5.4 Inheritance

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 3

1. How many chromosomes can we find in a muscle cell of a cat? 
2. How many chromosomes can we find in the sperm cell of a zebra?
   
3. How many chromosomes can we find in the pollen cell of corn / maize?
   
4. How many chromosomes does a baby gorilla receive from its mother? And how many from its father?
   
5. Do brain and skin cells of dogs have the same amount of chromosomes in their nuclei?
   
6. Do all species have their own amount of chromosomes?

USE THE TABLE!

The building blocks for proteins are called ...

1. DNA
2. RNA
3. Amino acids
4. Ribosomes

A segment of DNA that codes for one protein is called a ...

The molecule
shown in the
picture is called ...

1. DNA
2. RNA
3. an amino acid
4. a ribosome

The structure
shown in the picture is called a...

A segment of DNA has the following order of nucleotides : ATTGGCAGTA. What is the order of nucleotides on the other strand?

5.4 INHERITANCE

• You describe, explain, recognize and apply the following terms; homozygous, heterozygous, gene, alleles, dominant, recessive, carrier, P-generation, F1-generation, F2-generation.   
• You can use your knowledge about inheritance and a Punnet-square to predict the probabilities of offspring having a given genotype or phenotype.
  
• You can explain that you have two alleles for each gene.
  
• You can use and recognize the notation for homozygous dominant (AA) /recessive (aa) and heterozygous genotypes (Aa).  

VWO: 

• You can recognize, describe and apply in a context what incomplete dominance is.  

Allele =

Alleles =

NOTE.

 • Dominant allele = 

 • Recessive allele = 

Oliver says: 'all humans have the same genes, but not the same alleles'. Charley says: 'all humans have the same alleles, but not the same genes'. Who is right?

1. Oliver
2. Charley
3. They both are
4. They are both wrong

Is it a gene or an allele?

GENE

ALLELE

skin colour

curly hair

flower colour

blue eyes

blood type

type A blood

colour-blindness

hair type

short wings in a fruit fly

NOTE. INHERITANCE (terminology)

Heterozygous = 

Homozygous=

Homozygous dominant=

Homozygous recessive=

HOMEWORK

Exercises on 5.4

Some fruit flies have curly wings instead of normal wings (see the pictures below). Answer the questions using the letter R for normal wings and r for curly wings:

normal wings                 curly wings

a. Which is the dominant allele? Give the letter and the characteristic.

b. Which is the recessive allele? Give the letter and the characteristic.

c. What is the genotype of a fruit fly that is homozygous for curly wings? 

d. Which two genotypes will result in the ‘normal wings’ phenotype?

e. Can a fruit fly with curly wings have a heterozygous genotype? Explain your thinking.

CALCULATE THE CHANCE. 

Check out the steps on page 136.  

Let's practice! A guinea pig is heterozygous and has blue fur. This guinea pig mates with a guinea pig with yellow fur. Use a punnet square to determine the probability of one of their offspring having blue fur.

LET'S PRACTISE!

Download the exercises on Teams. 

Do the exercises to practise & apply the learning goals.