Genetics

Question 0

What is fertilization?

Answer 0

The fusion of the nuclei of the male and female gametes, which forms a zygote

Question 1

What are Gametes?

Answer 1

Specialized sex cells

Usually 2 kinds “male” & “female”

Each gamete has half the number of chromosomes as the parent cell from which it came

Question 2

What is a zygote?

Answer 2

A single cell formed by fusion of gametes at fertilization

Question 3

What is a somatic cell?

Answer 3

AKA BODY CELLS!!!
All cells in the body other than those that produce gametes
Every species of organism has certain number of chromosomes in it’s somatic cells

Question 4

What are homologous chromosome?

Answer 4

A pair of similar chromosomes , similar in size, shape, and genetic content

Question 5

What are sister chromatids?

Answer 5

Exact replicas

Question 6

Another name for body cells?

Answer 6

Somatic cells!!!

Question 7

How many pairs of chromosomes does your body have?

Answer 7

23 for each homologous pair one chromosome comes from each parent

Question 8

Autosomes? And sex chromosomes?

Answer 8

Chromosome pairs 1-22

X and Y determine gender in mammals

Question 9

Body cells are?

Answer 9

Diploid!
Have 2 copies of every chromosome (2n)
Half chromosomes come from each parent
46 in humans

Question 10

Gametes are?

Answer 10

Haploid!!
Have 1 copy of every chromosome
Have 22 Autosomes and 1 sex chromosome
23 in humans

Question 11

What is major in meiosis?

Answer 11

It makes diploid cells into haploid cells

Question 12

Why is making diploid cells into haploid important? Explain why it’s important?

Answer 12

It’s important because if you don’t a person will have extra chromosomes resulting in defects

Question 13

What happens in meiosis 1?

Answer 13

Homologous chromosomes seperate

Question 14

What happens in meiosis 2?

Answer 14

Sister chromatids are separated

Question 15

What happens in Prophase 1? Why is it important?

Answer 15

Important because homologous chromosomes pair up and form tetrad

Increases variety!!

May tangle leading to !!crossing over!!- exchange of chromosomal segments

Question 16

Anaphase 1

Answer 16

Disjunction occurs— homologous pairs seperate(pulled to opposite poles)

Non disjunction– when the homologous pairs don’t seperate

Question 17

What are the advantages of sexual reproduction?

Answer 17

Variation
Parents and offspring not exactly alike
Environmental change + variation– possibility of survival of the species

Question 18

Genetics? Traits?

Answer 18

The study of biological inheritance patterns and variation

Distinguishing characteristics that are inherited

Question 19

In heterozygous individuals this is not seen?

Answer 19

Recessive allele

Question 20

What is an allele?

Answer 20

Different forms of a gene for a particular trait

Question 21

Genotype? Phenotype?

Answer 21

The genetic makeup of an organism (Tt ,tt)

The physical trait an organism develops as a result of it’s genotype (tall or short)

Question 22

Larry the lizard has long legs..Phenotype or genotype?

Answer 22

Phenotype

Question 23

Timothy the turtle is heterozygous for crazy eyes…phenotype or genotype?

Answer 23

Genotype

Question 24

In which of Mendel’s laws is 1 allele seen in phenotype and the other is hidden?

Answer 24

Law of Dominance

Question 25

A cross between 2 heterozygous individual who for 1 trait follows Mendel’s law of dominance?

Answer 25

Monohybrid cross

Question 26

This is used to find out the genotype if an individual who shows the dominant form of the trait?

Answer 26

Test cross

Question 27

Monohybrid cross ratios !! Important!!

Dihybrid cross ratio!!!

Answer 27

Genotype- 1:2:1
Phenotype- 3:1

Phenotype- 9:3:3:1

Question 28

Says that factors occur in pairs and are seperarted from each other during gamete formation?

Answer 28

Law of Segregation

Question 29

Homozygous? Heterozygous?

Answer 29

Describes an organism with 2 alleles that are the same

Describes an organism with 2 alleles that are different

Question 30

All non sex chromosomes?

Answer 30

Autosomes

Question 31

Purebred? Hybrid? Cross?

Answer 31

–Organism that receives the same form of a generic trait from both it’s parents

–Organism that recieves different forms of a genetic trait from each parent as a result of a cross between purebred parents

–When 1 organism is going to reproduce with another

Question 32

2n is equivalent to what term we already learned?

Answer 32

Diploid

Question 33

If the tree has 18 chromosomes in it’s somatic cells how many are in it’s diploid cells?

Answer 33

18

Question 34

A squirrel has 32 chromosomes in it’s somatic cells how many does it’s gametes have?

Answer 34

16

Question 35

A red tulip has 22 chromosomes in it’s gametes, what is the haploid #?

Answer 35

22

Question 36

Punnett square?

Answer 36

Grid system for predicting all possible genotypes resulting from a cross

Question 37

Whose gametes determine offspring sex?

Answer 37

Male

Question 38

Carrier?

Answer 38

Doesn’t show the phenotype, but can pass on the recessive allele to offspring

Question 39

Why do men show recessive linked diseases?

Answer 39

Women have the ability to mask the trait because they have two X chromosomes unlike men who only have 1

Question 40

Law of independent assortment?

Answer 40

Genes for different traits are separated and distributed independently of each other

Question 41

Law of large numbers?

Answer 41

Deals with probibility
No one event is more likely to happen than another, all will happen in equal #s of trials
Allows predictions on inherited traits

Question 42

Incomplete dominance

Answer 42

Both alleles contribute to phenotype of heterozygous individual to produce trait not exactly like homozygous parent

Question 43

Codominance

Answer 43

2 dominant alleles are expressed at the Same time