Quiz 1

Question 0

Heredity

Answer 0

The passing of traits from parents to offspring

Question 1

Genetics

Answer 1

The scientific study of heredity and variation

Question 2

Gene

Answer 2

A segment of DNA which codes for a particular trait

Question 3

Locus

Answer 3

The location of a gene on a chromosome

Question 4

What does the structure of a chromosome look like?

Answer 4

[refer to diagram in notes]

Question 5

Sister chromatids

Answer 5

The double sets of chromosomes attached at the centromere

Question 6

Centrioles

Answer 6

An organelle that produces spinal fibres. Also called centrosomes

Question 7

Diploid

Answer 7

Cells have 2 sets of chromosomes (2n)

Question 8

Haploid

Answer 8

Cells have 1/2 the normal sets of chromosomes

Question 9

Polypoid

Answer 9

Cells have 3 or more sets of chromosomes

Question 10

Chromosome

Answer 10

Found in the nucleus of eukaryotic cells. Made up of DNA. They occur in sets

Question 11

How many chromosomes do humans have?

Answer 11

46

Question 12

Interphase

Answer 12

The longest phase of the cell in which the cells perform all normal life functions, the cell grows in size, and the organelles and DNA are duplicated

Question 13

Mitosis. What does it ensure?

Answer 13

The middle section of the cell cycle in which 2 identical diploid daughter cells are produced. It ensures each new cell has a nucleus with chromatin

Question 14

Prophase

Answer 14

The DNA condenses and thickens to form chromosomes (coiled DNA) and the nuclear membrane starts to dissolve. Centrioles migrate to poles of cell and spindle fibres attach to centromere

Question 15

Metaphase

Answer 15

Nuclear membrane completely dissolves and chromosomes line up along the middle of the cell

Question 16

Anaphase

Answer 16

Each chromosome separates into two identical single-stranded parts (formally the chromosomes now sister chromatids). Sister chromatids are pulled toward end of each cell, because spindle fibers contract

Question 17

Telophase

Answer 17

Single stranded chromosomes coil into thin strands of chromatin. Spindle fibers dissolve, and the nuclear membrane reforms

Question 18

Cytokinesis

Answer 18

Cytoplasm and organelles separate. Two daughter cells form. In animal cells, cell pinches into two. In plant cells, a cell wall forms, dividing it into two parts

Question 19

DNA

Answer 19

Deoxyribonucleic acid: a molecule that carries genetic information for cells, it makes up a chromosome

Question 20

Chromatin

Answer 20

The genetic material which is made up of DNA strands

Question 21

What is a gamete? What do they include? How are they produced?

Answer 21

They are haploid sex cells. They include egg and sperm cells. Produced by meiosis

Question 22

What is fertilization? What is the product?

Answer 22

The joining/fusion of two gametes. The new cell produced is diploid, called a zygote.

Question 23

Homologous chromosomes

Answer 23

Matching pairs of chromosomes. Each chromosome of the pair is composed of a pair of sister chromatids (the structure is a tetrad)

Question 24

Meiosis? What are the 2 stages?

Answer 24

A two-stage cell division in which the resulting daughter cells have half the number of chromosomes as the parent cell. It produces four haploid gametes cells

Question 25

Prophase 1

Answer 25

Chromosomes shorten and thicken. Nuclear membrane starts to dissolve. Sister chromatids come together as homologous pairs (this structures called a tetrad). Synapsis then occurs, causing crossing over

Question 26

Metaphase 1

Answer 26

The tetrads migrate towards the center of the cell

Question 27

Anaphase 1

Answer 27

Homologous chromosomes are pulled by spindle fibres and move to opposite poles. Reduction division occurs cutting number of chromosomes in half

Question 28

Telophase 1

Answer 28

Nuclear membrane starts to reform and cell begins to divide. The new cells are haploid

Question 29

Prophase 2

Answer 29

Nuclear membrane reforms and spindle fibres begin to reform

Question 30

Metaphase 2

Answer 30

Sister chromatids line up NEXT to each other across the equator of cell

Question 31

Anaphase 2

Answer 31

Sister chromatids software and move to opposite poles. Nuclear membrane starts to form around chromatids, now called chromosomes

Question 32

Telophase 2 and cytokinesis

Answer 32

Cytoplasm and organelles divide. 4 haploid non-identical daughter cells (gametes) are produced.

