Biology Cell Packet 2 Quiz Flashcards-Kowalski

Define Somatic Cells

Cells found In Body(Body Cells)

What Does Cell Division Do To The Number Of Somatic Cells?

It increases the number of somatic cells

Define Mitiosis

Division of the Nucleus of the Cell(Splits genetic material inside nucleus between two new daughter cells)

Define Cytokinesis

division of the cytoplasm(after cell splits into two-starts during Telophase)

Define Apoptosis

A programmed cell death that decreases number of total cells

Does Apoptosis occur throughout your entire life?

Yes.

When/Why Does Apoptosis Occur?

Occurs when the cell detects that it is abnormal, it happens to prevent abnormal cells from spreading through Mitotic Cell Division.(Cancer Cells don't undergo Apoptosis)

Why is it important that we undergo cell division throughout our lives?

So we can grow/develop as well as repair our old/worn out cells

Define Mitotic Cell Division

The Division of somatic cells to increase total number of somatic cells utilizing the processes of Mitosis and Cytokinesis.

What are Gamete?

Sex Cells(sperm and egg)

Define Cell Cycle

All the events that occur between the time a cell divides and the time its daughter cells divide.

What's The Longest Phase in the Cell Cycle?

Interphase

What happens during interphase?

The cell works like normal and preperations are made for division.

What are The Stages of Interphase in Chronlogical Order)?

G1(Gap 1) Stage, S(Synthesis) Stage, G2(Gap 2) Stage

What happens in the G1 stage of Interphase?

Organelle Number Doubles, Materials for division are collected

What Happens in the S Stage of Interphase?

DNA Replication

What Happens in the G2 stage of Interphase?

Synthesis(Making) of proteins needed for division

What is G0 Phase?

A Stage of Interphase that occurs after G1 stage in which the cell doesn't divide. Can be temporary or permanent. -Ex. Mature Brain Cells

What Form is DNA in during Interphase and Mitotic Phase?

Interphase-Chromatin Form
Mitiotic Phase-Chromosome Form

When Does Mitotic Stage Occur?

After Interphase

What Two Proccesses occur during Mitotic Stage?

Mitosis and Cytokinesis

Mitotic Cell Division Occurs During What Stage?

Mitotic Stage

For all stages in the Cell Cycle To Progress, what protein must be present?

Cyclin

List 3 Checkpoints In Cell Cycle in Chronlogical Order

G1(Gap 1) Checkpoint, G2(Gap 2) Checkpoint, M(Mitotic) Checkpoint

What happens in all 3 Checkpoints in Cell Cycle(Chronologically)?

G1 Checkpoint-protein p53 stops cell cycle if DNA is Damaged

G2 Checkpoint-cell cycle stops if DNA is not done replicating or it is damaged

M Checkpoint-stops cell cycle if all chromosomes are not aligned

What protein stops cell cycle if protein is Damged in the G1 Checkpoint?

protein p53

If DNA is damaged in the G1 Checkpoint what happens?

Apoptosis

What occurs in Apoptosis?

A progressive series of events resulting in cell destruction

Apoptosis is mediated by two sets of enzymes called what?

Caspases

What do the two sets of Caspases do in Apoptosis?

One set initiates the events of Apoptosis, the other activates enzymes that digest the cell

What are the exact events that occur in Apoptosis?

cell rounds up
loses contact with surrounding cells
Nucleus Breaks Up
Chromatin Condenses
DNA Fragments
Blisters Form in Plasma Membrane
Cell Undergoes Fragmentation
Cell Fragments are formed

What are fragments of DNA called that are created by Apoptosis?

blebs

What are fragments of cells called that are created by Apoptosis?

Cell Fragments

Define Chromatin

Tangled Mass of threadlike DNA in a nondividing cell

stable, messy, and not good for cell division

Define Chromosomes

condensed rod-shaped DNA molecules during Mitotic Cell Division

unstable, packed/organized, and good for cell division

Define Diploid

Somatic Cells that contain a full set of chromosomes in pairs-Human somatic cells have 23 pairs(46 total chromosomes)

Define Haploid

Gametes with a half set of chromosomes-Human gametes have 23 chromosomes(no pairs)

What is the mathematical expression used to compare diploids and haploids in terms of the number of chromosomes?

Diploids-2N
Haploids-N

N->Number of chromosomes

What does mitosis make?

duplicate somatic daughter cells

What type of division is Mitosis?

Nuclear Division

What happens to the chromsome number of a cell before and after Mitosis?

it stays the same

Duplicated Chromosomes are composed of what?

2 sister chromatids held together by a centromere

What happens to the centromere and sister chromatids after Mitosis?

Centromere- gets split
Chromatids- split and become daughter chromosomes

Before/During/After mitosis, the cell is a haploid or diploid?

Before/During/After Mitosis, the cell is always a diploid

What is a Centrosome?

