Unit 7 biology study guide

Binary fission, Budding, Fragmentation, Parthenogenesis, Regeneration

Single parent cell doubles its DNA, then divides into two cells, EX: bacteria

Small growth on surface of parent breaks off, resulting in the formation of two individuals, EX: yeast and some animals

Organisms break into two or more fragments that develop into a new individual, EX: many plants, as well as some animals (like coral, sponges, and starfish)

An embryo develops from an unfertilized cell, EX: invertebrates, as well as in some fish, amphibians, and reptiles

the renewal, regrowth or restoration of a body part

The DNA wraps around Histone like a spool and thread, when the cell prepares to divide the chromatin starters to condense and forms a chromosome

MEIOSIS : during prophase the chromosomes coil up and find their homologous pairs which then proceed to cross over, gamete (sex cells) are dividing, each new cell gets ½ of the genetic information, cells divide twice and replicate once, haploids, more steps (prophase 2, metaphase 2, anaphase 2, telophase 2, cytokinesis)

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MITOSIS : somatic (body cells) are dividing, creates exact copies of the cell, cells divide once and replicate once, Diploids

Traits need to be located on the genes in sperm and eggs in order to be passed down to offsprings.

Each individual has two allele for a gene, the alleles of each gene segregate during meiosis

When genes separate and are places within the gametes distribution is random, cannot predict with 100% accuracy

Gametes, or sex cells, go through meiosis and Stomatic, or body cells, go through mitosis

In interphase 1 the sex cells live out their normal lives and replicate their DNA. In prophase 1 the chromatin condense into chromosomes and the homologous chromosomes attach with each other and switch part of their DNA in a process called CROSSING OVER. In metaphase one the homologous sets of chromosomes line up on the metaphase plate (the sets not individual chromosomes) and spindle fibers appear.

Haploid cells are gametes and diploid cells are stomatic

Female meiosis produces the female gametes or the ova (eggs) and male meiosis produces the male gametes or sperm. In male meiosis both stages of meiosis are completed and you end up with 4 sperm cells, male meiosis also happens basically their entire life after puberty. In female meiosis, after both stages of meiosis are completed there is only 1 ovum (egg) all the nutrients are passed to that one egg and the other cells are called POLAR BODIES which will eventually disintegrate. Female meiosis only occurs in the embryonic stages of women, once females are born they have all the eggs they will have for the rest of their life.

CROSSING OVER during prophase 1 in meiosis, mutations, and environmental stimuli are all responsible for genetic variation

All gametes from an individual aren’t the same because of the law of independent assortment which states that when genes seperarate and are placed within the gametes distribution is random. In other words, gametes contain only half of the genetic makeup of a person and that certain half is different in every gamete.

During anaphase 1 the homologous chromosome sets split. During anaphase 2 the chromatid split apart at the centromere.

long fibers and histones of DNA that eventually form chromosomes

the condensed chromatin (DNA) that goes through meiosis and mitosis and is visible through a microscope

the same chromosomes from each of your parents that pair up, pair based on their size, shapes, and whats on that trait (hair color, skin pigment), have copies of the same genes, autosomes

the identical copies (chromatids) formed by the DNA replication of a chromosome which are attached by the centromere

sex cells, sperm in men, eggs in female, they use meiosis

2n (n=number of sets), cells that have 2 complete homologous chromosomes of each set, EX: human diploid number is 46, occurs in stomatic cells

1n (n=number of sets), cells that have 1 chromosome for each set, EX: humans haploid number is 23, occurs in gametes (sperm and egg)

Chromosomes are condensed versions of DNA in an organism. Genes are sections of DNA that provide instructions for a character (hitch hiker’s thumb). Alleles are different forms of a gene (H = straight thumb h = hitch hickers thumb)

Gregor Mendel fathered genetics, published an experiment in 1865 which experimented with pea plants and was focused on genetics and traits.

Parental cross refers to the first set of parents crossed. The parents' genotype would be used as the basis for predicting the genotype of their offspring (F1 generation)

1. F1

genotype - 1:2:1

phenotype - 3:1

2. F2

genotype - 1:2:1

phenotype - 3:1

Punnett squares help us to predict the variations and probabilities that can come from cross breeding.

genotype - HD : HE : HR

phenotype - D : R

D/D : D/R : R/D : R/R

9 : 3 : 3 : 1

The trait that has a higher probability of occurring and more likely to been seen (capital letter)

The trait that has a lower probability of occurring and less likely to be seen (lowercase letter)

alike genetic pairs also called purebred (EX : TT or tt)

one of each allele version (EX : Tt)

a section of DNA that provides instructions for a character (EX : hitchhiker's thumb)

different forms of a gene (EX : H=straight thumb h=hitchhikers thumb)

there are always 2 alleles, two copies of each homologous chromosomes, each carry one allele

the location of the gene on a chromosome

the transfer of genetic characters from parents to offsprings by the process of fertilization (EX : two blue eyed parents will always give birth to a blue eyed baby)

all possible allele combinations of the offspring produced (EX: heterozygous)

physical characteristics of each genotype (EX: can roll your tongue)

An individual who carries one harmful allele for an autosomal recessive disorder is known as a carrier. Carriers are heterozygous because they have two alleles of a gene.

