Answer:
One in 14 middle school students has used cigarettes in the past 30 days and one in 4 high school students has used cigarettes in the past 30 days.
Explanation:
Source: CDC 2018
Answer:
OBJECTIVES:
To observe symptoms and signs of representative diseases caused by the Oomycete pathogens.
To become familiar with vegetative and reproductive structures of the Oomycetes, and their role in disease development.
INTRODUCTION:
The Oomycetes, also known as water molds, are a large group of terrestrial and aquatic eukaryotic organisms. Although they superficially resemble fungi in mycelial growth and mode of nutrition, molecular studies and distinct morphological characteristics place them in the kingdom Chromalveolata (phylum Heterokontophyta, the 'stramenopiles') with brown and golden algae and diatoms.
Explanation:
Answer:
Spermatogenesis , Spermatogonia
Explanation:
Gonads are the primary sex organs in the male which are the two testes.
Each testis divide into testicular lobules each containing the sparse connective tissue with the endocrine interstitial cells that secrets testosterone, and also contains one to four highly convoluted seminiferous tubules which is responsible for sperm production.
The process is known as <u>spermatogenesis</u>.
This process begins with mitotic division of stem cells which are located close to basement membrane of tubules. The cells are known as <u>spermatogonial stem cell</u>s. The division produces two types of cells.
Type A cells are the cells which replenish stem cells and type B cells are the cells which differentiate into spermatocytes. They have number of chromosomes = 46.