2 centrioles

How many centrosomes/centrioles in a cell?

2 centrosomes(4 centrioles)

List All phases of Mitosis in chronological order

Prophase, Metaphase, Anaphase, and Telophase

What Happens in Prophase of Mitosis?

nuclear membrane dissapears, centrosomes migrate to poles, Centromere start to divide(but is still holding sister chromatids together), and spindle fibers appear

What Happens in Metaphase of Mitosis?

Chromsomes line up at equator, and attatch to spindle fibers

What Happens in Anaphase of Mitosis?

Centromeres actually divide into two, spindle fibers pull sister chromatids to opposite poles of the cell(chromosomes double), and preparation for cytokinesis begins

What Happens in Telophase of Mitosis?

2 Nuclear membrane forms, spindle fibers disappear, cytokinesis actually occurs

What is an indicator that cytokinesis has started to occur in an animal cell?

the formation of cleavage furrow

How can you tell if the cell is still in Interphase?

if the DNA in the nucleus is in chromatin form(can tell if nucleus is a solid color when looked closely at)

Where Do Cells Divide in Plants?

In Merismatic Tissues

What is The Difference between the phases in mitosis in animals vs plant cells?

No Difference(Same Phases)

What organelles relating to cell division does a plant cell not have that animal cells do have?

Centrioles and asters(centrioles+ spindle fibers)

What are asters?

centrioles and their associated spindle fibers

Since plant cells cannot be pulled apart to divide, what happens instead?

A flat/small disk is formed between the two daughter cells called a cell plate.

For cytokinesis to occur in a plant cell, what must occur first?

the formation of the cell plate

How does the cell plate form?

The golgi apparatus produces vesicles containing neccesary materials to build the cell plate and sends those vesicles to the center of the plant cell which are used to build the cell plate.

How does the cell plate eventually become a cell wall to officially divide the plant cell into two?

by gradually fusing with the existing cell wall as it keeps getting materials from the golgi apparatus.

How do the new plasma membranes form in a plant cell after Mitosis occurs?

by collecting vesicle membranes from vesicles that were sent to cell plate and using those mebranes to build a new plasma mebrane for each daughter cell.

While cytokinesis occurs in a plant cell, what other process is occuring at the same time?

the transformation of the cell plate into a cell wall

Where does cleavage furrow form?

in animal cells between the daughter nuclei/cells

What happens to the contractile ring of the cleavege furrow as the cell splits?

the contractile ring of cleavage furrow contracts until separation is complete

What is cleavege furrow?

the space between daughter nuclei during seperation

What is the contractile ring?

a series of proteins that wrap around the center of the two daughter cells and slowly pinches itself until seperation is complete and the cell splits in two

The more the contractile ring contracts what happens to the cleavege furrow?

the cleavege furrow increases in size

How long does it take a normal cell to divide?

5-6 hours

How long does it take a bacterial cell to divide?

20 minutes

What is cell division in prokaryotic cells called?

Binary Fission

How many chromosomes do prokaryotic cells have?

One

Before a prokaryotic cell divides, what happens to its cell shape?

it lengthens/elongates to twice its length

How does a prokaryotic cell split into two?

it's cell mebrane grows inward until division is complete(think pinching a bubble but instead of popping it splits into two)

Define meiosis

cell division that results in 4 daughter cells(gametes)

How many daughter cells are produced as a result of meiosis?

4 daughter cells

How many divisons occur in meiosis?

2 divisions

Meiosis results in diploid or haploid cells?

haploid cells

At the beginning of meiosis are cells diploid or haploid?

diploid

What are homolgues?

pairs of chromosomes(not random, chromosome 1 is paired with another chromsome 1, 2 with 2, 3 with 3, etc.)

What is it called when homologues line up side by side at the equator(vertically) of the cell?

Synapsis

When pairs seperate, each daughter cell recieves what?

half the pair(one member of pair)

Are cells diploid or haploid after Meiosis 1 ?

haploid

When chromsome 1 pairs with another chromsome 1, are they genetically the same?

no, the may be the same chromosome, but one came from mom and the other came from dad containing different genes.

Can the dipoid cell at the start of meiosis be any random cell?

no, they have to be a primary spermatocyte or a primary oocyte(depending on gender)

The cells produced after Meiosis 1 and Meiosis 2 both are genetically the same or different?

every daughter cell is different/unique

Meiosis 2 is very similar to what other process?

Mitosis

What happens in Meiosis 1?

synapsis occurs, pairs seperate and each daughter cell recieves 1/2 the homolgue pair, cells become halploid

What happens in Meiosis 2?

MITOSIS

centromeres divide
sister chromatids migrate to opposite poles to become individual chromsomes
4 daughter cells are still haploid
each chromsome is now composed of only 1 chromatid(like it should be originally)

What are the two ways genetic recombination occurs?

Crossing Over, Independent Alignment

What does genetic recombination do and why is it important?

