Synapsis  ● Homologous chromosomes (each made of 2 sister chromatids) are paired  ● Four chromatids tetrad   


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

Kyle Maynard Purdue

"When you're taking detailed notes and trying to help everyone else out in the class, it really helps you learn and understand the I made $280 on my first study guide!"

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.