Class notes Biology

$8.69

Preview 2 out of 5 pages

Class notes

Class notes Biology

0.0

(0 reviews)

- sold

5 pages

2024/2025

Institution Freshman / 9th Grade

Course Biology

Preview 2 out of 5 pages

In biology, the study of DNA, cells, mitosis, and meiosis is fundamental to understanding the building blocks of life. DNA, or deoxyribonucleic acid, is a molecule that carries the genetic instructions for the development, functioning, growth, and reproduction of all known organisms. It is composed of two strands that coil around each other to form a double helix structure. DNA contains the genetic information that is passed from one generation to the next, and it plays a crucial role in determining an organism's traits. Cells are the basic structural and functional units of all living organisms. They can be classified into two main types: prokaryotic cells, which lack a nucleus and membrane-bound organelles, and eukaryotic cells, which have a distinct nucleus and membrane-bound organelles. Cells carry out various functions such as metabolism, growth, and reproduction, and they are capable of responding to stimuli from the environment. Mitosis is a process of cell division that results in two daughter cells with the same number of chromosomes as the parent cell. It is essential for growth, development, and tissue repair in multicellular organisms. During mitosis, the genetic material is duplicated and then segregated into two identical sets, ensuring that each daughter cell receives a complete set of chromosomes. Meiosis, on the other hand, is a type of cell division that occurs in sexually reproducing organisms. It involves two successive divisions that result in the production of four daughter cells, each with half the number of chromosomes as the parent cell. Meiosis is essential for the formation of gametes (sperm and egg cells) and contributes to genetic diversity through the process of genetic recombination. Understanding the intricacies of DNA, cells, mitosis, and meiosis is crucial for comprehending the mechanisms underlying life processes and inheritance. It provides insights into the diversity of life forms and the underlying principles that govern biological systems.

Content preview

‭Science‬‭Exam‬‭review‬
‭DNA‬
-‭ ‬‭Carbon,‬‭Nitrogen,‬‭Phosphorus,‬‭Oxygen,‬‭and‬‭Hydrogen‬
‭-A‬‭double‬‭helix‬‭formed‬‭from‬‭two‬‭complementary‬‭strands‬‭of‬‭nucleotides‬‭held‬‭together‬‭by‬‭hydrogen‬‭bonds‬
‭between‬‭g-c‬‭and‬‭A-t‬‭base‬‭pairs.‬‭Duplication‬‭of‬‭genetic‬‭information‬‭occurs‬‭by‬‭using‬‭one‬‭DNA‬‭strand‬‭as‬‭a‬
‭template‬‭for‬‭forming‬‭a‬‭complementary‬‭strand.‬
‭-Deoxyribonucleic‬‭acid=‬‭DNA‬
‭-Adenine‬‭(A),‬‭Thymine‬‭(T),‬‭Guanine‬‭(G),‬‭and‬‭Cytosine‬‭©‬
‭-Nucleotide‬‭parts=‬‭A‬‭sugar,‬‭and‬‭nitrogenous‬‭base,‬‭And‬‭a‬‭phosphate‬‭group‬
‭Phosphate‬‭group:‬‭The‬‭phosphate‬‭group‬‭is‬‭a‬‭molecule‬‭that‬‭consists‬‭of‬‭one‬‭phosphorus‬‭atom‬‭bonded‬‭to‬‭four‬
‭oxygen‬‭atoms.‬‭It‬‭plays‬‭a‬‭crucial‬‭role‬‭in‬‭various‬‭biological‬‭processes,‬‭particularly‬‭in‬‭the‬‭structure‬‭and‬
‭function‬‭of‬‭nucleic‬‭acids‬‭(DNA‬‭and‬‭RNA)‬‭and‬‭in‬‭cellular‬‭energy‬‭transfer‬‭through‬‭molecules‬‭like‬‭ATP‬
‭(adenosine‬‭triphosphate).‬
‭-DNA‬‭contains‬‭the‬‭instructions‬‭needed‬‭for‬‭an‬‭organism‬‭to‬‭develop,‬‭survive,‬ ‭and‬‭reproduce‬
‭-They‬‭have‬‭DNA‬‭as‬‭their‬‭genetic‬‭material=‬‭plants,‬‭animals,‬‭bacteria,‬‭and‬‭fungi‬
‭-The‬‭DNA‬‭in‬‭prokaryotes‬‭is‬‭contained‬‭in‬‭a‬‭central‬‭area‬‭of‬‭the‬‭cell‬‭called‬‭the‬‭nucleoid,‬‭which‬‭is‬‭not‬
‭surrounded‬‭by‬‭a‬‭nuclear‬‭membrane.‬
‭-‬‭for‬‭the‬‭eukaryote‬‭cells,‬‭it‬‭is‬‭the‬‭nucleus‬
‭-The‬‭four‬‭bases‬‭that‬‭make‬‭up‬‭the‬‭rungs‬‭of‬‭the‬‭DNA‬‭ladder‬‭are‬‭Adenine‬‭(A),‬‭Thymine‬‭(T),‬‭Guanine‬‭(G),‬‭and‬
‭Cytosine‬‭(C).‬
‭It‬‭is‬‭important‬‭that‬‭weak‬‭hydrogen‬‭bonds‬‭hold‬‭the‬‭strands‬‭together‬‭in‬‭the‬‭DNA‬‭double‬‭helix‬‭because‬‭these‬
‭weak‬‭bonds‬‭allow‬‭the‬‭DNA‬‭to‬‭unzip‬‭and‬‭replicate‬‭easily‬‭during‬‭processes‬‭such‬‭as‬‭DNA‬‭replication‬‭and‬
‭protein‬‭synthesis.‬‭If‬‭the‬‭bonds‬‭were‬‭too‬‭strong,‬‭it‬‭would‬‭be‬‭difficult‬‭for‬‭the‬‭DNA‬‭to‬‭separate‬‭and‬‭carry‬
‭out‬‭these‬‭essential‬‭biological‬‭processes.‬
‭-Three‬‭scientists‬‭who‬‭significantly‬‭contributed‬‭to‬‭the‬‭discovery‬‭of‬‭the‬‭structure‬‭of‬‭DNA‬‭are‬‭James‬
‭Watson,‬‭Francis‬‭Crick,‬‭and‬‭Rosalind‬‭Franklin.‬
‭-‬‭James‬‭Watson‬‭and‬‭Francis‬‭Crick‬‭are‬‭credited‬‭with‬‭discovering‬‭the‬‭double‬‭helix‬‭structure‬‭of‬‭DNA‬‭in‬
‭1953.‬‭Their‬ ‭model‬‭revealed‬‭that‬‭DNA‬‭is‬‭made‬‭up‬‭of‬‭two‬‭strands‬‭that‬‭twist‬‭around‬‭each‬‭other‬‭in‬‭a‬‭spiral,‬
‭forming‬‭a‬‭double‬‭helix.‬