Promotes genetic variability(makes everyone unique), which strengthens our species

Define Crossing-Over

the exchange of segments of DNA between homologues

Define Independent Alignment

random assortment of homologues(is it left or right of vertical equator)

How can we calculate the number of possibilities for each daughter cell's DNA leaving out crossing over?

2^(number of chromosomes)-----ex. human gametes are 2^23 so 8,388,608 possiblities

Are all eggs and sperm cells gentically the same?

no, they are ALL gentically different

what is pollen?

plant sperm

When does crossing over occur?

during synapsis

Does crossing over always happen?

no, it can happen but it doesn't always happen(random tangling up of nonsister chromatids)

What are phases of Meiosis 1?

Prophase 1, Metaphase 1, Anaphase 1, Telophase 1

What Happens in prophase 1?

nuclear membrane breaks down
synapsis
crossing over(if it does happen)

What Happens in metaphase 1?

independant alignment
homologues pairs line up at equator

What Happens in anaphase 1?

pairs pull apart
independent assortment into daughter cells

What Happens in telophase 1?

cytokinesis occurs
cell splits-2 daughter haploid cells are produced

indpendant alignment vs independant assortment

independent alignment is which chromosome is left or right of vertical equator

indpendent assortment is which independant sister chromatid goes to which daughter cell

what is the period of time between meiosis 1 and meiosis 2 called?

Interkinesis

What are all the phases in meiosis 2?

Prophase 2, metaphase 2, anaphase 2, telophase 2

What Happens in prophase 2?

cells have 1 member of each homologues pair

What Happens in metaphase 2?

Chromosomes line up at the equator.

What Happens in anaphase 2?

centromeres divide and daughter chromsomes migrate to opposite poles

What Happens in telophase 2?

Nuclei form, cytokinesis occurs

Starting with 1 cell, how many cells undergo Meiosis 2?

2 cells

What does Meosis 2 create?

4 Haploid Daughter sex cells(gamete-->sperm or egg) that are all genetically different from eachother

When does crossing over happen?

prophase 1 of meiosis 1

when does independant alignement occur?

metaphase 1 of meiosis 1

Define nondisjunction

either failure of homologous chromosomes to seperate during anaphase 1 or failure of sister chromatids to seperate during anaphase 2

what is an example of nondisjunction?

down syndrome with nondisjunction in chromosome #21

what does nondisjunction cause?

various syndromes that stem from an abnormal number of chromosomes

When fertilization occurs, offspring are ALWAYS what?

genetically unique

in both meiosis and mitosis, how many times does DNA replication occur?

once at the start prior to both processes

How many divisions in meiosis vs mitosis?

meiosis-2 divisions
meiosis-1 divison

how many daughter cells are produced after meiosis/mitosis?

meiosis-4 daughter cells
mitosis-2 daughter cells

what is the major difference between daughter cells of meiosis and daughter cells of mitosis?

meiosis-haploid
mitosis-diploid

what is genetic difference between meiosis daughter cells and mitosis daughter cells?

meiosis-all genetically variable
mitosis-gentically identical

in a diagram, you know that mitosis/meiosis is not finished when the chromsomes are...?

in an x-shape

The human life cycle requires what?

mitosis AND meiosis

what is meiosis in males and females called?

females-oogenisis
males-spermatogenesis

how does a zygote grow into a child?

through the repeated process of mitosis

what process is used to repair ourselves throughout life?

mitosis

when you stop releasing eggs what is it called?

Menopause

Spermatogenesis begins with a __________ undergoes __________ becomes 2 __________ undergoes __________ becomes 4 __________ and they mature eventually into __________

primary spermocyte, meiosis 1, secondary spermocytes, meiosis 2, spermatids, sperm

What is the only diploid cell that can make sperm?

A primary spermocyte

Oogenesis begins with a __________ and becomes a __________ and a _________ and becomes a __________ and a _________

primary oocyte, secondary oocyte, polar body, oocyte, polar body

Oogenesis makes how many polar bodies?

2(sometimes 3 if 2nd one splits into two)

What happens to all polar bodies made during oogenesis?

they disentegrate

What do polar bodies contain?

the half set of chromosomes that are not needed

what is the only diploid cell that can make an oocyte?

a primary oocyte

Spermatogenesis and oogenesis both utilize which process?

Meiosis

When does spermatogenesis begin and end?

begins at puberty and continues throughout entirety of life for a male

Spermatogenesis makes how many sperm per primary spermatocyte?

4 sperm(which makes sperm abundant in body)

When does oogenesis begin and end?

begins before birth, then resumes in a cyclic pattern until menopause for females

When do oocytes start being released?

puberty

Oogenesis results in how many oocytes and polar bodies?

1 oocyte and 2-3 polar bodies

The division of expelled chromosomes in the first polar body vs the second are equal or unequal?

unequal

What recieves the most of the cells contents in oogenesis?

the ovum