biology 3201 unit 1 test 1 cellular reproduction

What is a gamete cell

Sex cell

what is a somatic cell

body cell

what is the cell cycle

The life cycle of a cell/the time it spends growing, functioning, dividing. Growth Stage/Interphase (G1 phase → S phase → G2 phase) → Division Stage/ Mitosis (PMAT)

what are the stages of mitosis

Paraphase, Metaphase, Anaphase, Telophase (Cytokenesis)

how is cytokineses different in plant and animal

Plant cells: do not have centrioles but do produce spindle fibers, plant cell wall does not produce a cleavage furrow rather a cell plate forms. 

Animal cells:  has centrioles with spindle fibers, produces a cleavage furrow

what is cancer

Cancer is the result of a genetic mutation in genes which control cell division. Cancer is uncontrolled cell division and the cell stage that is likely to be altered by this is the S stage.

name some treatments for cancer

Some methods for treatment are surgery, radiation therapy, chemotherapy, immunotherapy, targeted therapy, hormone therapy, stem cell transplant

***why must germ cells reduce their chromosome number by half during meiosis

The process is called reduction division. It's important because the function of a sex cell is to meet the other cell by reducing the number by half when fertilization takes place it allows diploitidy to be restored. We are not built on haploid chromosome numbers, but to get a diploid number reduction and division must happen to restore diploid number when sperm meets egg.

what are the stages of meiosis

Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, Cytokenesis, Prophase 2, Metaphase 2, Anaphase 2, Telophase 2, Cytokenesis

how does crossing over contribute to genetic variation

during prophase 1  synapses occurs (homologous chromosomes pair up) and during which non sister chromatids in a homologous pair may exchange pieces of their chromosomes to have different combinations of paternal and maternal chromosomes.

how does independent assortment contribute to genetic variation

Independent assortment: during metaphase 1 homologous chromosomes line up at the equator of the cell independently and randomly to each other so the resulting gametes have different combinations of paternal chromosomes and maternal chromosomes

how are mitosis and meiosis similar

both are processes of division of cells, use PMAT and use contribute to the continuity of life

how are mitosis and meiosis different

meiosis-gametes, mitosis-somatic, mitosis has one set of PMAT, meiosis has 2 sets of PMAT

what is spermatogenesis

 occurs in the male testes, begins with a diploid germ called a spermatogonium, following two stages of meiotic division- of which there is an equal division of cytoplasm between cells- four haploid spermatid cells are produced, spermatids migrate to the male epididymis to become sperm

what is oogenesis

occurs in the female ovaries, begins with with a diploid germ cell called oogonium, each oogonium divides to produce two primary oocytes, roughly 3 months after conception roughly two million primary oocytes can be found in the ovaries, each of these primary oocytes are suspended un prophase 1 of meiosis until puberty, every month after puberty one primary oocyte completes meiosis however there is a unequal distribution of cytoplasm producing one secondary oocyte and one polar body, secondary oocyte begins meiosis 2 and unequally distributes cytoplasm to create a second polar body and one egg/ova however meiosis 2 of the secondary oocyte doesn't complete until fertilization occurs

why is there an unequal distribution of cytoplasm during oogenesis

Because the secondary oocyte needs as much cytoplasm as possible when it turns into an ova/egg

what is the anatomy of a sperm cell

Tail (movement) → middle piece (mitochondria) → head (nucleus and acrosome)

what is asexual reproduction

a form of reproduction which requires one parent, offspring are genetically identical

what is sexual reproduction

A form of reproduction which requires two parents, involves fertilization of gametes, offspring are genetically unique

what are the advantages and disadvantages of asexual reproduction

Advantages: less energy, guaranteed offspring

Disadvantages: does not have genetic variety

what are the advantages and disadvantages of sexual reproduction

Advantages: has genetic variety

Disadvantages: takes more energy, not guaranteed

Define Spores

a reproductive cell able to develop into a new organism, spores are small and readily dispersed by the wind, spores are released by the parent body

Define binary fusion

when a bacterial cell reproduces it copies its DNA and then distributes one complete copy of  that DNA into each of two identical daughter cells

define budding

A new organism develops from an outgrown of the parent body and the new organism then separates to become an independent organism