, -‭ ‬‭Rosalind‬‭Franklin,‬‭a‬‭biophysicist,‬‭made‬‭critical‬‭contributions‬‭to‬‭the‬‭understanding‬‭of‬‭DNA's‬
‭structure‬‭through‬ ‭her‬‭X-ray‬‭diffraction‬‭images‬‭of‬‭DNA,‬‭which‬‭provided‬‭key‬‭insights‬‭into‬‭the‬‭helical‬
‭structure‬‭of‬‭DNA‬‭strands.‬
‭-DNA:‬‭Deoxyribonucleic‬‭acid,‬‭a‬‭molecule‬‭that‬‭carries‬‭the‬‭genetic‬‭instructions‬‭used‬‭in‬‭the‬‭growth,‬
‭development,‬‭functioning,‬‭and‬‭reproduction‬‭of‬‭all‬‭known‬‭living‬‭organisms‬‭and‬‭many‬‭viruses.‬

D‭ ouble‬‭helix:‬‭The‬‭structure‬‭formed‬‭by‬‭double-stranded‬‭molecules‬‭of‬‭nucleic‬‭acids‬‭such‬‭as‬‭DNA.‬‭It‬‭consists‬
‭of‬‭two‬‭helical‬‭polynucleotide‬‭strands‬‭coiling‬‭around‬‭a‬‭common‬‭axis.‬

N‭ ucleotide:‬‭The‬‭basic‬‭building‬‭block‬‭of‬‭nucleic‬‭acids‬‭such‬‭as‬‭DNA.‬‭It‬‭consists‬‭of‬‭a‬‭phosphate‬‭group,‬‭a‬
‭five-carbon‬‭sugar‬‭(deoxyribose‬‭in‬‭DNA),‬‭and‬‭a‬‭nitrogenous‬‭base.‬

P‭ hosphate:‬‭A‬‭molecule‬‭that‬‭consists‬‭of‬‭one‬‭phosphorus‬‭atom‬‭bonded‬‭to‬‭four‬‭oxygen‬‭atoms.‬‭It‬‭plays‬‭a‬
‭crucial‬‭role‬‭in‬‭various‬‭biological‬‭processes,‬‭particularly‬‭in‬‭the‬‭structure‬‭and‬‭function‬‭of‬‭nucleic‬‭acids‬
‭and‬‭in‬‭cellular‬‭energy‬‭transfer.‬

‭5-carbon‬‭sugar:‬‭The‬‭sugar‬‭component‬‭of‬‭a‬‭nucleotide,‬‭which‬‭in‬‭the‬‭case‬‭of‬‭DNA‬‭is‬‭deoxyribose.‬