Question 33

Tetrad

Answer 33

The structure of homologous pairs

Question 34

Synapsis and crossing over

Answer 34

Each sister chromatid intertwines with a sister chromatids from its matching homologous chromosome. The intertwined chromatids from different chromosomes break and reattach to each other, exchanging DNA

Question 35

Reduction division

Answer 35

When only 1 of the sister chromatids from each homologous pair are found in each new daughter cell. (Cutting number of chromosomes in half)

Question 36

Gametogenesis

Answer 36

The process where gametes are produced. Occurs in reproductive organs (plants: flowers, humans: gonads). Cells produced are haploid

Question 37

Oogenesis

Answer 37

The process where mature eggs are produced in the ovaries. [refer to notes for diagram]

Question 38

Spermatogenesis

Answer 38

The production of sperm cells in the testes. [refer to notes for diagram]

Question 39

Random assortment

Answer 39

In metaphase 1 the chromosomes arrange into homologous pairs (across the cell's equator) and depending on how they line up, a number of different combinations may be found in the gametes

Question 40

How can we calculate the need of chromosome combinations for any diploid (2n) organism?

Answer 40

We can't use 2^n, where n is the number of pairs

Question 41

Largo types

Answer 41

A photograph of all the chromosomes of an individual. Useful for determine gender, diagnosing chromosome abnormalities which lead to health issues

Question 42

What are chromosome abnormalities? What are the 2 kinds of errors?

Answer 42

Abnormalities that occur with chromosomes during meiosis. Type 1) changes in chromosomal structure. Type 2) changes in chromosomal number

Question 43

Chromosomal structure changes

Answer 43

During crossing over, the chemical bonds that hold DNA together in the chromosome are broken, then reformed. Sometimes they don't reform correctly! Also, sometimes non-homologous pairs cross over, producing chromosomes with genes not normally found in that chromosome.

Question 44

What are the 4 types of errors in chromosomal structure changes?

Answer 44

A) deletion - a chromosome is missing a piece of DNA B) duplication - a chromosome has an extra piece of DNA C) inversion - the piece of DNA gets flipped upside down D) translocation - a chromosome shares a piece of DNA with a non-homologous pair

Question 45

Changes in chromosomal number. What is non-disjunction?

Answer 45

Sometimes homologous pairs of sister chromatids don't separate properly. This is called non-disjunction and can occur in anaphase 1 or 2

Question 46

What are the 2 kinds of errors of changes in chromosomal number?

Answer 46

A) monosomy: missing 1 chromosome. Kurds when a single chromosome is in place of a homologous pair. Ex) in turned syndrome there is 1 X chromosome missing B) trisomy: 1 extra chromosome. Occurs when there are 3 chromosomes in place of 1 homologous pair. Ex) in Down syndrome there is an extra chromosome #21

Question 47

What are the 4 non-disjunction disorders?

Answer 47

``` Patau syndrome Turner syndrome Klinefelter syndrome Down syndrome Edwards syndrome ```

Question 48

Patau syndrome

Answer 48

Chromosome #13 has 3 copies of genetic material. Causes cleft lip, extra fingers and toes

Question 49

Klinefelter syndrome

Answer 49

Results in an extra copy of the X chromosome in each cell. Interferes with male sexual development and age delay for learning to walk

Question 50

Turner syndrome

Answer 50

The deletion of the second X chromosome. Causes short stature, puffy hands and feet, curvature of spine, overweight, lazy eye, etc.

Question 51

Down syndrome

Answer 51

When you have an extra chromosome #21. Causes extra space between big toe and 2nd toe, and hyper-flexibility

Question 52

Edwards syndrome

Answer 52

Extra copy of chromosome #18. Causes mental delay and smaller head

Question 53

Recombinant DNA

Answer 53

Taking one chromosome and putting it into a completely different cell. (From one species to another). Ex) GMO: genetically modified organism. Like strawberries

Question 54

Artificial insemination

Answer 54

Inserting sperm cells into the uterus of am the female organism to fertilize an egg. Used commonly in animal breeding and livestock

Question 55

In vitro fertilization

Answer 55

"Test-tube baby". Manually combing sperm and egg in a lab dish and transferring the embryo to the uterus. Ex) dairy cows

Question 56

Cloning

Answer 56

Removing a mature somatic cell (such as a skin cell) from an animal they want to copy. Then they transfer the DNA of the donor into the egg cell (which has had its own nucleus containing DNA removed). Ex) people clone animals so farmers can raise them for human organ transplants