When writing genotypes for an X linked trait you put the dominant/recessive allele on the X chromosomes (EX: XBXB or XbY)

No, since males only have one x chromosome they can only have the recessive trait or have the dominant trait, they cannot be carriers.

X-linked traits are more common in men because for men to possess this recessive trait they would need to inherit one recessive trait from their mother so she would either have to have that trait or be a carrier. But in order for a female to possess that recessive trait she would have to inherit one recessive trait from both her mother and father meaning her father would have to have that trait and her mother out also have to have it or carry it.

Description - traits that have more than 2 allele versions, if both alleles are dominant, individual shows both traits, if individual has 1 dominant and 1 recessive the dominant will mask

What does the heterozygote look like? - the heterozygote will show the dominant trait (unless it is a mix between two different dominant trains, then both traits would be shown)

How do you write the genotype - In the case of blood type you would write the genotypes like this IA IB i

Description - Allele versions do not mask each other so heterozygotes appear to be a mix of the 2 alleles

What does the heterozygote look like? - the heterozygote will appear to be a mix of the two alleles

How do you write the genotype - you would write the genotype as either a normal dominant trait or a dominant trait with a prime symbol (EX: F or F’)

With the inheritance pattern of multiple alleles offsprings are able to have traits that neither of their parents possess. They are also able to show multiple traits at once instead of those traits mixing or one masking the other.

a circumstance where the expression of one gene is modified (e.g., masked, inhibited or suppressed) by the expression of one or more other genes. ( An example of epistasis is the interaction between hair color and baldness. A gene for total baldness would be epistatic to one for blond hair or red hair)

AB - IAIB

B - IBIB IBi

O - ii

A - IAIA IAi

Blood types can either have A protein, B protein, or no protein. They can either have type O blood, type A or B blood, or type AB blood (codominance)

No, traits can also be determined by environmental factors

Males give an X to their daughters and a Y to their son.

The father determines the biological sex of the child

Shaded individuals have the trait that the pedigree is talking about.

XBXb

X-linked inheritance

You assume it's an x-linked trait

You assume it's an autosomal trait

Autosomal recessive inheritance pattern is assumed

If you determine it to be autosomal dominant you will fill in all of the unshaded shapes with the recessive genotype. If you determine it to be autosomal recessive you will fill in all of the shaded shapes as the recessive genotype.

When looking at a karyotype you can tell if there are any chromosomal abnormalities. Seeing if you have too many or not enough chromosomes can cause serious health issues

Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division

Nondisjunction can create trisomy genetic disorders like  Down's syndrome (trisomy of chromosome 21), Patau's Syndrome (trisomy of chromosome 13), Edward's Syndrome (trisomy of chromosome 18) and Turner's Syndrome (the presence of only one X chromosome)

Klinefelter's syndrome occurs when a male has an extra x chromosome, this male may be sterile, have some breast development, and have mild intellectual disabilities. Turner’s syndrome occurs when a male has no Y chromosome he just has an X, this male may be under 5 feet tall, have a webbed neck, a broad “shield like” chest, may be sterile, and may show mild intellectual disabilities.

The human diploid number is 46

all chromosomes that determine traits and characteristics, 44 autosomes (pairs 1-22)

chromosomes that determine the sex of offspring, 2 sex chromosomes (pair 23)

an individual's complete set of chromosomes.

interphase, prophase 1, metaphase 1, anaphase 1, telophase 1, cytokinesis, prophase 2, metaphase 2, anaphase 2, telophase 2, cytokinesis

the study of heredity

species traits (where you head and organs are) and individual traits (hair and eye color)

number of favorable chances / number of total possibilities

EX: 1/52 chance you will pull a 5 of hearts out of a deck of cards

a family tree that allows someone to track a trait through generations

a blank square means male and a filled in square means a male that has the trait

a blank circle means female and a filled in circle means a female that has the trait

make sure pedigree is supposed to be x-linked (either says or has more males with the trait than females)

1. label all individuals xx or xy

2. label all males X’s

3. label the first X on females (unless recessive)

4. look up/down generations to label 2nd X on females

make sure pedigree is supposed to be autosomal (same about of females and males have the trait or it says it is autosomal

1. trait D/R

2. non shaded (recessive)

3. label 1st allele

4. look up and down to label 2nd allele