Unit 4: Heredity and Evolution
Chapter 5: Heredity, Section 1: Genetics
1. ______________--the study of heredity
Green workbook pp. 67-72
2. _______________-- the passing of traits from one generation to the next
3. ___________-- any characteristic of an organism that parents can pass to
offspring (ex: eye color, height, hair color, etc.)
4. _______________—the new organism produced by a parent or parents
(synonyms: children, young, descendants)
5. ___________ _____________—the “Father of Genetics”
6. ___________—(deoxyribonucleic acid) determines what traits are passed
from one generation to the next; located in the nucleus
7. __________________—tightly coiled structures that contain genetic
information (made up of DNA)
8. ___________– a segment of DNA that determines a trait; found on
chromosomes
9. _____________--the different forms of a gene; different alleles produce
different results
a. Why do children tend to look like their parents in some way?
___________________________________________________________
___________________________________________________________
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b. During sexual reproduction, offspring receive chromosomes from both parents.
For each trait, the offspring inherit one allele from the mother and one allele
from the father. This gives each offspring a unique combination of genes.
10. _____________________—a trait that is always expressed in the phenotype;
if the organism has that allele, it will show the trait; represented by capital
letters
11. __________________—a trait that is only expressed when two of these
alleles are present; represented by lowercase letters
b. If an offspring receives one dominant allele and one recessive allele for a trait,
the ________________ trait is not expressed.
12. ____________________--the genes an organism carries
13. __________________--a physical trait of an organism; the way the genes are
expressed
Unit 4: Heredity and Evolution
14. ____________________________--two of the same alleles for a trait;
another way to refer to purebred organisms
15. __________________—an organism with two of the same alleles for a trait;
another way to refer to a homozygous genotype
16. ___________________________--two different alleles for a trait; another
way to refer to a hybrid organism
17. ____________—an organism with two different alleles for a trait; another
way to refer to heterozygous genotypes
18. _____________ _____________--a tool to help geneticists predict the
probability of certain traits in offspring by showing all of the ways the parents’
alleles can combine
19. _____________________--the relative possibility that an event will occur
Sexual and Asexual Reproduction
20._______ ____________—the formation of new cells from cells that have a
nucleus; they divide, then divide again
21. _____________—the process in cell division by which the cell’s nucleus divides
to form two nuclei, each with the same exact chromosome and DNA as the original
22.________________—the process where the number of chromosomes in body
cells is reduced by half in sex cells
23. _______________ reproduction—when specialized cells from two parents join
to create an offspring; genetic information is contributed from both parents
24. ________________ reproduction—reproduction that involves only one parent
therefore offspring have identical traits to their parent
25._____________ — a form of asexual reproduction in which an offspring (called
a daughter) forms from an outgrowth of a larger parent organism; ex. yeast
26.____________ ____________—a form of asexual reproduction where a
chromosome is copied before the cell divides to form two new cells; ex. bacteria
Unit 4: Heredity and Evolution
Selective Breeding
Many plants and animals have been bred to produce traits desired by humans.
List some examples: ______________________________________
27. ______________________
_____________________--the process
through which humans use naturally occurring genetic patterns to pass desired
traits on to generations of plants and animals
28. _______________________--selective breeding in order to maintain similar
characteristics in a line of organisms
29. ___________________--selective breeding that involves crossing individuals
with different traits to obtain organisms with the best traits of each parent
30. ______________ ______________________--the process of removing a
bit of genetic material from one organism and inserting it into another
31. ______________ --the process of using the genetic information from a single
cell of an organism to produce another organism with the same genetic information
32. __________________--the rules of conduct recognized in respect to a
particular class of human actions or a particular group, culture, etc.
What is alright to do and what should never be done?
Unit 4: Heredity and Evolution
Meiosis
• Sexual Reproduction requires ____ two parents to produce offspring.
______ organisms reproduce sexually. This requires a sex cell from each
parent.
•
The sex cell produced by ________ is sperm. The sex cell produced by
____________ is an egg. Another word for sex cell is gamete.
What are chromosomes?
• They are found in the ____________ of cells and are made of ______.
They determine all of the physical characteristics (phenotypes) of
organisms. Alleles, or ________, are on the chromosomes.
•
Different organisms have different numbers of chromosomes. Humans have
____ pairs for a total of 46.
Sutton & Grasshoppers
• Walter Sutton used a ___________ to count the chromosomes in
grasshopper cells. He counted ____ chromosomes in every cell, except the
sex cells. Those cells only had ___ chromosomes.
What did Sutton learn?
• He figured out that grasshoppers must get _____ of their chromosomes
(and alleles) from the ________ parent and ______ from the male parent.
12 chromosomes in the egg
+ 12 chromosomes in the sperm
24 chromosomes in the zygote (fertilized egg)
What is meiosis?
• The process where the number of chromosomes in body cells is reduced by
half in _____ cells. This happens through a series of_________ .
•
You may have your mother’s _______ and your father’s _____ because of
the _________ you received from each parent through your father’s sperm
and your mother’s egg.
Asexual Reproduction
• Asexual ______________ is where offspring are produced by only _____
parent. Since offspring receive ______ of their genes from that one
parent, they are _______________ to that parent.
Unit 3 Vocabulary