Tree Of Life

Question 1

What are genes made up of?

Answer 1

DNA

Question 2

Define homozygous

Answer 2

Having two identical alleles of a particular gene or genes

Question 3

Define heterogenous

Answer 3

Having two different alleles of a particular gene or genes

Question 4

Define ploidy

Answer 4

The number of chromosomes in the cells of an organism.

Question 5

Two different types of ploidy

Answer 5

Diploid and haploid

Question 6

Define phenotype

Answer 6

Phenotype is an individual’s observable, physical characteristics. (Eg. height, eye color, blood type) How an individual looks, and acts can be categorized as phenotype.

Question 7

Define genotype

Answer 7

Genotype is generally known as the genetic makeup of an organism. These traits are coded into the DNA. It represents the 2 alleles inherited for a gene.

Question 8

Adenine pairs with?

Answer 8

Thymine

Question 9

What happens in transcription?

Answer 9

mRNA is synthesized when a segment of DNA that encodes for protein is copied first. The copy is mRNA

Question 10

What is the difference between mRNA and DNA?

Answer 10

mRNA is the exact copy of the DNA sequence that codes the protein. The only differences are that mRNA is single stranded and the base thymine is replaced by uracil

Question 11

What happens in translation?

Answer 11

Synthesis of proteins

Question 12

Where does the translation start?

Answer 12

Cytoplasm

Question 13

What translates the code and how?

Answer 13

Ribosomes, one small and big form an assembly. These act like a molecular machine for protein synthesis. They release a chain of amino acids

Question 14

Define genome

Answer 14

Genomes are formed by all the genetic information in the DNA(genes and parts that don’t encode for proteins). It is measured by the number of base pairs. Consist of all genetic information.

Question 15

List advantages of asexual reproduction(3)

Answer 15

Fast – No need for a mate.
Energy-efficient – No gametes required.
Produces large numbers quickly.

Question 16

List disadvantages of asexual reproduction(3)

Answer 16

No genetic variation – Can’t adapt easily.
If the environment changes, all may die.
Mutations are passed directly to offspring.

Question 17

List advantages of sexual reproduction(3)

Answer 17

Genetic variation – Adaptability to changing environments.
Better survival chances in different conditions.
Eliminates harmful mutations over generations.

Question 18

List disadvantages of sexual reproduction(3)

Answer 18

Slow process – Finding a mate takes time.
Requires more energy (gamete production, fertilization).
Few offspring compared to asexual reproduction.(3 min)

Question 19

Example of asexual reproduction

Answer 19

Sea stars: These organisms reproduce by fission.
Hydra: They reproduce by budding.
Yeast: These organisms reproduce by budding.
Paramecium: They produce offspring by binary fission.

Question 20

Define Mitosis

Answer 20

Mitosis is a process in which a cell divides into two identical daughter cells. It’s a type of cell division that occurs in eukaryotes.

Question 21

What is mitosis responsible for?

Answer 21

Mitosis is responsible for the growth and replacing worn-out cells.

Question 22

Define Meiosis

Answer 22

Meiosis is a type of cell division that produces sex cells, or gametes, like eggs and sperm. During meiosis, a single cell divides twice, creating four daughter cells with half the original amount of genetic material

Question 23

Describe prophase

Answer 23

The chromatin condenses into visible chromosomes, the nuclear membrane breaks down, and the spindle fibers begin to form.

Question 24

Describe metaphase

Answer 24

The chromosomes align at the cell’s equatorial plate, attached to spindle fibers from opposite poles.

Question 25

Describe anaphase

Answer 25

The sister chromatids separate and are pulled toward opposite poles of the cell.

Question 26

Describe telophase

Answer 26

The separated chromosomes decondense, nuclear membranes reform around each set, and the spindle fibers break down

Question 27

What do gene mutations in DNA lead to?

Answer 27

Gene mutations in DNA can lead to different amino acids being translated which in turn may change the structure and function of the entire protein.

Question 28

When can mutations happen?

Answer 28

Mutations can happen when DNA replicates during cell division, but can also be induced by other mutagens such as chemical or ionizing radiation.

Question 29

Define germline mutations

Answer 29

Germline mutations carried in the gametes are hereditary and will be passed on during sexual reproduction to the offspring.

Question 30

Define chromosome mutations

Answer 30

Chromosome mutations are caused by mistakes in the separation of chromosome tetrads during meiosis 1 by nondisjunction when sister chromatids fail to separate in meiosis 2 as in the case of Down syndrome.

Question 31

Possible advantage of mutation example

Answer 31

A mutation that causes a deletion of 32 bases in the CCR5 gene increases resistance to HIV or delays its progress to AIDS.

Question 32

Define genetic modification

Answer 32

This can be defined as changing an organism’s genotype using biotechnology tools or techniques

Question 33

Define recombinant DNA

Answer 33

DNA that has been formed artificially by combining constituents from different organisms and is used in genetic modification

Question 34

What is a transgenic organism?

Answer 34

An organism consisting of genetic material from another organism

Question 35

How does CRISPR work?

Answer 35

CRISPR is a gene editing tool that uses nuclease Cas9. Using a specific guide RNA that can be designed in the lab, Cas9 can be guided with the specific guide RNA in order to cut points around a specific target gene. This leads to more specific controlled gene editing.

Question 36

What are stem cells

Answer 36

Stem cells can make more cells like themselves and they become other cells that do different things.

Question 37

3 main types of stem cells

Answer 37

Pluripotent, Multipotent, Unipotent

Question 38

Define pluripotent stem cells

Answer 38

Pluripotent Stem Cells: These cells can become any cell type except those required for fetal development.

Question 39

Benefits of stem cells

Answer 39

People who might benefit from stem cell therapies include those with leukemia, Hodgkin disease, non-Hodgkin lymphoma and some solid tumor cancers.