Define vegetative reproduction

reproduction in plants, a new plant grows from the growth of a modified stem

define fragmentation

the development of a new species from a fragment of the parent species

define parthanogenesis

an unfertilized egg develops into an adult

What is DNA

deoxyribonucleic Acid

what is a chromosome made of

a long strand of condensed DNA, usually in its non-condensed form called chromatin

what are the two main stages of the cell cycle

growth and division

what happens in the G1 phase

rapid growth and metabolic activity

what happens in the S phase

DNA synthesis and replication

what happens in the G2 phase

Cell prepares for division

What are three reasons why cells must divide

1. growth 2. maintenance 3.repair

what is time mostly spent during the cell cycle

interphase

what is metabolic activity

energy “at rest → bodies use to work

***What is the purpose of G1 and G2 phase

to grow and function in preporation for cell division

***How are sperm cells and egg cells similar and different?

Sperm cells: produced in males, equal distribution of cytoplasm, does not start at birth 

Egg cells: produced in females, unequal distribution of cytoplasm, oogenesis starts at birth 

Similarities: haploid, found in gonads, contributes to repopulation

What are the two main processes in cell division

Mitosis and Cytokinesis

Is the mitosis continuous or ending

continuous

What is the difference between benign and malignant

benign tumors generally don't invade and spread, malignant cells are more likely to metastasize, or travel to other areas of the body

what are mutated genes called

oncogenes

what are gametes produced from

germ

what is a germ cell

any biological cell that produces gametes for organisms that reproduce sexually

***why must gametes possess 23 chromosomes

to maintain chromosome # from one gen to the next, embryos need 46

What are two key outcomes of meiosis

reduction division and recombination/genetic variety

what is interphase in meiosis

occurs before a germ cell goes through meiosis 1 and as a result the germ cell will go through G1, S, and G phases. Chromosomes will replicate producing a pair of identical sister chromatids held together by a centromere

ow many times will interphase happen in meiosis

ONCE

What is the rul to how homologous chromosomes line up in metaphase 1 and 2

There is no rule, homologous chromosomes line up randomly

what is another way of saying independent assortment (the rogers way)

Insurance policy for genetic variety

what is another term for a homologous pair

a tetrad

do individual chromosomes split

NO

Will DNA replicate again after telophase 1 of meiosis

NO

what are the three processes that ultimately ensure genetic variety in gametes

reduction division, independent assortment, crossing over

describe reduction division

a germ cell starts with 46 chromosomes. following meiosis gametes have only 23 chromosomes. As such, meiosis produces daughter cells that contain only half of the genetics of the parent

***describe independent assortment

during metaphase 1 homologous chromosomes line up at the equator of the cell independently and randomly to each other. No one side of the genetic equator is designated for the paternal or maternal chromosome in a homologous pair giving the resulting gametes different combinations of paternal and maternal chromosomes

***describe Crossing over

During prophase 1 synapsis occurs and homolgous chromosomes pair up. During this crossing over occurs and non sister chromatids in a homologous pair may exchange pieces of their chromosomes and end up with both paternal and maternal genes

What is a non-sister chromatid

two homologous but not identical chromatids

what are the gonods

testes and ovaries

what is the name for a diploid germ cell in spermatogenesis

spermatogonium

how many spermatid are produced after 2 stages of meiosis

4 and all 4 sperm are viable

when does sperm become mature

after developing a tail

where does sperm mature

in the epididymis

when does oogenesis begin in a female

at birth

what is the name of a diploid germ cell in oogenesis

oogonium

is there a finite or infinite number of eggs in a female

finite

how many oocytes does an oogonium produce

2 primary oocytes

what hormone is needed for meiosis 2 to begin in oogenesis

follicle stimulating hormone

when is follicle stimulating hormone released in oogenesis

at puberty

what is the role of the acrosome in a sperm cell

it produces enzymes used to penetrate the egg during fertilization

is an egg cell motile or non-motile

non-motile, it doesnt have a tail

describe an egg cell

a large amount of cytoplasm and a nucleus with a jelly coat that produces proteins that help guide sperm to egg and follicular cells provide proteins to the cell

what is the purpose of the jelly coat of an egg cell

it guides sperm to the egg

***If 800 000 sperm, how many parent cells divided

200 000

are both asexual and sexual reproduction successful strategies and why

both forms of reproduction exist and are used in nature by living things therefore they are successful strategies for reproduction

What is an example of binary fission

bacteria

what is an example of budding

hydra

what is an example of vegetative reproduction

strawberries

what is an example of fragmentation

potatoes and sea stars

what is an example of parthanogenesis

aphids and honey bees

what is an example of spores

fungi

BONUS what are the 6 categories of life

1. animals

2. plants

3. fungus

4. bacteria (non-extreme)

5. bacteria (extreme)

6. protists