4.6 Regulation of the Cell Cycle
in AP Biology
Levels of proteins called cyclins increase and decrease during the cell cycle. Cyclins were discovered in studies of mitosis in sea urchin gametes.
4.5 The Cell Cycle
in AP Biology
Mitosis is just one part of the cell cycle, the life of a cell from the time it is first formed during division of a parent cell until its own division into two daughter cells
4.4 Feedback in Cell Communication
in AP Biology
Negative feedback helps to maintain homeostasis. Positive feedback is self-reinforcing and amplifies responses.
4.3 Changes in Signal Transduction Pathways
in AP Biology
Food and drugs can be sources of chemicals that act as exogenous ligands in cell communication. Exogenous ligands can disrupt the usual activity of a signal transduction pathway, thereby altering the responses of target cells.
4.2 Signal Transduction
in AP Biology
Signal Transduction pathways differ in specific details, but have certain, unifying characteristics. All pathways follow a sequence: Reception，Transduction, Response
4.1 Cell Communication
in AP Biology
Cells communicate by sending and receiving chemical messengers. Cells can communicate over various distances
青春的海 有无数种浪花
Written by Audrey, Clara, and Malina
没关系，继续奔跑吧！带着热气和疼痛的文字被笑着吞咽。不要温和地走入那个良夜，要活泼地跑到那个灼日。
Statistics in Science
in AP Biology
Dive into the essential concepts of biostatistics to bolster your exam preparation and scientific inquiry skills.
2023-25两学年原核与真核细胞
优秀作业展示：原核细胞与真核细胞
3.4 Photosynthesis
in AP Biology
The conversion process that transforms the energy of sunlight into chemical energy stored in sugars and other organic molecules is called photosynthesis. Photosynthesis nourishes almost the entire living world directly or indirectly.