N‭ itrogenous‬‭base:‬‭A‬‭nitrogen-containing‬‭molecule‬‭that‬‭has‬‭the‬‭same‬‭chemical‬‭properties‬‭as‬‭a‬‭base.‬‭In‬
‭DNA,‬‭the‬‭nitrogenous‬‭bases‬‭are‬‭adenine,‬‭thymine,‬‭guanine,‬‭and‬‭cytosine.‬

G‭ enetic‬‭material:‬‭The‬‭material‬‭of‬‭which‬‭the‬‭genes‬‭are‬‭composed.‬‭In‬‭living‬‭organisms,‬‭genetic‬‭material‬
‭is‬‭usually‬‭DNA,‬‭but‬‭in‬‭some‬‭viruses‬‭it‬‭is‬‭RNA.‬

C‭ hromatin:‬‭The‬‭material‬‭of‬‭which‬‭the‬‭chromosomes‬‭of‬‭organisms‬‭are‬‭composed.‬‭It‬‭consists‬‭of‬‭DNA‬‭and‬
‭associated‬‭proteins.‬

P‭ rokaryote:‬‭A‬‭type‬‭of‬‭cell‬‭that‬‭does‬‭not‬‭have‬‭a‬‭nucleus‬‭or‬‭other‬‭membrane-bound‬‭organelles.‬‭DNA‬‭in‬
‭prokaryotic‬‭cells‬‭is‬‭contained‬‭in‬‭a‬‭central‬‭area‬‭of‬‭the‬‭cell‬‭called‬‭the‬‭nucleoid.‬

E‭ ukaryote:‬‭A‬‭type‬‭of‬‭cell‬‭that‬‭has‬‭a‬‭nucleus‬‭and‬‭other‬‭membrane-bound‬‭organelles.‬‭In‬‭eukaryotic‬‭cells,‬
‭DNA‬‭is‬‭located‬‭within‬‭the‬‭nucleus.‬

Document information

School year: 1
Uploaded on: September 23, 2024
Number of pages: 5
Written in: 2024/2025
Type: Class notes
Professor(s): Dr. allen
Contains: Biology

Report Copyright Violation

$8.69

Written by students who passed

Immediately available after payment

Read online or as PDF

Why students choose Stuvia

Created by fellow students, verified by reviews

Quality you can trust: written by students who passed their tests and reviewed by others who've used these notes.

Didn't get what you expected? Choose another document

No worries! You can instantly pick a different document that better fits what you're looking for.

Pay as you like, start learning right away

No subscription, no commitments. Pay the way you're used to via credit card and download your PDF document instantly.

“Bought, downloaded, and aced it. It really can be that simple.”

Alisha Student

Frequently asked questions

Can't I just make this for free with AI?

AI tools give you vast, general information. They don't know your course, your professor, or what actually gets asked in your exam. This document was written by a fellow student who understood the nuances of exactly this course and passed it. You get focused, curated study material, not a generic starting point you still have to rework.

Is this document still relevant for my course?

Every document shows the academic year, the linked textbook, and the institution, so you can check upfront whether it matches your course. Take a look at the free preview too to see if it fits.

What if the document isn't what I hoped?

No worries! If you change your mind within 14 days of purchase and have not downloaded the document yet, you will get a refund. Your purchase is completely risk-free.

Who am I actually buying from?

Stuvia is a marketplace: you buy directly from the student who created the document. Stuvia handles payment securely and backs every purchase with the free exchange guarantee, so you never take on any risk.

Will I be stuck with a subscription?

No. You pay $8.69 once for this document and nothing more. No subscription, no auto-renewal, no fine print.

What do I get when I buy this document?

You get a PDF that is available immediately after payment. You can read the document online or download it, and it stays accessible through your profile indefinitely.

Why can I trust Stuvia?

4.6 stars on Google and Trustpilot from over 2,000 reviews. In the past 30 days 37116 documents were sold through Stuvia internationally. And we have been doing this for 16 years now. Every document also shows its rating and how many times it has been sold.

Class notes Biology

Content preview

Document information

More like this

Recently viewed by you

Why students choose Stuvia

Created by fellow students, verified by reviews

Didn't get what you expected? Choose another document

Pay as you like, start learning right away

Working on your references?

Frequently asked questions

Can't I just make this for free with AI?

Is this document still relevant for my course?

What if the document isn't what I hoped?

Who am I actually buying from?

Will I be stuck with a subscription?

What do I get when I buy this document?

Why can I trust Stuvia?

Class notes Biology

Content preview

Document information

Browse related subjects

Subjects

Recently viewed by you

Why students choose Stuvia

Created by fellow students, verified by reviews

Didn't get what you expected? Choose another document

Pay as you like, start learning right away

Working on your references?

Frequently asked questions

Can't I just make this for free with AI?

Is this document still relevant for my course?

What if the document isn't what I hoped?

Who am I actually buying from?

Will I be stuck with a subscription?

What do I get when I buy this document?

Why can I trust Stuvia?