Unit 4, Quiz 2 Flashcards
Cells need to reproduce or divide so that organisms can _______ and __________ damaged cells.
- Grow
- Repair
Most of a cell’s life is spent during a period of growth and development. What is this stage called?
Interphase
Directions: Is the following statement true or false?
Interphase is technically a stage of mitosis.
False. Interphase is like the preperation for mitosis. This is the period where chromosomes duplicate themselves. It’s not an active phase of cell division.
Give two examples of cells that are permanently stuck in interphase.
- Nerve cells
- Muscle cells
What is mitosis?
Mitosis is the process in which a eukaryotic cell splits into two new daughter cells, each having the same number of chromosomes as the parent cell
How many chromosomes is a healthy human supposed to have?
46
Name the six stages of mitosis in order.
- Interphase (technically not a part of mitosis)
- Prophase
- Metaphase
- Anaphase
- Telophase
- Cytokinesis
What is asexual reproduction?
The process in which one parent creates two identical offspring
Directions: After being provided the definition, name the term to the best of your ability.
When a new plant grows from a fragment or cutting off of the parent.
This is referring to simple mitosis, in the context of vegetative propagation.
What organisms use simple mitosis (vegetative propagation)?
Both potatoes and strawberries can reproduce through vegetative propagation, which involves simple mitosis.
What is binary fission?
What is an example of an organism that uses it?
- Binary fission is a method of asexual reproduction where DNA is duplicated and the cell grows bigger and splits
- Bacteria
Directions: True or False? If false, correct the statement.
Binary fission only occurs in single-celled organisms (prokaryotic).
True
What is budding?
What are examples of animals that use this?
- Budding is when the parent grows a mini-version of itself that eventually breaks off to form a new organism.
- Some organisms that use this are hydra and jelly fish.
If an organism can make new cells, tissues, or organs after injury, what is this process called?
Regeneration
Directions: True or False? If false, correct the statement.
Regeneration is a form of asexual reproduction that starfish, worms, lizards, and the human liver use.
True
What is sexual reproduction?
The process in which sex cells from 2 parents create similar offspring
Gametes are another name for what?
Sex cells
Directions: Fill in the blanks to the best of your ability.
Sperm is made by males in the _________. They are very _________, have a head, __________, and __________________.
- Testicles
- Small
- Neck
- Flagellum
Directions: Fill in the blanks to the best of your ability.
Eggs are made by ____________ in the ___________. They are relatively __________ compared to sperm, and they contain ________.
- Females
- Ovaries
- Large
- Food
How many pairs of homologous chromosomes do human body cells have?
23 pairs of homologous chromosomes, or 46 altogether
When sperm (XY) and an egg (XX) fuse together (fertilization), what new organism is created?
Zygote
Directions: True or False? If false, correct the statement.
All sperm created are XY.
False. 50 percent of sperm are XY, and the other half is XX.
If an XX sperm fuses with an egg, is a boy or girl going to be birthed?
Girl (female)
Directions: Fill in the blanks to the best of your ability.
In meiosis, a sex cell splits (or divides) _____ times, creating _______ new daughter cells, each having _________ the number of chromosomes as the parent cell.
- Two
- Four
- Half
Directions: Fill in the blanks to the best of your ability.
In females one ______ and three ______________ are made every time meiosis occurs.
- Egg
- Polar bodies
Where are chromosomes found in an organism?
Chromosomes are found in the nuclei of every cell.
Directions: True or False? If false, correct the statement.
An organism’s genes are found on the chromosomes.
True
What is a gene?
A gene is a segment of DNA; it is a set of instructions for an inherited trait
Think of it like this: DNA is like a big instruction book, and genes are individual chapters in that book.
What are the genes responsible for?
The production of proteins, and thus, all of the organism’s traits.
DNA has the shape of a spiral staircase or a “twisted” ladder. This shape is scientifically called what?
A double helix
Who discovered the shape of DNA?
Watson and Crick. They won a nobel prize for this. Earlier work was conducted by Rosalind Franklin with an X-Ray.
DNA is made up of smaller subunits called _____________.
Nucleotides
Name the three things that each nucleotide in DNA consists of.
- Phosphate
- Sugar
- Nitrogen Base
Name the four nitrogen bases in DNA.
- Adenine
- Guanine
- Cytosine
- Thymine
Directions: Fill in the blanks to the best of your ability.
The “handrails” of the double helix molecule are made from the __________ and ___________ groups. The “steps” or “rungs” of the double helix molecule are made from the ___________________.
- Sugars
- Phosphate
- Nitrogen bases
What is Chargaff’s Rule?
Chargaff’s Rule is that adenine always matches with thymine, and cytosine always matches with guanine.
Directions: True or False? If false, correct the statement.
RNA is the chemical that actually helps the ribosomes make proteins. It is made from a single strand of DNA that has “unzipped” from the double helix shape.
True
Name two main differences between RNA and DNA.
- RNA is single-stranded.
- RNA does not contain the nitrogen base thymine. Instead, uracil takes its place.
