Lecture--Chapter 1 Flashcards Preview

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Flashcards in Lecture--Chapter 1 Deck (45):
1

Genes are:

unit of heredity

2

Traits are:

characteristics

3

Genomes are:

all the DNA contained within the chromosomes

4

Approximately how many genes code for proteins that perform most life functions?

20 000 - 25 000

5

Approximately how many DNA base pairs per set of chromosomes?

3 billion

6

The four major groups of cellular macromolecules are:

1. lipids
2. carbohydrates
3. proteins
4. nucleic acids

7

What are lipids?

Molecules that form fats, phospholipids, waxes, steroids; function in energy metabolism and components of membranes.

8

What are carbohydrates?

Molecules composed of hydrocarbon-rings, which form monosaccharides and polysaccharides; function in energy metabolism and storage polymer formation.

9

What is an example of a monosaccharide?

glucose

10

What is an example of a polysaccharide?

starch

11

What are proteins?

polymers of amino acids (polypeptides); function in cell structures, immune defense, as enzymes; proteome

12

What is a proteome?

All of the proteins that an organism can make.

13

What are nucleic acids?

DNA or RNA; polymers of nucleotides; hereditary information, direct protein synthesis.

14

Each nucleotide of DNA contains one:

nitrogenous base

15

What are the nitrogenous bases?

1. adenine
2. thymine
3. cytosine
4. guanine

16

What is a nucleotide?

a molecule containing a sugar, a phosphate, and a nitrogenous base

17

What is a triplet code?

genetic information stored in the linear sequence of bases

18

Start codon:

ATG (codes for methionine)

19

What are the three different traits?

1. morphological traits
2. physiological traits
3. behavioural traits

20

morphological traits:

affect the appearance, form, and/or structure of an organism

21

physiological traits:

affect how an organism functions

22

behavioural traits:

affect the ways an organism responds to the environment

23

Traits are affected by:

the gene allele that is expressed

24

Traits are expressed:

at different levels of biological organisation

25

Traits are governed:

both by genes and by the environment

26

What is a morph?

A contrasting form within a single species (2 or more phenotypes of the same species that occupy the same habitat at the same time, within a population with random mating).

27

Genetic variation is a result of different types of changes at the DNA molecular level:

1. gene mutations
2. chromosomal mutations
3. aneuploidy

28

What are gene mutations?

any change in the local DNA sequence as simple as a single nucleotide change; create new alleles

29

What are chromosomal mutations?

any change in the structure of the chromosome; deletions, inversion, translocations, or duplications

30

What is aneuploidy?

chromosomes lost or gained

31

Define biological evolution:

The genetic makeup of a population can change over many generations.

32

Define natural selection:

The gradual, non-random process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers; beneficial alleles have a higher probability of being passed onto subsequent generations.

33

Random DNA mutations lead to:

1. neutral alleles
2. beneficial alleles
3. deleterious alleles

34

Neutral alleles:

no advantage or disadvantage to the individual

35

Beneficial alleles:

are advantageous to individuals since they make them better able to compete for resources and reproduce

36

Deleterious alleles:

make individuals less able to compete for resources and reproduce

37

What are the 2 different experimental approaches that genetics research uses?

1. hypothesis testing
2. discovery-based science

38

What are the three fields of genetics research?

1. transmission genetics
2. molecular genetics
3. population genetics

39

Transmission genetics:

examines how traits are passed from one generation to the next

40

Molecular genetics:

deals with the molecular features of DNA and how these underlie gene expression

41

Population genetics:

deals with the genetic composition of populations and how it changes over time and space

42

What does transmission genetics entail?

1. looks at patterns of inheritance (Mendelian and non-Mendelian)
2. the basic experimental approach in transmission genetics is the genetic cross

43

What is the genetic cross?

the mating of 2 individuals and analysis of the traits of their offspring over several generations

44

What does molecular genetics entail?

1. goal is to describe the molecular features of gene structure and function, scaling from DNA molecules to whole genomes
2. molecular technologies allow the introduction of genes into animals and plants--treatment for genetic diseases; agriculture modification of animals and plants in various ways

45

What does population genetics entail?

1. connects the work of Mendel on inheritance to that of Darwin
2. genetic technologies allow the introduction of genes into animals and plants--agriculture modification of plants and animals; gene therapy for treatment of genetic diseases